The Paleozoic group. The geology of ten counties of northwestern Georgia

FRONTISPIECE.

PLATE J.

DEATON (COUPER) IRON ORE PITS, Polk County, into which lime tone "horses" rise.

GEOLOGICAL SURVEY OF GEORGIA ..
THE PA.LEOZOIC GROUP:
The Geology of Ten Counties of Northwestern Georgia
BY
J. w. SPENCER, A.M., PH. D., F. G. s. (L. AND A. ),
STATE GEOLOQISl'. PUBLISHED BY AUTHORITY.
ATLANTA, GA.:
GEO. W. HARRISON,
State Printer. 1893.

ADVISORY BOARD OF THE GEOLOGICAL SURVEY.

(EX Ol''FICIO.)

His ExcELLENCY, W. J. NonTHEN, GovERNOR oF GEORGIA,
PRESIDENT OF BOARD.

RoN. RoBERT T. NESBITT_

_ Commissioner of Agricultute.

RoN. S.D. BRADWELL. --_

_ . . Commissioner of Schools.

RoN. RoBERT U. HAnDE:tiiA:S _ . ___ _ _. __. _.. _~ _- . _Treasurer.

RoN. Wl\L A. WRIGH'r ___ ~ _ . . . . . - - -. Comptroller General .

RoN. J. M. TERRELL - __ _________ _. __ __ . _ Attorney General.

n

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HIS EXCELLENCY, W. J. NoRTHEK,

GovERNOR O.F GEORGIA:

DEAR SIR-I have the honor of transmitti11g to you herewith

my report upon the Paleozoic Group, which constitutes one of the

\ natural great belts of geological formations in Georgia. In this report I have treated Northwestern Georgia from the scientific,

economic and agricultural standpoints.

Yours respectfully,

Atlanta, March 22d, 1893.

J. "' SPENCER, State Geologist.

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GENERAL CONTENTS
OF 'l'HE
REPORT UPON THE PALEOZOIC GROUP OF GEORGIA

I. GEOLOGICAL AND PHYSICAL CHARACTERISTICS ..

II. EcoNoMIC GEOLOGY.

III. THE SOILS.

IV.
v.

AcKNOWLEDGMENTs AND PROGREss oF SuRVEY_ SPECIAL CONfl'ENTS OF CHAP'l'EBS.

VI. INDEX.

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PART I.
GEOLOGICAL AND PHYSICAL CHARACTERISTICS
OF THE
PALEOZOIC GROUP
OF
GEORGIA,
IN YOLK, FLOYD, BARTOW, GORDON, :MURRAY, WH1TFIELD,
CATOOSA, CHA'fTOOGA, WALKER AND DADE COUNTIES.
}IY
J. W. SPENCER.
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Geology of the Paleozoic Group.
CHAPTER I.
S KETCH OF THE GENERAL GEOLOGICAL STRUCTURE OF NORTHWEST GEORGIA.
CONTENTS.
NoTE. LITHOLOGY: Igneous Ro'"ks, Sedimentary Rocks, Limestones, Metamorphic
Rocks. ll'oRMA'l'ION AND DEs'l'RUC'l'ION OF RocKs: Cause of Rock Decay, ]'ormatio~ of
New Beds of Rocks. EFFECTS QF TERRES'l'RIAI~ l'rloVEMEN'fS ON GROWTH 0~' Sl'RA'l'A : Oscillation,
Unconfmmity, Succession of like and unlike Materials, Fossils, Position of Strata. GREAT GEOLOGICAL BELTS OF GEORGIA. INCOMPLE'l'EN.ESS OF THE GEOLOGICAl. FoR~fA'l'IONS AND MoDE OF REGIONAL GROWTH. DISTURBANCES AND DrsLOCA'l'IONS OF THE ORIGINAL BEDS: Elevation ancl Folding of Beds, Faults, Effects of Folding upon the Materials of th!l Bed~, Effects of Atmosphel'ic Action upon the Folds. DEcAY oF SurER~'ICIAL l'l.ocKs IN NoRTHWEST GEORGIA. ORIGIN OF VALLEYS. l1ECEN'l' GRAVELS AND LoA~Is.
NOTE .
.Note.-The topographic features, the soils, and the resources of the State are all the outgrowth of the geological structure. The facilities for geological investigations are dependent upon the physical features of the country. Owing to this reciprocal relationship of topography and structure, an intelligent view of the geology of a limited region requires a general survey of the whole. The foundation rocks, which are exposed in any locality, are only some of the many series which go to make up the state or even continent; so that
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GEOLOGY OF 'l'HE PALEOZOIC GROUP.
"'ome knowledge of the general geological laws and classification becomes necessary for understanding the problems presented in these :investigations.
The object of the geological survey is principally for the bene-
nt of the citizens of Georgia; and particularly those who are not
familiar with geological . science, rather than for the specialist. As the present report co\-ers a territory which comes in contact with rocks not yet scientifically studied, but with striking boundaries, owing, in part, to great dislocations and repetitions of strata, it is advisable to give some general explanations of geological structures as related to the country in question. without constant attention to the general characteristics described, it would be impossibfe to get any order out of the complex structu~e of the State. vVhilst over the vastly greater area of the continent, only rocks of ,-;edimentary or organic origin are found, here in Georgia igneous :and metamorphic rocks occupy a large area of the State.
LITHOLOGY.
I,gneol8 Rocks.-The igneous rocks have resulted from fusion processes, and belong, on some portion of the globe or another, to all geological periods. But as the globe .has passed through various stages of consolidation from the gaseous condition, it appears that the oldest rocks of the earth's crust are igneous, and from them all the forms have ultimately been derived. Of younger igneous rocks none are found in Georgia; and of the older, granite may be taken as a type; but igneous rocks do not occur in the belt :-:nrveved.
Sedimentcwy Rocks.- Whilst tbe sedimentary formations have been primarily derived from older igneous rocks, the newer have often resulted from the destruction of older stratified rocks; tbe most common forms of these materials are gravel, sandstones, shaleil or hardened clays, ancl limestones.
Lime.~tone.~.-Limestones are of sedimentary origin, but mostly

LITHOLOGY .
:accumulated through the agencies of marine animal life, from cal-careous matters dissolved in the waters.
Metamorphic Rocks are commonly sedimentary deposits (ot occasionally igneous rocks), rendered crystalline and compact through agency of heat, in presence of moisture, acting upon unaltered rocks. There are various degrees of rock metamorphism. The metamorphic forma hom; of Georgia a1e of very wide extent. They are also represented in different geological epochs, but the altered rocks, in the State, have tnt yet been scientifically investigated. To these group~> belong such rocks as gneiss, mica schist, hydromica schist, etc. 'The eastern or southeastern edge of the country, now reported upon, is bordered by crystalline strata, which will be referred to in this report by their structure, and not by their scientific relation.ships, as such characteristics are easily distinguishable, even to the most casual observet, especially as the topographic features are also marked.
l'ORMA.TION AND DE'Jl'Rl'CTION OF ROCKS OCC:L'R IN CYCLES.
AR has been stated, the sedimentary rocks are derived from the -older crystalline formations; and these newer strata may again be :altered into crystalline rocks.
Cau8e of Boek Destnwtion.-The great destructive agents in \Vearing down the olrler rocks are the rains, rills, rivers and, along .coast lines, waye actioiL The chemical action of rain water washes .out alkalies, lime, etc., from the crystalline and calcareous rocks, thus leaving them porous and easily washed a\va~' by the rains, rills and rivers.
Every observer in middle Georgia is familiar with the decayed rocks. It was notal ways tb us-once the rocks were as compact as tlw hardest granite. On the northern part of the co_ntinent, the compact rock~ are seen. Their upper layers arc not decayed, but are uudecomposed and hard, becau:;e, in recent times, a geological broom swept from those region~; such decayed rocks and soils as

10

GEOLOGY OF' THE PALEOZOIC OROtJl' .

now cover middle Georgia, lea.-ing, great, barren, desolate regions. But from our southern uplands, the rills anrl rivers are carrying off the remains of decaying rock, almost as fast as they fonn. The degree and amount of the rock decay varies, ranging from theincipient decay of some superficial granites, to depths of 95 feet near Atlanta. In northwestern Georgia, the decayed remains of limestones reach a thickness of 200 feet, whilst" the maximum depth ,of residual earth is not known. In this case, the calcareous matter is dissolved away, leaving a great accumulation of residual siliceous impurities, covering the irregularly weathered surfaces of the limestones (as in figure 1, see also plate III.)

Jr. .

FwuRE 1.-At lime quarry two miles east of Kingston-Hesidual clays coveringthe unequally weathered aurfaces of limestone.
The Forrnations of New Beds of Rock8.-The washi1ig~"" uf tlll' land are carried down to the sea; some portions, f.luch afi soluble alkalies, lime, etc., are borne off in solution. The muds are carried off to be assorted and laid down beneath the sea as the foundation of new lands; the sand and pebbles formv shore depo;;its and th(~ fine clays and muds cover the more distant sea bottoms, in near!: horizontal sheets. . For the conditions of the deposition of iron, manganese, alumina, see the Economic Report.

'l'ERRI~S'l'IUAL :'.IOYE~U~NTS.

11

Thus the destruction of the land by atmospheric agents onl~' :;upplies materials for the constructiou of new lands by the sea.
Upon the mud and clay plains, formed on the neighboring sea bottom, marine organisms, as shells, corals, etc., grow and extract from the sea water dissolved calcareous matter; and from their remains the accumulating muds or sands become calcateow;, or are succeeded by beds of limestones of varying rlegrees of purity and thickness.

El'Fl!:CT OF TERRESTRIAL MOVEMENTa ON GHOWTH OF STRATA.
Oscillation.s.-The greater portion of the land wastes are accumulated neat the shore, with the beds becoming thinner, 011 extending sea wards-the sea bottoms remaining nearly stationary. The margins may be characterized hy swamps or lagoons, which are being gradually filled by the detritus brought down by the ri VeL'S or carried along by thP coastal currents. These deposits grow outward and haYe only the thickness of the depth of the sea. But the sandstones, shales and limestones have often a development of thousands of feet, and also alternatP. with each other. This great thickness results from accumulations of the various muds upon a sinking sea bottom. In some portionR of mountainous regions, this subsiding of the land has permitted of accumulations of rock to a thickneRI:\ of many mileR upon the original sea floor, although in 110 place is the sea nearly so deep, but the floor has yielded to the great weight of the forming beds. This great thickness diminishes to a mile or less in the interior of the continent. The subsiding is not continuous, and in many regions, it is replaC'ed by moYements of elevation. The amount of uplift ha~ again become sufficient to bting the newly formed beds above the sea level, whereupon, the atmospheric agents begin to grind them down or carve them out into prominent features.
Unconj'o1mity.-Upon imbsequent :mhsidence, these recent lands again become covered with sheets of new sediments, but they do not lie flat upon the underlyi ug disturbed i;urfilCes, and here then is

12

GEOLOG-Y 01" THE l'ALEOZOJC GROUP.

produced a most important structure which geologists call nncon.fonnity. Sometimes unconformity represents only short. intervals of time elapsing betweeu the production of the succeeding strata, or it may indicate long eras-that is to say, long breaks in the geological succession. But the structure is always most important in making geological surveys. Thus, if formations, belonging to horizons above, let. us say the Coal .Measures, are discovered, reating directly above others which belong beneath them, it would indicate the absence of coal and would be useless to search for coal in localities showing such gaps. This enormous unconformity may be represented by weathered surfaces and water channels as shown between d and c in figure 2, or b~ disturbances in position of beds as between b and c, or by both disturbances of beds and surface .erosions as between aa and the other strata.

FmuRE 2. - Showing unconformities.
8-ucces.~iori of Unlike Jlfate'f'ial8.-when the crust movements do not bring the sea bottom abo\e its surface, but only produce vary; ug conditions of depth or uhanges of currents, as from muddy to .dea,r water, or vica versa, alternating beds of sandstones, .~hales or limestones, in varying degrees of purity, may be formed. Under ,-.;uch circumstances different materials may all belong to the same or to different geological hori:wns, extending over wide areas, as the conditions obtaining throughout the geological periods, or their formations, may have varied. vVheu the same conditions extended nver wide regions, the lithological characters of the strata, as now seen, are of primary value in the surveys. But the uniformity <Jf deposits does not generally continue for great periods of time

POSITION OP STRATA.
over extensive areas-thus the sandstones are shore accumulations of the same formations, which are composed of mnds farther ~eaward, or still beyond or aboVf~, of limestones; and the relationship of one class of cleposits may sometimes be traceable, upon litholog-
ical ground alone, into the others. But it is often necessary to resort
to the use of fossils.
Fo8sils.-The animal and vegetable organisms living upon the coast, or in the deeper sea, leave theit more lasting remains embedded in the accumulating muds, which are building future rock format~on. In the lapse of time, the families of animals ~md plants often change so that the inhabitants of one period are replaced by other types in succeeding periods. Their remains preserved in the rocks, then, become chanicteristic records, and upon them we must ultimately depend for the recog~ition of the difl'erent geological horizons. And each of the formation's of geological cla~sification has irs own value, whether positive or negative, to agriculture, mining and manufacture.
Po.~ition of' Strata.-Except the primitive rucks of the globe, of which we haYe perhaps no knowledge, and also such igneous rocks as have been forced through or into stratified masses, the accumulations of all the geological formations have been more or less in horizontal beds, beneath the surface of water. Had they abo remained in this horizontal position, the earth's surface would have been less marked by the wrinkles and scars of mountain range~', and our knowledge would have been more superficial and less Yaried. There are \:ery few strata that do not dip gently, even a few feet pet mile, in some directions. In such cases, as in southern Georgia, the :,;ame formations occupy broad belt~;. Ii1 middle and northern Georgia, the rocks seldom lie flat, and they are often thrown at high anglef', or even turned upon theit edges. But upon receding towar(h; the interior of the continent, the strata are flattened out again, and abo become thinner.

14

GEOLOGY OF THE PALEOZOIC GROUP.

THE GREAT GEOLOGICAL BELTS OF t<EOlWIA.
From such disturbances and reconstruction~, the belts of rock formations in Georgia have arisen. Middle Georgia (as in figure 3) is composed of our most ancient and very old crystalline rocks.

---- --,_,)
FIGURE 3.-A, Arcluenn backbone of theStnte; B, Paleo:r.oic gtoup; ~I, Mesozoic; C, Cenozoic.
The Arch!an (and most other) strata are resting at all angles, but generally dip to the east-southeast. If we take a line aetoss the State from northwest to southeast, that portion between Cartersville and Macon is composed of metamorphic strata. To the northwest of this first point the rocks are all indurated, and belong to the Paleozoic (means ancient life) formations, which may lie almost horizontal, or again may be almost vertical, and at all angles between; bnt the prevailing dip is usually moderate, and of less than
:wo in direction east-soritheast\yard. Still, in many places, espe-
cially, in going continentward, the clip is in the opposite direction. The lower beds are oft<:'n abnormal!~' brought into higher positionro by faulting.
Southeast of Maeon the Btrata have an entirely different aspect, dipping only a few feet per mile to the southeast. Exclusive of

REGIONAL GROWTH.

15

some of the limestones, most of the strata are poorly consolidated rocks, everywhere having a youthful appearance, and belong to a limited degree to the upper Mesozoic (middle life), but mo.">tly to the Cenozoic (new life) group.
Thus it appears that in most ancient times Georgia was a portion of a great island, commencing in Alabama, broadening in Georgia, even far coaRtward of prer;ent surface exposures, of crystalline formations, and extending towards the northeast. On tbe one side there are very old and disturbed strata; on the other side the fo1mations are comparatively young.
I~C01IPLETENESS OF THE GEOLOGICAL FORMATIONS AND MODE OF REGIONAL GROWTH.
The physical revolutions of the early geological times left the formations west ofGeorgia above the sea line, for there is a general absence of the succeeding formations toward the southeast. Yet these may have once been local!:; deposited, and since washed away by the enormous denudation whieh occurred. But except the western portion of the metamorphic zone, Georgia formed part of an islaml in the earlie1; geological periods. The eastern side of the ancient land extended far eastwat'd of the present surface limit of metamorphic belt, even perhaps far seaward, as the continental margin, now submerged, extends 200 miles oceanward of the coast of Georgia. Central and northwestern Georgia long remained abo\'e the tirle, during the time that the Paleor.nie formations were aecnmnlati ng upon its western side. Indeed, the southeasterit lands <late back only to a period subsequent to the uplift ani! formation of the mountain ridges of northwestern Georgia. But it is with nort.hwesteru Georgia we are here mostly concerned.
Prom the early Paleozoic era, the Georgia lands weJ'e bordered npon their northwestern side by a ~ea, into which the washings of the land were being carried. These washings now form various hardened sedimentary rocks, intercalated with beds of limestone, originally of great thickness. These accumulations were laid down

16

GEOLOGY OF THE PALEOZOIC C+ROUP.

more or less horizontally along the old seashore. Throughout thePaleozoic era, there was not simply a continuous submergence beneath the sea, but there were periods when much of that part of the State became dry land, only to be again submerged. Thus the Paleozoic series are incomplete. Bnt eventually the sea was filled up, leaving swamps in the northwest corner of the State, in which coal-making vegetable accumulations were forming. Throughout this succession of events the general horizontality of the beds was not greatly disturbed. No mountains existed, and no other valleys than those which the drainage of the generally level lands of the <lifferent periods had produced. All the mountain features were only ('Ompleted at or since the close of the Paleozoic era. Even the deformations of the then more or less rugged features of centra I Georgia have had their strata still further disturbed at the time of the uplift of the mountains of the northwestern parts of the State.

DISTURBANCES AND DISLOCATIONS 01' THE ORIGINAL BEDS.
Ele11atiun and Folclin,q of the Beds.-By the elevation uf the mountains at the close of the Paleozoic era, the general trend of the ridges from northeastward to Houthwestward, and the outcrops of the various formations in that direction, have brought to view belts of variable widths. This uplift was a complex movement of a portion of the earth's cruRt, acting from the southeastward, and diminishing in the extreme northwestern corner of the State, as the strata flattens out toward the interior of the continent. The stmta in the moutainous region of northwest Georgia have not been merely thrown into all degrees of inclination, hut have also been folded into ridges (the term anticlincd being applied to strata dipping from the axis of the folds) and troughs (.synclinal.~ where the strata dipped towards the hollow) or forced one set of beds upon the other,; (faults). These mov~ments occur upon the gigantic scale ai'i well as in miniature, from which the study of the greater movements

FOLDING OF STRATA.

17

can be made. Also by laboratory experiments, many of the terres trial movements may be immitated.
An example, of the more simple folding, is shown in figure 4, from a photograph taken along the Ocoee river, wherein th<> squeezing passes, in places, into fracture, producing a con vex structure

FIGURE 4.-Bending and fracture of strata along the Ocoee river; a a a represent quartzose beds; b b b, are slates.
which eventually overturns some of the strata. In the movement,. the slaty beds (shaded portions of figure) have more or less adjusted themselves by being squeezed into position, but' the quartzose layers are those which have been bent and broken.
The folded structure is carried farther and is well shown along a section near the iron bridge over the Etowah river, southeast of Cartersville (figure 5). The section has a length of about 400 feet. Here two synclinals and three anticlinals occur, in which the beds upon the northwestern side dip the more steeply and are somewhat overthrown. Erosion has denuded the crests, and if the surface of the section were lev~!, only a number of strata dipping in different directions would be visible; but these would be sufficient for recog-

18

GEOLOGY OF '.rHE PALEOZOIC GROUP.

nizing the position of the beds. However, washes in the road havP. give n more perfect exposures, and thus a fine study may be seen.

FIGURE 5.-SAction at Iron bridge, south of Cartersville; n n a represent unti_ clinal folds; s s, synclinal folds.
T he undulation on a grand scale may be SE en in figure 6.

Scale

3 Mile.s

1/i>rkcal

10 9rt>et

FIGURE 6.-Sections across Sand, Lookout and Pigeon n1ountnins, showing

undulations of strata.

When the thrusts are continued after p,assing the limit of folding, the strata mnst be faulted (as at F, figure 7). A beautiful example on a Rmall scale, in a section ahout 200 feet long, is seen at the cut of the Western and Atlantic Railway, on the northwestern bank of the Etowah river.

Fwu RE 7.-F represents fault line, c, decayed r ock .
Here, th en, is an anticlinal with axis trending northeastward, the thrust coming from the southeast. The upper beds, along the fault line are completely cut in two and slidden over those

FAULTS.

19

upon one side of the fault. Lower down in the section, the fracture and slip has been less perfect, with the beds forced into an anticlinal and carried to the point of fracture, with only a slight slipping and a tendency to invert the strata. By the position of the layers other complex movements are indicated, but not exposed in the cut.
On the large scale, we find all the above conditions tepeated, and great beds are often inverted. These complex features add to the difficulty of determining the thickness of formations, and location of special layers, when the lithological characteristics and the fossil contents do not readily explain the conditions.
Faults.-Tbe further thrusts not only produce breaks, but often carry the beds over upon other strata,. In some casee, these slip~;, technically called faults, will simply lift the rocks upon one side of the break or produce a downthro'w, so that the same beds are no longer continuous (F, figure 7).
Very often, when the strata are pushed over the others, the movement becomes a thntst fault, in which case the beds upon the side of the fracture, from which the movement com8s, are forced over those upon the opposite side, or, in northwestern Georgia~ those on the southeastern ;;ide slide over towards the north west. This is a nmmal thrustjmtlt. An illustration of thrust faults is seen west of

FrouRr; B.-Illustrating a thrust fault (adapted Irom Hayes). F F F F, line of fautt; Ca, Cambrian shales forced over Silurian (R ) nncl Sub-Carboniferous (Cf) strata.
Rome, where a narrow trough of Cambrian strata has been carried at least four miles to the westward, over Sub-Carboniferous strata, as shown in figure 8. Tbi~ thrust fault represents a vertical dislocation of from 7,000 to 10,000 feet. Erosion has caused the remoYal of the shales between the trough and the Cambrian belt to the east-

20

GEOLOGY OF THE PALEOZOIC GROUP.

ward over what is now known as Horseleg mountain, which wasforced up during or aftet tbefaulting movement. This will be again desetibed in the local geology.
Thus, although the. whole series of beds may dip to the southeast, yet the newer are those towards the northwest, and appear to underlie the others, which would be the case if the faults did uot exist.
Such faults are common ou large scales in northwestern Georgia, bringing into contact widely separated geological horizons. StiII more frequently the same series of beds are repeated in parallel ridges; also small faults are very common, repeating the same adjacent strata; and others which do not amount to more than a few feet. Often the structure is very complex, atising ftom a combination of folds and faultfl, as shown in faults at Cave Spring and at Erwin.

FIGURE 9 -Faults F F F F, one mile we't of Cave Spring. Strata Cl'U8bed at a, nnd decu)ed at e f rl and h.
It is by one of these great thrust faults that the metamOI'ph ie rocks are brought into contact, and indeed overlie the Paleozoic rocks all the way along the southeastern margin of the belt und~r exploration. This overthrust of the crystalline rocks above Cambrian limefltone is well shown along the creek at Erwin's Milh; on the southern border of Gordon county.
Sometim<.Js the troughs of the folds are thrust under their arches, when the effect is the converi;e of the above, as if the movement came from the opposite direction; such are called revused thnu:; ]mdts.
In normal faulting, the overlying strata are much nearer the horizontal than the more steeply inclined and overridden beds,

EFFECTS OF FOLDING UPON STRATA.

21

these last occurring on the northwestern side of the folds. The {)pposite is true in reversed faults.
In normal faulting, the lower beds are sometimes dragged over, ptoducing subordinate and local reversed folds.
The effects pf the faulting and repetition of the same beds have not been merely to make simple ridges and valleys. These folds and faults are coincident with both the great and small valleys crossing not only the State, but extending from Alabama across Georgia to :fennessee and northward. In the northwestern part of the belt reported on, the same strata are brought to view in narrow belts rising from beneath upper Paleozoic strata, which are wanting to the east. Accordingly, the same sheets of lower Paleozoic beds, Once nearly horizontal, still occur everywhere beneath all the various series of the overlying series.
E;tl'ect8 of Folding ttpon the JYiateria.ls of the Strata. are primarily to hmdeu them, and often to produce metamorphism of various degrees. Thus, the original textures become more or lrss obliterated, .as also the organic remains; and then the fossils are rare or very obscure. Such rocks are apt to be more or less traversed by veins. Y ery often the internal slipping in the rocks results in polished joints or surfaces (which structure is called slickenside). Tbejoints'are not a! ways visible, but form lines of easy fracture or decay.
Ef/'<Cct8 of Atmospheric Action upon the Folds.--The crests of the f(llds, especially where the thrusts have produced faults, are more Ol' less ti:actnred and weak; whilst the troughs have the matetial of the beds hardened. Accordingly, the ridges are not only more I'X posed to the action of rains, washes and rills, but more susceptible ttl destruction on account of the accessibility of these w~athering ngents to the materials and their weakened powers of resistance. Con.,~equently the rock structures of the valleys are commonly anticlinal, nr the remaining ledge of the rocks dip from the axis of the valleys :into the sides of the ridges. But the destruction of these ridges, goj ng on more rapidly in the steep beds, as on the side removed from

22

GEOLOGY OF '!'HE PALEOZOIC (fROUPR.

the directon of thrust, than in the more gently inclining strata of the other side, may remove all surface traces of the anticlinal structure, so that the country is composed of series of ridges and valleys, with the strata all dipping, but at varying angles, in the same direction as if they were monoclinal, whilst in reality the valleys are often anticlinal. This condition adds to the number of ridges and repetitions of strata in northwestern Georgia, being often the re~mlt of folding rather than faulting, and accounts very often for the small number of places where the rocks seem to dip northwestward.
Many of the narrow ridges, separated by valleys, are characterized by disturbed strata, in which the more durable beds, such as cherty layers, have been elevated and occur in parallel belts, with the more calcareous layers. In this case, unequal decay has been the immediate cause of the ridges, protected often by only thin chert covenngs, whilst the rains and washes affected the .valley!'. Such valleys, although occupied by streams, do not usually indicate their excavation by great rivers.

DECAY OF THE SUPERFICIAL ROCKS OB' NORTHWESTERN GEORGIA.
Everywhere the surface rocks are deeply decayed, and the surface soils have been formed without extensive transportation, except adjacent to the streams. Some of the limestones have been impure from admixtures of clay, and of cherty masses. From these, the calcareous matter has been extensively removed, and in many places, the surfaces are covered with a mantle of clay and cherty gravel. So great has been the destruction of the limestones, that in their place may be found from 100 to 210 feet, and perhaps even more, of residual clay, as in the valley at Oredell (in Polk county), or near Tunnel Hill. Owing to this great accumulation of surface debris the complicated structure is obscured, 'so that the only surface indication of the faults is the sudden transition from one kind of soil to another. However, there is method in the distribution of this mantle of loose earth, so that from the survey

REMOVAL OP LDIERTONES.

23

of the soils, etc., the distribution of the different geological forma~ tions can be recognized, and upon the distribution of the forma-
tions the valu~ of the land depends.

FIGURE 10.-Decay of dolomitic limestones (a be dJ upon the surface an<i side of ridge near Cave Springs. c, represents the more siliceous beds; L, the more calcareous; M, manganese boulders.
Residual earths, derived from decayed limestones may be seen from analyses in the agricultural report to contain from 64 to 84 per cent. of silica; from 6 to 15 per cent. of alumina, and from 3 to 10 per cent. of ferric oxide. Such rocks as those from which the decayed remains were derived, contained, only from :3.5 to 6 per cent. of silica; from 1 to 3 per cent. of alumina, and from half of 1 to 2 per cent. of ferric oxide. Occasionally, in very impure Hmestone the proportion of alumina and ferruginous matter is vastly increased. In the decay, more or less iron is dissolved out, and the clay washed out. But most of the silica remains in the residual earth. From a careful study of analyses of soils, derived from Knox dolomite rocks, there is found to remain about 67 per cent. of silica. If the standard of 6 per cent.. of silica be that taken in the original limestone, it appears that ten times aB much calcareous matter has been removed as there are residual earths remaining. Reducing this somewhat, and allowing for local variations, it is safe to assume that every foot of snch debris was once represented by ten feet of more or less impure lime rocks. Thus, in places, as much as 2,000 feet of limestone appear to have been removed by the solution of the original calcareous rocks of

24

GEOLOGY OF 'l'HE PALEOZOIC GROUP.

northwestern Georgia, leaving a mixture of elements of nearly the 8ame composition as those derived from calcareous shales.

ORIGI~ OF THE VALLEYS.

This question is a natural sequence to the consideration of the

last two paragraphs. Although the Paleozoic belt of northwest

Georgia is characterized by both broad and narrow valleys, some-

times separated by narrow ridges, or again by sharp crested, or by

broad mountains, yet this configuration is immediately due to the effects of meteoric and river erosion; that is to say, that the present

valleys would not exist where they occm if the materialR which

(Jnce filled them had not been carried oft' by washes and streams.

'I

This is true even though the location of the streams may have

been primarily determined by movements of the earth's crnF>t,

which has produced warping and ridges of upturned beds of rock.

However, such movements haYe been slower than the carving of

the valleys out of the more easily degraded rock beds.

In the old Coosa basin, the origin of the valleys may not appear so simple as those of the newer formations of the Chickamauga

and Lookout valleys, from the stmcture of which the key to the ex.

planation of the older valleys to the east is obtained.

Let the Lookout yaJley be taken as an example. That valley is bounded on either side by plateaus from a few bund~ed to as

much as fifteen hundred feet above the floor. The plateaus, which

were formerly one plain, is capped by hard durable sandstones, lying

at low angles, dipping from the valley on both sides. This plateau

has been incised by Lookout creek and its branches, until the

stream reached the base level of erosion, deeper than which the

valleys could not be cut. The streams then began to btoaden th0

valley, which is now two. to four miles in width. This widening

could not have been done by Lookout creek alone, but by the tributary streams, rills and rains undermining the mountain side~.

Upon Lookout mountain, there are still many streams cutting down

to the base level of erosion, and the various stages of valley making

ORIGIN OF VALLEYS.

25

are in progress. where the streams are flowing in opposite directions, there the heads of the valleys gradually unite and often appear as one continuous valley, with walls hundreds of feet high . and miles in width, as may be seen at the union of Lookout and Big wills' creek valleys.

Fw u m: 11 .-Map showing form o f the brond, deep vnl)ey, cut into the forme rly nne plateau of Lovkout- Sand mountain table-lnnd, nt the heads of Lookout and vVills' creeks.
FrcwaE 12.-Section across Lookout valley, near Sulphur Springs, showing Cllm bined erosive effects of small streams in making a broad valley.
The Yalleys just described were once filled with the Carboniferous rocb> containing valuable beds of coal, which have been swept :away and carried into the sea. From narrow ravines this proces:,; nf degradation of the rocks may be traced through various developments to twenty miles or more in width. Here and there remnants of degraded formations are left, showing that even the Caeboniferous rocks extended much further into Georgia than the valHable beds of to-day; thus it becomes apparent that 1,500 feet of

26:

GEOLOGY. 01!' THE PALEOZOIC OROUP.

Carboniferous rocks alone, and elsewhere 2,.000 feet or more or limestones, belonging to the earlier Paleozoic periods3 have been removed from what a,re now t.he valleys of northwest Georgia.
RECENT GRAVELS AND LOAMS.
Often coarse quartz gravel and other stones, as well as asRociated lmims, are foun(l in the valleys up to elevations,from 80 feet to 150> feet. The>~e are not everywhere met with, but are very common;. and represent bar or other shore deposits in the great, broad streams, at a late period, wheu the lower parts of Geurgia weresubmerged to a depth of 700 or 800 feet. Locally the soils arethus made to vary from that of the residual clays.

GEOLOGICAL GROUPS.

27

CHAPTER II.

GEOLOGICAL GROUPS OF NORTHWEST GEORGIA.

CONTENTS.
TABLE OF GEOLOGICAL GROUPS. GNOLOGICAL SYSTEMS O.F NoRTHWES1'ERN GEORGIA-Eustern Border Rnnge of
Unaltered Formations. PALEOZOIC FoRMATIONS OF GEORGIA-Table, Value of Fossils. THICKSESS OF THE LOWER PALEOZOIC FoRMATIONS; OF THE UPPER PAL~;ozou
ROCK!>. J.<'AULTS.
TABLE.OF GEOLOGICAL GRO UPS.
In order to give a clear idea of the order of superposition of the different formations which geologists recognize, and the relations of the strata occurring in Georgia, the following table is given:

GROUPS,

SYSTEMS.

LOCATION JN GEORGIA.

I ~1od ern ..... . .. .'. .

Ri ver deposits.

il1 Pleistocene . . . . . . . .

(South Georgia.)

CENOZOIC. , !:l.iocene . . . .. . } Neocene { southh GGeorg!R.

~uJOcen e . . .. , , .

8 out eurgJR.

Eocene , . . . . . . . .

South Georgia

Cretaceou~< . ...... .

MESOZOIC.

.

{

Jurassic.. Triassic .

.

.

. . , .. ....

. .

South Georgia. Not known. Not known.

!' Permian .... , Carbonifsrou!' . , Devonian . . l'ALEOZOIC Silurian . . . ...
lOrdovician . . , . , Cambrian . . ... .
ARCH~ AN . {Metamorphic Roeks

Not known. "N ottillwe ~ :GeorgiA .
1'w'ijL G>l. , bu~ 11 lm ostw ' ntitw. Nor th west Geur!!;ln. [on l v o11 e
amnll b ut illlporiant fr!w rncm t )N o:vthwest (:;l:eol!;il!. N onc h w os~ eo rgin.
(Laurentian and . other ~ys tems(? ). These have not bee n differentiated in Middle Gn.

GEOLOGICAL SYSTEMS IN NORTHWESTERN GEORGIA.
Easte1n border of tma.lte?ed 1ocks are all more or less metamorphic or igneous. The upper beds. belong to systems distinct from
(2i)

:28

GEOLOGY OF THE PALEOZOIC GROUP.

the lower, just as the Paleozoic group is comprised of several systems. In several scattered regions in America, there are well marked series of crystalline accumulations d,evoid of determin-able fossils, which overlie the lower Archooan, and underlie some member or other of the Paleozoic group, but they cannot be eorrelated as yet or positiYely assigned to a 'lystem in the general table. In such cases, we must simply investigate the local characteristics and wait until their true relationships have been discovered. Such rocks form important members of the metamorphic country east of the belt. under survey, against which it is brought by a gigantic fault, which has been suitably narned the
* "' Cartersville Fault," uy Dr. C. vY. Hayes.
It is quite probable that some of thes~ upper crystalline rocks belong to the Cambrian system; but as they occur east of the physiCal break, they will not be considered here.
Range of Geologico! Fwmations.-Throughout the belt repotted upon, the rocks range front the Cambr.ian to the Carboniferous system, inclusiYe. But the lower beds of the Cambrian system, and possibly portions of' the upper Ordovician formations, are wantigg....._,, In the northwestern portion of the area surveyed, there are most .'ltriking repetitions of the formations. The northwestern side of the Lower Paleozoic strata of the Coosa valley are brought in contact with the various upper members of the Paleozoic group; but particularly with the rocks of the Carboniferous system. This fi:wlt has been explored from Yirginia to Alabama, and was first uamed [by Prof. J. J. Stevenson,i- the "Saltville Fault," since locally called the "Rome Fault," by Dr. Hayes.t Iu Georgia this fault amounts to a Yertical displacement of from 7,000-10,000 feet.
<:>Bull. <'eological Society, Am. Yoltfme Ij:. 1890. P>lge 147. t ,1, J. Stevenson, Pro. Am. Phil. Soc. XXII. Phila, 18R4. :j: Bull. Geological Society, Am: Volume II. Page 144.

PALEOZOIC FORMATIONS OF GEORGIA.

SYSTEM. CARBONIFEROUS

Serie~.
Coal Measures.

NAmes of Formations in Safford's Equivalents in

Georgift.

Tenn .

Coal Melli'ures.

Coal Measures.

Smith's Equivalents in Alt<.
Coal Measures.

Hayes' Equivalents.
{Walden Sandstone.
Lookout Sandstone.

- Lower .orSubCarbon iferous.

Mountain Limestone. :Floyd Shales.
Fort Payne Chert.

Mountain Limestone.

Bangor Limestone.

Bangor Limestone.

Siliceous Group.

{ Oxmore Sandstone and "Shal(S.
Fort Payne Chert.

Floyd Shales. Fort Payne Chert.

DEVONIAN.

Chattanooga Black Shales.

Black Shale.

Black Shale.

Cliattanooga Black Shales.

SILURIAN. ORDOVI<.;IAN.

Clinton. (?)
Hudson. Trenton. Chazy. Calciferous.

Red Mountain.

Dyestone, gr. White Oak Mt. and Clinch Mt. Sandstone.

Chickamauga tll)elllding Rockmart Slate). ' Knox Dolomite.

Nashville. Trenton. Maclurea. Knox Dolomite.

Red Mountain.
Trenton or Pelham Limestone.
Knox Dolomite.

Rockwood.
.
Chickamauga Limestone.
Knox Dolomite.

\!:BRIAN.

Potsdam. (Up. Com)

Acadian. (Mid. Cam.)
Georgia. (Lower Cam.)
- - -- --- ---

Oostanaulo. Shales.

Kuox Shales. Knox Sandstone.

{Montevallo ShRles in

eluding Weisner quartzite

{ Conneso.uga Shales. Rome Sandstone.

Coo'a Shales.

Chilhowie Snunstone.

--

Ocoee Conglomerate.

- ..- - . _ -- - ~- -: --,:<-- - - --:--::-- -;:-_ .-:.::-.-. - - - - - -----~- - - -, - - . - . - - - - : _ ... ~-----,....- _--=:--

-

:30

GEOLOGY OF THE PALEOZOIC GROUP.

Value of Fossils.-The gt'Ouping3 of geological phenomena

scarcely reached the dignity of a science until William Smith, an

English mineral surveyor, discovered that certain fossils were char-

acteristic of special ):>eds, and were not found out of their proper

hotizons. He made use of his discovery a century ago, in order to

ascertain whether the rocks were above or below the coal horizon.

Lithological characters of themselves are only, at best, local indica-

tions of age, or of horizon; for rocks of the same position over widely

separated areas may be of 'entirely different characters, or rocks tf

the ame characters may belong to differebt horizons; consequently

geologists must ultimately depend upon the fossil contents of differ-

ent beds. Again, many physical breaks occm in the succession of

i'ltmta, and characterize certain epochs in one locality, without leav..

ing traces iu ot.hers. They are not always coincident with the great

ehauges in the types of fossil remains. Thus, there is a closer. re-

lationship between the .~edimentation of the Knox shales and the

Knox dolomites than between the Knox dolomites and the overly-

ing Chickamauga fotmation, although both of these latter are highly

calcareous deposits; yet the relationship of the animal remains is

such as to cause the Knox shales and Knox dolomites to he placed

in different systems. In.deecl, it is only on account of the inability

to pel'fectly correlate the minot gtouping ovet widely separated

areas that local nomenclature lasts longer than a temporary pro-

. vtston. This
of formations,

inability arises from various thinning onL or thickening

bteaks in of strata,

tahned cionntthi neurieh"-

placement of one kind of deposits by another, with the consequent

changes, unequal development and preservations of fossils. As an

illustration : sandy shore deposits are apt to be replaced by clays

found in deeper water; or limestone;,, when the waters were clear

enough to favor accumulations of animaJ life and their consequent

remai nt>. Thus, on the flanks of mountainous countl!ies, sandstones or

shore deposits occur, whilst, us the formations recede towards the

plains of the continent, these fragmental members diminish in mag-

'fHIDKNESS OF STRATA.

31

nitude, and are often replaced by limestones which are more favorable for the preservation of fossils thau the clays and sandstones. Acco.rdingly, by tracing continuity in the stmtigraphy, portions of the beds may be found which are fossiliferous, and thus the horizons can be determined; still, the general types of the whole remain with local variations.
Throughout the southwestern end of the Appalachians, the fossils of the Lower Paleozoic formations are not generally preserved; and on the lithological characters one must often depend in surveying the development of many formation s, "ith only occasional references to fossiliferous strata.

THICKJ\ESS OF THE LOWER PALEOZOIC FOR~IATIONS .
The difficulty of making accurate determinations of the thickness of the various formations is considerable, as the extensive sections of the different rock formations are commonly in decayed conditions, or the strata are buried or obscured. As a consequence, the apperently great thickness may have to he reduced, owing to unperceived undulations or faultings. However, estimates based upon incomplete obsenations are made. Long ago, Prof. Safford* e::;timated the thickness of th e rocks, in E ast Tennessee, which pass into Georgia, as follows:

ORDOVICIAN. CAMBRI AN.

~ashville ai1d }
f Trenton
l Knox Dol mite
( Knox Shales, ~ Knox Sandstone.
l Chilhowie,
? Ocoee,

2,500

feet .

4,000

"

1,.500-2,000 "

800-1,000 "

2,000

"

10,000

Thus the extended thickness of the Cambrian in East Tennessee, without the Ocoee conglomerate, which is not included in the report, is from 4,300-5,000 feet thick; and the Ordovician or Lower Siln-
*Geol. of Tennessee, 18ll9, pp. 158-60.

32

GEOLOGY OF THE PALEOZOIC GROUP.

rian, is 6,500 feet. To the rocks belonging to the Cambrian r:;ystem, Mr. A. R. McCutchen assigned a thickness of 10,400 feet.* In Alabama, Prof. Eugene A. Smith gives the maximum thickness of the Cambrian deposits exclusive of the Ocoee conglomerate, as
10,000 feet; and that of the Ordovician system as 4,900 feet. -r
Dr. C. Willard Hayes estimates the thickner:;s of these same formations in the southern Appalachians at from 6,600 to 8,500 feetj: for the ~\mbt:iau lHid ab v tlt 1 bil b wi and from ! 7 0 to 6 : 00
for the rrloYician syswm.: Th J lt't:'l.-illlllltl thi ku :;, f tb Cam-
bl"ian n +. o'f <rgia at ovc the hil howi uncl Oooe fo.l'mati ou.
mu t rench ~" , )0 o H000 f et ; and th beds of the 01rl< vi cittn must aggregate 6,000 feet in its maximum developments.
THICKNil:SS OF THE UPPER PALEOZOIC FOR~IATIO:-.S.
Most of the Upper Paleozoic formations are more easily measured than those of the lower portions of the group, the maximum thickness of which is shown in the following table:

Carboniferous System. Coal :Vfeasures,

Snb-Carboni ferous,

Devonian

(Tncluaing Floyd shales).
Blaek shales,

Silurian

Red Mountain,

1,400-1,600 feet.. 1,500-2,600 "

10-25

"

800-1,100 "

In northwestern Georgia, the Red Mountain series is developed to a considerable thickness, whilst in Alabama it diminishes to 100 feet. In Tennessee, Safford estimates the whole series at from 1,200 to 1,500 feet., and Mr. Hayes places it at 600 to 1,1'iOO feet.
The Devonian shales dwindle down to 10 feet in Alabama, but

'''See Cotton Report, Tenth Census, Vol. VI., part 2, page 21.
t Geological suney of Alabama, "Cahaba Coal ~'ield," 1890, 148-154. t At the time of Hayes' estimate, he classified the Coosa shales as a number below
the Connesaug11 shales, so also did Smith. BLlt as these local developments appe'u to bolong to the same horizon (Walcott) the larger estimttte has been reduced.
?. "Overthrust Faults of the Southern Appalachians," Bull. Geol. t:loc. Am. 18\JO, page 143.

FAULTS.

33

thicken to 100 feet in Tennessee. The Sub-Carboniferous of Georgia is greatly increased by the Floyd shales, which are locally developed to a thickness that cau be ouly roughly estimated at 2,500 feet (Hayes). Exclusive of these shales, Prof. Safford gives a thickness of the Sub-Carboniferous rock at from 600 to 1,250 feet, and the Coal Measures from 200 to 2,500 feet. In Alabama, Me. Joseph Squires measures a development of 1,200 feet on t.he Sub-Carboniferous, and 5,525 feet for the Coal Measures~ which, however, are much more largely developed iu Alabama than in Geoegia.
FAULTS.
. Many faults oceurs m northwest Georgia where the different formations are duplicated. The most remarkable is the Saltville or Rome fault, which transposes the Cambraiu shales over all formations, even to and including the Carboniferous system. This dislocation is an overthrust fault whereby the Camhrain shales where pushed westward at low angles foe distances of at least four or five miles, bringing into contact formations which are geologically from 7,000 to 10,000 feet apart, in vertical range. This fault is further noticed under the local geology of Floyd and Gordon counties. The great number of repetitions of strata in Whitfield county may
be seen in figure 13.

FIGURE 14.-Section from Rocl<y Face to Cohutta Mountains, showing repetition of Knox strata (1') by faulting (F) nnd folding.

34

GEOLOGY OF ~rHE PALEOZOIC C+ROUP.

CHAPTER III.

GENERAL CHARACTERS OF THE CAMBRIAN SYSTE~I.

CONTENTS.

TABLE.
OcoEE SJmiES.
CHILHO"li'IE SJ<:RIES.
OosTANAULA SERIEs-Coosa Valley Phase; Oostanaula Fault; Connasanga VnL ley Phase.
TABJ.E.

SERIES. FORMATION.

l Upper Cambrian (Potsdam) (

iKnox or Connsauga

.

.

. I Oostanaula

M1ddle Cambnan (Acachan)

Shales. Knox or Rome Sand-

stone.

Lower Cambrian (Georgian) Chilhowie. Oco.ee (?)

THE OCOEE SERIES.
The type of this formation is along the Ocoee riYer, only a short distance from the Georgia line, and these depoeits extend within the State, but their full development is not known. Some of the rocks in eastern Bartow county have been assigned to this horizon by Prof. Little.* With equal propriety, at many points along the western margin of the metamorphic rocks various beds could be assigned to the same series, but the survey has not progressed sufficiently in this di.rection to allow expression of opinion. The rocks along the Ocoee river cover a zone about twelve miles wide, and present a long succession of beds mostly dipping at rather steep
*-Handbook of Georgia, 1876.

OCOEE SERIES.

35

.,angles to the southeast, and forming precipi tons cliffs OYer the river, which cut across the formation. In many places foldings are seen, and elsewhere the Htrat.a is much broken. whilst the faulting and folding is often obscured, it must be very great, or e-lse the thickness of the series would am.ount to five or six miles. Prof. .Safford proyisionally placed the series at 10,000 feet. But it is impossible to make a correct estimate of the thickness. The great proportion of this mass is composed of semi-metamorphic bydromica .schist, cbloritic and clay slates, with occasionally beds of fine con.glomerate and quartzite, which, in some placee, are very thick, especially i.n the higher beds, and to a less extent near the base. The pebbleo are usually small, but sometimes an inch or two long. 'They are composed mm;tly of quartz, with some feldspar, or in places fragments of slate; greenish and bluish slates prevail. They _ate commonly weathered, but in the road making there are many places where the blue compact slates are exposed.
At several points all the way to Cartersville, I have crossed the . edge of the metamorphic zone and found hydro mica schists, slates, .coarse and fine conglomerates, quartzite and sandstone, but as yet have not reported upon them. Yet it is reasonable to expect that .so me of these deposits may be referred here; at any rate, such rocks form the border of the country reported upon.
These rocks have been placed by Prof. Safford in a horizon at -the base of the Cambrian, where we will leave them until future research shall require them to be differently classified. They are not fossiliferous, so far as known, and their strnctural relations are not .easily made out, but. their occurrence is in contact with the known .lower Paleozoic rocks, on account of there is exterisi ve fauliing.
CHILHOWIE SERIHS.
This formation was described by Prof. Safford : "It is a great roup of heavy bedded sandstones, often dark, but generally

36

GEOLOGY OF THE PALEOZOIC GROUP.

weathering to a grayish white, and containing great beds of whitish quartzose sandstone or quartzite. Interstratified with the, many bedded rocks are, at some points, sandy shales and thin flags,. often containing mica scales. Some of the sandstones are coarse
an u ttp poa l fi u cmng lometatc. I t U1 ay be menti n.etl llt<tt J.l t unfi-eq n ntly tL hiLl'il,ta Lav gr en g ains (glrw nitin) di:::-<cminnted
th.r ug h bhem."'t Wom ho.l . (SoolUhn.~ liru:cai.~) tl n1l imp e. : iom; of fu iCI . !l'l' onun ~n .l y fo mul. T he max imum t hi ku 's,; i g ivc n at not less than 2,000 feet. The great topographic feature.3 of the Chilhowie formation is their occurrence in bold, isolated knob~, issuing abruptly out of the valleys to heights of from ] ,000 to 2,000 feet. Such knobs are characteristic features from Alabama to Virginia, but all are probably not of the same age. 0\erlying the sandstones of the typical Chilhowie mountain, Mr. C. D. Walcott found shales containing the Olenelns fauna, thus })roving the col'rect determination of the geological position long ago by Prof. Safford, whereby the formation is shown to belong to the Lower Cambrian series.
In Alabama, l'rof. Eugene A. Smith say~; that the lower part of' the Cambrian system is not characterized by quartzites and sandstones, as by Chilhowie of Tennessee. But that similar masses forming the same bold Chilhowie-like knobs occur at many horizons in the shales.t So also Messrs. 'Villis, Keith and Ha~es haYe obseryed similar extensive range in the geological 'distribution of these sandstones or quartzite knobs at various points in Tennessee. 'l'l t ~l. gt' -'<\L :IC umnl atious of. and were evidcutl lu<:al in poJSit;i n1> close upon the- ttHti.nl :md, w her stre~uns l' ' l\1'1' nt ' we1 pi Iiug tltc washln gs of Lh lnntl . With the Ol:i illnti c 11. in Lit 1 ,. 1 of tlt ' J an~ aut.l ..eu th' lo aHti >s of au h leHo its uaLurall bnng 1, b ing buried by newer sand bars, or having these formed upon the latemuddy sea floors.
.t Geology of Tennessee, 1869, p. 199.
t Geological Survey of Alabama. "Cahaba Coal Field," 1890, p. 150.

OOSTANAULA SERIES.

37

In the country at present reported on, Indian mountain (mostly in Alabama) is the only knob that is considered. Its position is beneath the Oostanaula shales, the basal sandy members of which may be of identical horizon with that of Indian mountain. Some .of the sandstones on Cohutta, Pine Log and other mountains may belong here, a~ suggested by Prof. Little; however, these are on the metamnrphic side of the "Cartersville Fault," which is the limit of the present survey and of this paper, but are :approached in examination of its boundary.
OOSTANAULA SERIES,
COOSA VALLEY PHASE,
This is the lowest formation in which fossils have been found in <Georgia. The mass of the formation is composed of reddish, yellowish, brownish and greenish shales with thin bedded limestones, . having shaly partings, or the limestenes are in concretionary layers within the shale. These beds are often at high angles, and the :great variation of the dip shows much folding and faulting. The .shales weather into stiff soil. Higher in the series there are dark massive limestones: highly seamed by white calcite veins. These rocks cover part of the country known as "fiat woods," along the Coosa valley, and also with some interruptions extend northwestward to near Dalton. In part, is a comparatively level country, :and in part it is composed of moderate sized ridges. The deposits form the most western Cambrian deposits, and are in contact with Carboniferous formations upon their we'ltern side, owing to the extensive faulting. On the easte~n side of the fiat woods, there is an .extensive fault--the OosTANAULA-which line is characterized by the chain of low serrated ridges which cuts the "flatwoods" off from the Cambrian valleys to the east, and produces the repetition .of the same formations.
The thickness of these deposits is only conjectural, owing to the great repetition of the apparent mass on ac~ount of folclings and

38

GEOLOGY OF THE P.~LE0%0IC GROUP.

faulting::;, as the strata are fouud from almost horizontal position~: to almost vertical, and the development may be taken at anything from 3,000 to 6,000 feet, increasing towards Alabama. Thisphase is eharactered in part by thin, often grayish soils and poor ill drained lands, and in southern Floyd, the cotmty is sparsely settled, bnt farther north the land becomes better and is more thickly settled.
These shales of the Coosa valley eontain fossils, \Yhich from a point thiee miles southwest of Rome, Mr. C. D. \Valcott hai:i determined as belonging to the genus Olenoides, and cousequently belong to the Middle Cambrian series. The rocks of this basin were classified upon lithological grounds as the Coosa series of Prof.
E. A. Smith and adopted by lVIr. C. W. Hayes, before the determina-
tion of the fossils, by lVIr. Walcott. The shale ridges (which contain some sandstone) to the east of the basin below Rome apparently belong to a position beneath the shales to the west as well a& to the east of them, owing to the Oostananla fault upon their western side.

CONNASAUGA VALLEY PHASE.
The Oostanaula shales constitute a great accumnlation of red' green and variegated caleareous shales containing thin seams of sandstone sometimes quartzitic in the lower members, and darkbedded limestones in higher strata. The sandstones and .sorn.e interbedded shales show ripple marks and impressions of fucoids, indicating their shallow water origin. The limestones are often impure; sometimes they ate oolitic.. The maximum thickness doe& not seem to be less ihan from 4,000 to 6,000 feet. Sueh an accumulation of sediments represents changing conditions of deposition~ of long duration. As is seen to-day, upon the surface of the conntry the calcareous matter of the shales bas been mostly washed out, leaving the more siliceous matter to form varied soil, from sandy in the region of the sandstone members, clay lu::uns in more

OOSTANAULA SERIES.

39

calcareous regions, and again disintegrated chip3 of shale covered with thin soi~. The limestones often appear through t.he shales and clays along the streams. These are commonly dark colored, and are often traversed by a network of shaly films, which become apparent on weathering.
In Alabama, great isolated lentieular masses of qnartzi.te, or these beds with intercalated shales, form knobs and rugged mountains rising from 1,000 to 2,000 feet above the valleys (Smith) These are the 'vVeisner quartzite, and cannot yet be definitely connected with any set of beds in the great series. There is some possibility that these knobs and their shales as well as Indian mountain should be placed along with the Chilhowie serie8 beneath the Middle Cambrian strata.
Such a n1ass of sediments might be expected to be divisible into several diRtinct horizons. In Alabama, Prof. Smith says that the separation of the sandstone series of the Middle Cambrian serieo; from the higher shales, is not practicable, as the sandstones occur at many horizons. In Tennessee, Prof. Safford long ago separated the lower and upper beds into Knox Randstones and Knox shales, and more recently Mr. Hayes has renamefl them the Rome sandstones and Connasauga shale. A justification of this ch.ange of nomenclature might arise from the correlation of these deposits in the Cambrian system, whilst the overlying Knox (dolomite) series belongs to the Ordovician. In Tennessee, this division is more practicable than in Alabama, for massive beds of sandstone are there interbedded with many colored shales. In Georgia, the thick sandstones are of rarer occurrence; and the boundary lines are often obscure, although the resulting soils are sometimes more sandy. Topographically, the lower sandstone members of the Om;tanaula series occur in ipart in more or less low crested ridges, whilst the neighboring shales form valleys. But in many localities the shales form the ridges, as there is considerable variation in the beds, and in some places they are more or less metamorphic. This difference

40

GEOLOGY OF 'fHE PALEOZOIC GROUP.

may arise from including several divisions in the same systen. Indeed, at least three distinct paleontological horizons are included in the Knox shales (Walcott); whilst as yet there is no known paleontological ground for separatillg the Knox sandstones fron{ the upper members of this great series, part of which is Middle Cambrian. As fuller researches may lead to a new nomenclature for these divisions, and as simplicity and brevity are needed in this report, we cannot do better than to include all of the shaly series belonging to the middle and upper Cambrian under one cla.~s-the Oostanaula shales, and treat the whole a:; a unit on one map. This name has the advantage of avoiding confusion with the Knox limestones of the Ordovician system.
The position of the Oostanaula series in the great geological scale, as determined fiom the fullest information in the possessiOn of Mr. C. D. Walcott, is froRl the folio wing evidence:
In the northern suburb of Rome, from arenaceous shalei:i and clays aboYe the sandstones, fossils of the genus Bathyt~r,iscus were found, and from the sand stones Annelid remains. Professor Safford has also found fucoids in the sandstone. Bathyuriscus beds belong to the Middle Cambrian series. Below the Bathyuriscus beds, and between their exposures and the abrupt terminations of the shales, against the Carboniferous fault in Tennessee, and at apparently the snme horizon as the sandstones, J\ilr. 'Valcott found numerous specimens of Linguella, Obelella and Bathynri8cus. On the eastern side of and above the sandstone ridges, seven miles south of Home, a bed of limestone, intercalated with shales, contains Bathyu1isctts and Ptychopmia and species of Orthis-all being Middle Cambrian fauna. As already stated, the shales west of the Oostanaula fault contain Olenoides, and represent a lower division of the Middle Cambrian fauna. Accordingly, the 3andstone members must belong to or below the Middle Cambrian series. Mr. vValcott, our best paleontological authority upon the Cambrian fauna, to whom all our intricate questions in this department are referred, has further

OOSTANAULA SERIES.

41


.cletermined three subdivisions in the upper portion of the Middle Cambrian fauna, in the Knox shales of Tennessee, but says that these shales may be Upper Cambrian in part.
A short distance beyond Georgia, a mile south of Cleveland, 'Tennessee, in a railroad cut, there are six hundred or seven hundred feet of limestone beneath the cherty beds in the base of the Knox .dolomite (Ordovician) system.
These limestones contain Ptychopc11ia and other Cambrian fossils {Walcott).* It appears that the physical or lithological breaks in or adjacent to Georgia do not correspond to the change of fauna, as it often does, but with the changing life from the Middle Cambrian to the Upper, and from the Upper Cambrian to the Ordovician periods, the transition of physical conditions and growth of the continent was gradual; consequently, for accurate determinations, we must obtain the fossils, which are unfortunately not abundantly preserved, and the lithological characters alone are not sufficient guide. But in this economic survey, the study is simplified by .considering as a unit the Oostananla series, withouL a further introduction of new names or subdivisious. The Oostonaula series then embrace~:~ upper portions of the Middle, and all of the Upper Cambrian sediments as found in Georgia.

The Oostana.ula shales are internally greatly faulted as well as folded. The Oostanaula series occupies broad and narrow belts in the Coosa basin, and narrow belts occur in the Chickamauga and Chattooga drainage, the common feature often being the valley making dements. vVhere the rocks are calcareous they weather to rich red lands; where less calcareous the shaly soils are often thi'n and -of inferior quality.

~'The citations from Mr. Walcott are derived from references; in Correlation Papers of Cambrian System in Bulletin No. 81, United States Geological Survey; .and particularly from interviews and correspondence, he having visited the region .and collected all the evidence available on this special subject.

42

GEOLOGY OF THE PALEOZOIC (lROUP.

CHAPTER IV.

GENERAL CHARACTERISTICS OF THE ORDOVICIAN SYSTE~L

(LOWER SILURIAN OR CAMBRO-~ILURIAN.)

CONTENTS. TABLE. KNOX SERIES.
CHICKAMAUGA SERIEs-JHaclurea Limestone, Rockmart Slates.

TARLE.

SERIES.

FOR)IATIO.l'l.

Trenton (and Chazy))

{ Ro.ckmart Slate.

\ Chickamauga Deaton Ore Beds.

Hudson . . . . J

Mac! urea Limestone.

Calciferous

Knox Dolomite.

KNOX DOLOMITE.
This wide-Bpread series of rocks is distinctive) well named and not confusing. Economically it is one. of our most valuable formations, being rich in ores and building materials. It was first described by Prof. Safford, in Tennessee. It is characterized by magnesian limestones or dolomites. These are sometimes yery ma~sive, with indistinct stratification, (as in plate II.) and again they comprise thinner layers. Some ofthe beds are composed of simple limestones. These solid rocks are sometimes dark colored, but are oftener of light shades. The texture is compact or granular. The rocks present many degrees of purity: those containing sand weather to a coarse porons sandstone with rough surfaces; others,' rich in clay, soon break down, and superficial deposits of clays and loams are found; also great pockets of white clays occur in the deeply decayed rock. The result of weathering upon the disturbed rocko is to produce gentle, rounded undulations, and loamy soils most commonly of a reel color. (See plate VII. illustrating ore banks at Grady.)

PLAn: II.
KNOX DOLOMITE. At cut on Rome Railway, showing character of strata .

PLATE Ill.
KNOX DOLOMITE. Railway cut, one mile south of Dalton. Ledges of rock rising irregularly into the residual clay.

KNOX DOLO)IITE.
In the lower Knox dolomite, the accumulations of limonite, orbrown ore, manganese, kaolin and bauxite occur in large quantities.
Higher up in the Knox dolomite,' the beds are more apt to be siliceous and contain concretionary masses of chert oe flint. Sometimes the siliceous matter forms nodules of flint arranged in layers, or else in thick irregular pockets. Upon disintegration these cherty masses weather out into angular gravel or boulders,. which cover and protect the surface of the numerous steep ridges. The covering mantle of chert is usually superficial, and beneath it light colored siliceous clays are mor:;t common. Thus the cherty ridges and gray dolomite lands usually go together. Prof. Safford first discovered a characteristic of the chert in that it commonly contains rhomboidal cavities, which are molds arising from the removal, by solution, of crystalH of dolomite from the chert; also that fresh quarried cherty rocks still contain the crystalli7.ed mineral. The fossils are scarce, but still occasionally found.
Diffe1ent portions of the beds of the dolomite formation weather differently. Many exposures of the solid rock are well r:;hown in the cuts along the Rome railway. In some cases, the thin bedded and earthy strata weather the most readily, but in other places thick compact layers of dolomite rise up through other bed,; which are decayed to depth~:~ of scores of feet, showing very unequal weathering in apparently the same beds (sec fig. 1 and plate Ill.).
The compact beds shovv jointing or cracks, which favor weathering and the formation of rounded hummocks rising in relief. This . propensity for weathering has left the solid rock deeply covered by earth, and accessible only on the sides of occasional ridges or sometimes in valleys. Still i~ forms extensive exposures, as upon Ladd'.~ mountain, west of Cartersville, which is a characteristic but isolated dolomite ridge rising about 500 feet out of the plains (Plate IV.)
The depth of decayed covering is variable. Occasionally the :,;olid rock comes to near the surface. Again, in the residual earthy coverings, wells are often from 60 to 90 feet without reaching solicT:

44

GEOI,OGY OF THE PALEOZOIC GROUP.

rock, and the decayed rock debris at Oredell is 200 feet deep. This represents the removal of an enormous mass of calcareous matter from limestones, of which only the clay and earthy matter remains. 'The topography of ridges, undulations and valleys arises from atmospheric decay and removal of material from the disintegrated .strata, which often dip at low angles of 5 or 10, and rarely ex-ceeding 20 or 30.
It is difficult, as it is with all the rocks in this section, to deter mine the thickness of the formation. Mr. MeCutchen plaeed it at 5,000 feet. Mr. C. W. Hayes estimates it at 3,500 to 4,000 feet. In Alabama Prof. Smith assigns about 4,000 feet to it. Owing to the limestones being deeply covered with their disintegrated remains, the country composed of these rocks is mostly known in the form of cherty ridges and loamy valleys, andthe exposure of th~ stratified rocke is insufficient to make definite measurements of their thickness, for the disintegrated residual clays and cherts only form heterogeneous masses. However, east of V ann's valleys, southwest of Rome, it is not unreasonable to make an estimate of -!,000 feet as the thickness of the series.
Just east of the last named locality, a ridge is found composed of .a consolidated rock made up of angular fragments of dolomitic limestone. This structure implies an upper horizon in which the older rocks had become exposed to degradation, and out of their ruin the new beds were constructed. Fossils have not yet been found there, but the general topographic position indicates the lower part of the Knox dolomite series.
Many caverns occur in the Knox dolomite formations.
In Polk, Bartow and Floyd counties, the Knox series form broad undulations and cover a wide belt; but further north the formation occupies numerous belts, owing to faults, or produce subordinate :ridges in anticlinal valleys.

PLATE IV.
LADD'S MOUNTAIN (BARTO COUNTY ), sao feet high, showing form of riJ ges produced by weathering of Kn ox dolomite. Cotton fi eld in foreground .

CHICKAMAUGA SERIES.

45

Fuller details of this formation may be found in the local distribution given in succeeding pages. Other information as to minerals and thelr compositions is given in the Economic part of the report.
CHICKAMAUGA SERIES.
This series of rocks comprises such of the Hudson, Trenton and Chazy formations as occur in Georgia. Their separation in the
southern Appalachian region has always been a source of difficulty,..
as the physical and lithological structure in some places permit of' separation, whilst in other cases they become a unit. Nor can exact parallelism be established. Hence, the adoption J>f Dr. Hayes' nomenclature.* The rocks, as a unit, are best developed in the.Chickamauga valley, as also in Whitfield county, .although in Polk county the separation into Safford's Maclurea limestone and Hayes' Rockmart slates is very distinct.
The Chickamauga series west of Taylor's ridge is notably an impure bluish limestone, often in thin beds and more or less flaggy. These limestones are frequently fossiliferous. In places, the rocks are intercalated with beds of shale. When the calcareous matter is dissolved away from the limestone, owing to weathering processes, prominent ledges of flaggy material of sbaly character remain in relief. These limestones are usually at low angles from 10 to 20, although steep in places, and often protrude through the soil and form the rocky pavements of the country. The Chickamauga series characterizes narrow valleys and low rocky ridges ; this formation also extends upward often to a considerable elevation in the neighboring mountain ridges, which are capped by more durable rocks. Sometimes the rocks do not appear through the soil, especially when the outcrop is narrow and in valleys at the foot of mountains. The soil which.results. from the decay of these J'ockR is usually a stiff, reddish or brownish clay,. forming some of the _most fertile
'*Bull. Geol. Soc. Am. Vol. II., p. 143.

46

ROCKliiAR'.r SLATER.

lands of Georgia. In this part of Georgia, the thickness is from 1,200 to 1,800 feet.
In Polk county, the lower subdivision or the Maclnrea limestone forms massive beds, some of which are remarkably pure limestone, -often fine granular in texture, and from light to dark gmy in color. In that district, it is o;lightly metamorphic, forming gray and colored marbles. In weathering, they do not u5ually disintegrate but have their surface worn away by solution, thus producing rounded hummocks (see plate I, whete these hummocks have been covered by higher matetials now removed), rising up in the valleys and sometimes forming considerable hillocks, even to an elevation of one to two hunched feet. The formation is often characterized by caverns. This portion of the Chickamaup;a series has probably a thickne:;s of' 600 or 800 feet.
The Deaton ore beds, occurring northeast of Rockmart, overlie the Maclurea limestone at low angles. These beds are ferruginous limestones, varying in thickness from a few inches to a few feet. They are dark gray, fine grained and compact, and sometime contain 30 per cent of iron. More commonly the beds arc earthy and weather into ferruginous clay, or angular slabs of iron ore. The thickneas is from 100 to 200 feet. Similar bed;; occur in vVhitfielcl county. These ore heels represent some portion of Safford's iron-limestone series in Tennessee. (See plate I.)
The Rockmar"t Slates of Polk and adjacent counties form the upper member of the Chickamauga series. The rocks dip at angles varying from 20 to 40 near Rockmart, and approach the vertical, near the Carterroville fault, a few miles to the south. Farther west, they cover the Maclnrea limestones on a rather flat rolling country, .although about Rockmart they form ridges. The slates weather to a grayish, reddish or variegated color, and are broken into small chips covered by thin soil. They are semi-metamorphic and in places have a cleavable fissile structure. Some of the upper heels, -which are not fissile, weather into a bed of beautiful clay, capable

CHICKAMAUGA SERIES.

47

Qf being carved into ornaments, or the so-called Caenstone. The
estimated thickness is 1,200 feet. Another feature of the Chickmanga er i :-.;1 in thn ridges south of
Rockmart, i.s a heavy bed of breccia 90mpo \ l .,(' nu g ular and sub-
angular chert with some slate. This i. I)) 11 t.' 1 in t 1~ hard rock
whl It lws h '<' II t'1sed f(>t ,mill t n . ~l:'hi : lll'eocin poin ts < au p > b
f.(h st u1lmnc! n ~b e do e o-f th Kn d111'0mite, jtl'fit flS Lit e l>r ill
nt th bu. l uf' tb ]\Ill x 11 lotllii. " (u J d 11 puoo 44) point d to a di atu .!I)Hll(' , ,thnut ti J~ lo~e rJf t he \ un btian }) l'tod, (hr t h e deP sit~, altnongL oxpo c I to >nl. ~t limit d xt nt , I eJ n to tbu has f t lw 'b i I an nngu r; rlf!s.
The local features of the Chickamauga series will be noted in
later chapters on the various counties.



48

GEOLOGY OF THE PALEZOIC GROUP.

CHAPTER V.
GENERAL CHARQATElUSTICS OF THE SILURIAN SYSTEM.
RED MOUNTAIN SERIES.
The Silurian system overlying the Chickamauga limestone is only imperfectly represented in the southern Appalachian region by a series of rocks which Safford, in Tennessee, described under the names of Clinch mountain sandstone, White Oak mountain sandFtone, and the Dyestone group; and Smith, of Alabama,. named the Red mountain, or Clinton series, which Mr. Hayes has renamed Rockwood. All of these rocks appear to belong to horizons, including the Medina, Clinton and probably lower Niagara series, with the upper portion of the Siluriat1 system wanting. There is no ground for local subdiYisions, although great variation in rock masses occnr. Thus, in Murray county, on Rocky Face, and other ridges, massive sandstones, capping the lower shales, give rise to bold, high but narrow ridges. Taylor's ridge, to the westward, is of a similar characterl but with a diminution or sandstones. \Vestward of this last ridge the sandstones become less abundant and are replaced by thick deposits of shale, which are seen in "Shinbone ridge" (or the foot-hills of the Lookout_plateau). Here the ridges are natTow and low, but with interrupted points rising two or three hundred feet aboye the valleys, owing to their protection by Sub-Carboniferous cherts. On account of the strata inclining at considerable angles, usually not exceeding 30, bnt sometimes nearly vertical, the characteristic feature of the
formation is that of narrow ridges. (See plate V opposite.)
The mountains and ridges are portions of synclinal folds, which, for jnstance, pass under the Carboniferous rocks of Lookout mountain. Thus, the formation usually bounds anticlinal valleys, the centers of which are occupied by older formations.


PLATE V.
SHINBONE RIDGE, (Red Mcmtain Series, etc.), a lo ng th e foot of Lookout Mountain, at Rising Fawn.

RED MOUNTAIN SERIES.

49

The sandstones are often massive, and vary in color from light gray to brown and red. The shales are commonly fissile, in thin beds, amongst which there are intercalated, at various horizons, thick layers of sandy shale which passinto fiaggy sandstone; sometimes there are thin beds of fossiliferous sandstone, as well as beds of hematite or red fossil ore, which renders this formation extremely valuable. These iton ores occur somewhat above the medial horizon. The iron ore beds are commonly made up of masses of shells converted into oxide of iron, leaving the structure of the shells, amongst which there are flattened concretionary nodules. Above the drainage level, this "fossil ore" does not usually contain much calcareous matter, but below the water levels, where it has not been leached out, there iH sufficient calcareous matter for self-fluxing, and the calcareous layers are better pre~erved than near the surface. The total thickness of the Jormation in Georgia reaches from 800 to 1,100 feet, and is best shown at the end of Pigeon mountain, where it is exposed by railway cuts across the whole formation, dipping regularly at about 8 to the east of southeast. In Alabama, the formation dwindles to about 100 feet in thickness.
A~; a surface feature the Red Mountain series forms only narrow belts. The rocks appear to lie comformably upon the Chickamauga limestones. which often rise high in the sides of the mountain. Overlying the Red Mountain series, a thin deposit of black shales, belonging to (probably the upper part of) the Devonian system, occurs. Whilst unconformity is not recognizable, yet it is probable on account of the great gap apparent in the geological succession.

50

GEOLOGY OF THE PALEOZOIC GROUP.

CHAPTER VI.
GENERAL CHARACTERISTICS OF THE DEVONIAN SYSTEM.
CHATTANOOGA BLACK SHALE.
The Devonian system in Georgia is represented by only from ten to twenty-five feet of black shales, which are valley making. At the surface they are rarely exposed, owing to the usual covering of debris from the adjacent ridges. Still, where the. streams cut across the formations, the black shales are usually found between the Red Mountain beds and overlying cherty limestones. In Alabama, they dwindle to a thickness of ten feet, whilst in Tennessee the same beds increase to a thickness of 100 feet. The top layer" of the shale become lighter colored and contain rounded concretions. At some points, the black shales are wanting, thus permittiug the contact of the Silmian and Carboniferous systems.
This shale is commonly mistaken for coal. It is often characterized by sulphur and mineral springs.

CARBONIFEROUS SYSTEM.

51

CHAPTER VII.
GENERAL CHARACTERISTICS OF THE CARBONIFEROUS SYSTEM'.
CONTENTS.
CoAL MEASURES. MOUNTAIN LIMESTONE. FLOYD SHALE. FOR1' PAYNE CHERT.
The Lower or Sub-Carbonifero u erie. i xtensively developed' in northwestern Georgia in thr e <Jjffer n phases. In the valleys adjacent to the Coal Measure ridges, the M untain Limestones are bounded by cherty ridges of the Fort Payne series with the intermediate Floyd shales wanting. But east of Taylor's ridge the Sub-Carboniferous valleys are carved out of the Floyd shales,, whilst the ridges are covered with the Fort Payne chert.
FORT PAYNE CHERT.
'l'ht! .Eot't Payne chert n.c;ists of a illceous liJnei!rton mor Ol' '
a les fill with Letty OD,Cl' ti ns. Sometimes the bert 0 OJ' hl
lay 1;S butn aiuitisintheformofnodllle . Th "lc:.u ou. matter is d iss lvcd otrb upon t.b. w athe iug of the rocks, leaving the r~ourrtry overed wit:b a cherty grave l mantle, which favo1. th p1 duction of ridges. This h 1 ,i mo c ot 1 ss porous from the J'emain. of f siJ iulplsRi ns. It lies upon th blacl . hal~ o
t,he D von ian rsystem, except where it is wnuting. .Ea b. f Taylor's'
ridge, the rocks at tb surfa ti rm rest d ridge~;. West f th " hicka.m~tu a valley they f(Jl'Jn ridges oov reel with h rt a.djace-u tJ
to the valle s of the Mountain Limestone. These cherty hills1 ofte11 pl'otect tbe it n bearing shales f tho Red Mountain ecies.. (See p,late V .) Th e nhiokness of theJormation varie. from 24 feet

;)2

GEOLOGY OF THE PALEOZOIC GROUP.

to 510 feet. In this formation fossils are found in many places, and in some horizons crinoidal rocks abound. Upon the map, it is not practicable to represent the belt of this series, whi~h everywhere bounds the Mountain Limestone on the one hand, and forms the ridges adjacent to the Floyd shales on th e other. A few outlying patches of this series cap some cutlying ridges of Lower Paleozoic rock in the Coosa drainage.
FLOYD SHALES.
These shales havP the greatest development m Floyd county. They are composed of black or yellowish shales, or a dark blue calcareous shale, and beds of limestone. The beds of lim estone are \'er y toRsilifcrou wes.t, of I m . Th.i Jormation con stitutes a co n.~iclerahl e poJ:tio n uf 1'11e 11flntw od "()f the saba. in, ani forms
<:ump::nativ Jy leve l lo.r1d. The rocks are more or i lls d isturbed , hul haV' uu estim1.1tecl thi ku f 1 ,1) f t . TI1 e ~o il ove1 t bc
" flatwoods" are usually thin and away from th e calcareous laye,s often po or. Amongst these shales there are some sandstones which may be the equivalent of the Oxmoor sandstone of A labama.
THE MOU NTAIN LlMESTONE.
Th i: II P!l r m ' mber of t.he Sub- a rbo nif' t'O il s r.i . i ::t pur blue Ii me "to ne with a t1 v J pmen t of al>out 90 fe t it1 hlcknes-;. I I
fi H' Dh~ bhe sides of th ' n ouu tai.t1 wbi h a1 ar ped with oa l Mclts-
lll'e: , a nd ext u I: d wn into t h vnlJ y . I is }I I ighl (o. . ili fel'o ns rock , rich in riooicl ste ms. W ithin the lim est. n ~ cnt numntnin u bcrl of !'lanu to n , is ~ llJH I. T lt upp 'r 1 r tiou of t h li ne Lo 11e be nw ' somew hat e~:ut h y a: i u.p proa b t h sbtd . of th onl M asure,. .A: a ..urth' ro k , it is most cum;pi U!usly d ' VP IO] I at Lhe e nd of Pjg on rn Hm ta i n. T he M uu tu..in L imeto ne usutlll y Li a L 1 w a ngles beuca h th Coal Measpr c ba in f:l of the mountain plateaus.
THE COAL MEASrR ES.
Th e Coal Measures lie in synclinal basins capping Sand, Lookout

PLAT~~ VJ.
LOOKOUT MOUNTAIN, Seen from Ri si ng F a wn (1,000 feet hi gh) , show ing the escapement of conglomerate capping and protectin g the plateau.

COAL MEASURES.

50

and Pigeon mountains. The same rocks of these formations also cap one or two ridges to the eastward of Taylor's ridge. These outlying fragments are neceRsary, in showing the former wide extension of the Coal Measures which have been removed by denudation (see pages 18 and 25). In contrast with the rugged character of the Red Mountain series, the topographic featnres of the Coal Measures are mountain plateaus, which have been preserved, owing to the nearly horizontal hard sandstones so largely prominent in the series. The total thickness of the Coal Measures in Georgia reaches from 1,400 to 1,600 feet upon Lookout mountain, and to halfthat thickness on Sand mountain. The Coal Measures may be divided into the Lower Coal Measures and the Upper Coal Measures. The Lower Coal Measures on Lookout mountain have a thickness of 600 feet. This is characterized by shales, succeeded by 40 feet or less of sandstone or fine grained conglomerate and another deposit of shale, followed by heavy sandstones and eonglomerate which reach a thickness of from 175 to perhaps even 250 feet. Included in this succession of rocks, there are two beds of coal, one of which may be workabie in places. This conglomerate forms the striking feature of Lookout mountain, as it sunounds that plateau as a battlement wall, broken into by occasional streams (plate VI.). The rocks commonly dip at low angles from both sides into the mountains, and form a basin. At some few points, however, the disturbance;-; have been great, and have thrown the rocks into steeply inclined positions.
The Upper Coal Measures consist of a succession of shales ~vith bedded sandstones, and reach a thickness of 840 feet, including seven seams of coal of variable thickness from fom feet to a few inches. As the upper part of the series is made up of shales, these deposits have suffered extensive erosion, but remnants of the higher beds still constitute the productive Coal Measures of Lookout mountain.
The Coal Measures on Sand mountain have a somewhat different

.54

GEOLOGY OF THE PALEOZOIC GROUP,

physical appearance, and are represented by about 500 feet of shales :and sandy shales; with both the lower and upper conglomerates, here mostly sandstone, which are less developed than on Lookout mountain. The Lower Coal Measures contain seven seams of coal, :some of which,however, are thin. Above these Lower Coal Measures :about 300 feet of the Upper Coal Measures are composed of shales with some thin sandstones and sandy shales; these deposits are followed by a capping of sandstone. In this upper series there is at least one seam of coal.
It is noticeable that the conglomerate, or its equivalent in the form of sandstone on Sand mountain, occurs above the most pro-ductive part of the Coal Measures in place of below, as on Lookout mountain and most other regions. It will be seen in comparison with the coal fields of Alabama that the volume of the Coal Measures is greatly reduced in Georgia, for the thickness in Alabama is 5,525 feet, whilst in Tennessee the series has a thickness of from 200 to 2,500 feet.
The conglomerate consists of a coarse sandstone, occasionlly charged with pebbles, usnally not greater than from half to threefourths of an inch in diameter. The beds are sometimes thin, but occasionally form masses from 10 to 75 feet in thickness. Tlie shales may be argillaceous and constitute a fire clay, or in places they are sandy and pass into pure sandstones. In some places, the shales are ferruginous and weather to a red color; in other places they are of a bluish tint.
In order to better understand the structure of the Coal Measures in Georgia, reference to figure 14 will show a section across the formation and the relationship of the Carboniferous system to the other formations.

Scale

3 Mile.s

Vi'rll'cal

100 Feet

FIGURE 14.-Section from Sand to Pigeon Mountoins; C, Coal Measures; Om, Mountain Limestone; Heavy line is Devonian; R, Red Mountain; Ch, Chickamauga; K, Knox series.

RECENT FORMATIONS.

55

CHAPTER VIII.
HECENT FORMATIONS, AND EVOLUTION OF NORTRWESTERN GEOl'tGIA.
LAFAYETTE(?) AND MODERN.
In the decayed rock accumulations over the whole Paleozoic belt have been in process of formation throughout most of the periods from the Carboniferous t.o the present day, but we have one remnant of a later formation than the Coal Measures. This remnant -consists of the deposits of graYel and loam found at altitudes from 50 to 150 feet above the waters of the Coosa basin. These gravels are the equivalent of the Lafayette (?) Eeries of southern Georgia, hut. there accumulations have been latgely removed by subsequent ,Jenndation, so they are mostly seen to-day upon the hills within two miles of the rivers. In the Coosa basin, the gravels do not occur at elevations higher than 800 feet above the sea; however, in the higber country, amongst the crystalline rocks to the east, along .the tributaries of the Coosa and the Tennessee rivers, apparently, the r;ame gravels occur to 100 feet above the modern streams, at .elevations from 1,500 to 2,000 feet above the sea. These deposits modify the agricultural features of the country. Along the Chickamauga and other valleys west of the Coosa basin, in Georgia, the gravels and loams have not been recognized-a rather remarkable absence. The gravels are usually composed of quartz, derived from the crystalline rocks, with occasional pebbles of local material. 'fheir position above the rivers is indicative that they could not l1ave been so deposited from the swollen volumes of the streams,

56

GEOLOGY OF THE PALEOZOIC GROUP.

but their deposition was favored by the slack water of the estuaricl" occasioned by the submergence of the southeastern part of the continent, in this region, to a depth of nearly 800 feet. The occurrence of the same accumulations at high elevations in thr mountainH to the east is probably an indication of considerable warping movement of the earth's crust sinee the depositions of the Pleistocene epoch. It must be emphasized, however, that the deposits have been largely removed by denudations ~mbsequent to thPir aeeumulations during the late subsidence of the laud.
The only modern formations represented is the river alluvium of the present streams, which sometime;; has a width of a mile or more, adjacent to the principal rivers; but is not greatly developed along the smaller streams. There are remnants of terraceo;, butthese belong to the Lafayette series. The continuing decay of the older rocks, constituting the common soil of northwestern Georgia cannot, of course, be regarded as a distinct formation.
EVOLUTION OF NORTHWESTERN GEORGIA.
From the generalized descriptions of the geological formation;; of the. Paleozoic belt of Georgia, florne interesting knowledge as to the growth of the continent may be inferred. At the close of the Archrean era, or rather at the close of those periods which produced the more recent crystalline rookH, the crystalline belt to tlw southeast constituted elevated land from which t.hc water:': were washing the decaying products into a sea eovering the now Paleozoic belt. Fragments of the old shore lines and remnant,., of riYer deposits are occasionally 13een in tho:;e masset~ of 13andstoue, ,;uch a:,; I udian mountain; however, the :mbsequent physical c:hange:; have obliterated these early c:onditions of the growth of northwestern Georgia, leaving only unmistakable remnants of the Middle Cambrian period in the thick shaleo; of the Oostanaula series. These shales were in part an off-shore deposit, but probably a not difltant accumulation, as shown by their sandy character; still, at times,

EVOLU'l'ION OF NOR'l'J-1\\'ESTERN <mOROIA .

57

the waters were sufficiently clear to allow of the accumulation of impure limestones. In the later Cambrian days, there appears to have been some interruption, so that at the beginning of the Lower Silurian, or Ordovician petiod, some traces of unconformity are recognizable in the breccias which are found associated with the Knox dolomite at a few localities. The shaleR of the Cambrian period, however, extended from the old coast line, on the eastern side of the Coosa valley, all the way to the farthest limit of Georgia. With the advent of the early Ordovician period, the sea was freer from the muddy deposits coming down from the highlands to the east, and upon its floor was aceumulated an enormous thickness of limestones, with which, however, some clays and sands were commingled. The limestones were mostly turned into dolomite. It wa<> in this period that the iron, manganese and beauxite ores were deposited among the forming limestones. At the close of the Knox dolomite epoch there appeared to be local interruptions, as shown by the presence of breccias near the base of the Chickamauga series in Polk county. But the Chickamauga sea was characterized by an influx of more or less muddy waters, which interfered with the calcareous growths. This influx, however, was more or less interrupted, as some beds of pure limestone were formed in basins protected from the muddy streams. ~-\ fter the elose of the Chickamauga epoch, the Paleozoic sea was flooded with muddy waters, carrying down the sands and clays which now form the Red Mountain series. The shore lines of this epoch had moved many miles westward of those of the earlier Cambrian days, and are preserved in the heavy sandstone deposits of the eastern ridges of the Red Mountain series, whilst the Red Mountain series further westward i~> composed mostly of clays which were carried into deeper water. However, along with these deposits some beds of limestone were formed. The upper part of the Silurian system is not represented, KO that it is probable that for a considerable length of time the whole of northwestern Georgia became dry land, and this condition

.58

GEOLOGY OF THE PALEOZOIC GROUIJ,

continued far into the Devonian period, which is represented by -only a few feet of shales, although the Devonian system, elsewhere on the continent, reaches a thickness of 13,000 feet.
With the advent of the Carboniferous period, the waters of north western Georgia, driven farther seaward by the growth of the land, became the home of a rich m~rine fauna, which has built up the great deposits of limestones. However, into a portion of that sea, enormous quantities of mud were carried and locally deposited, as in Floyd county. Perhaps, elsewhere in the State, there was a temporary elevation of the lowest Carb:miferous rocks, which, however, were not subjected to great erosion, as the unconformity -between the limestones i"' not apparent, eYen where the shales are wanting. Later on, the Sub-Carboniferous sea appears to have gradually become muddy, and the basins becam_e filled with the t>hales and sandstones of the Coal Measures, which occasionally gave rise to swamps, producing in Georgia at least nine beds of coal, .separated, however, with mechanical deposits washed down from the outward growing shore line of the State. It is probable that the Sub-Carboniferous Bet\ during its early days extended over most of northwest Georgia, as outlying fragments are met with. The Coal Measure Heries extended ten or twelve miles eastward of Pigeon mountain, as shown by outlines on Little Sanrl and Rocky mountains east of Taylor's ridge. These indicate an enormous erosion since the Carboniferous period.
Throughout the Paleozoic era, the succesHion of strata appear:; to have suffered no other disturbance than occasional interruptionf:l, owing to temporary rising and sinking of the lands, without any great disturbances in the position of the strata. The faulting, overthrowing and folding of the f(Hmation8, which Ul'e represented by the mountains and valleys of to-day, did not take place until .after the clo8e of the Coal epoch; still sufficient time has elapsed to permit atmospheric and ri\'et erosion to remove thousands of feet of the various Paleozoic strata, and lea\e the present valleyf::,

DENUDATION OF LAND.

59

ridges and mountains, forined in a large measure, owing to the

durability and position of the strata favoring or retarding the

grinding away of the country, by subsequent rains storming the

rocks through several geological ages, as shown in figure 15.

,

......--------

--.f:.
.

,_...-... - .....-..-.

FIGURE 15.-Tbis shows a section of fifteen miles, from which the Coal Measures and other formations have been removed by denudation, with the formation of valleys. The denuded beds from Coal Measures (C) to lVIiddle Cambrian (Mo), care represented by dotted lines. F, great faults.
From the Coal epoch to the Lafayette (which is probably Pliocene) northwestern Georgia appears to have been continuously dry land, followed by the submergence and re-elevation of the Lafayette epoch, since the beginning of which, howev~r, the mountains to the eastward pf the Coosa basin have been probably elevated to a greater extent, compared with the country to the west, than before that time. But this study of physical geography .cf the past and the growth of this section of the State cannot be properly separated from the growth of the adjacent States.

60

GEOLOGY <H' THE PALEOZOIC GROUP .

CHAPTER IX.
PHYSICAL FEATURES OF THE COUNTRY UNDERLAID BY PALEOZOIU ROCKS.
INPOLK, FLOYD, BARTOW, G()RDON, )IURRAY, WHITFIELD, CATOOSA, CHATTOOGA,. WALKER AND D~DE COUNTIES.
CONTENTS.
GENERAL FEATURES 01' ~1) 'l'HE CoosA V ALI,EY AND rTs EASTERN BouNDA-RIES, (2) NoRTHWEST 01' THE CoosA BASIN.
CHARACTERISTICS 01' RIVERS AND STREAM:;. MINOR PHYSICAL FEATURES: In Polk, Floyd, Bartow, Gordon, Murray, "Whit-
field; Catoosa, Walker and Dade counties. LAKELETS, SINKS, AND C,~VES. TABLE OI' ALTITUDES. GENERAL FE\TURilS 01<' THE, COOSA VALLEY AND IT3 EASTERN BOUNDARY~
This definition is not strictly accurate, as in places metamorphism has somewhat affected both the Cambrian and Ordovician rocks, .in contact with the more highly altered rock to the east, adjacent to the great Cartersville fault.
N ortbwest of this fault line, in the Coosa basin, the general altitude of the broad rolling vall~ys is from 850 to 900, occasionally rising to 1,000 feet above the sea, as shown by the 250 feet contours on the geological map. Across Bartow, Gordon and Murray countieR, the country is somewhat lower, with a general altitude from 750 to 850 feet, occasionally rising to 900 feet. This general valley country is sharply defined by 'mountains, which enter Polk county, between one and two miles south of Esom Hill, with an altitude between 1,200 and 1,300 feet above the sea,

PHYSICAL FEATURES.

Gl

and constitute a defined range along the southern edge of the country, passing neat Felton, Hightower (Mills), to Simpson's Mills about four miles south of Rockmart. This range of hills is a conspicuous feature across the country, which for long distances forms the prominent landscape of "Dug Down Mountain." The outliu~ is somewhat regular and broken to only an unimportant degree, as the water-shed dividing the streams flowing north from those flowing south is close to the brow of the range.
In the broken country, southeast of Rockmart, the regular features of this range of crystalline rocks is lost, as some of the Paleozoic rocks rise (as in Carnes' Mountain 1,291 feet above tide) higher than the more metamorphic rocks to the south and east. From this point the Paleozoic valleys are bounded by lower metamorphic hills, or rather the ends of numerous spurs, left. between the streams flowing northward to the Etowah river. These hills swing around and leave an embayment of the valley southeast of Cartersville, with some isolated points upon its northern side, rising to about 1,500 feet above the sea.
From 1he vicinity of Cartersville, the Paleozoic valley is again bounded by more regular ranges of bills, with occasional knous rising from 1,300 to 1,500 feet above the sea, as spurs of Pine Log mountain, which, farther north, rises to 1,800 feet. Three or fonr miles east of the valley, upon the eastern boundary of Bartow county_, these mountains rise to over 2,300 feet.
East of Pine Log Postoffice, Pine Log creek forms an embayment in the chain of hills, changing the direction of the range, which, however, soon trends again to the north, and enters Gordon county near Fainnount. For many miles south and north of thiH point the valley is sharply defined by an apparently regular range of mountains, which rises from 1,400 to oyer 1,500 feet above tide, with the next embayment made by Talking Rock creek, two or three miles above its discharge into Coosa river. A contrast is noted between relationship of this creek and the tiver, as they pass

62

GEOLOGY OF THE PALEOZOIC GROUP.

through the mountains; the creek has produced a large valley in the mountains, whilst the river cuts through the range without greatly modifying its outline, thus giving the valley a newer appearance.
The range of mountains, still of the same general height, enters Murray county, passes by Dennis and eastward of Fort Mountain Postoffice. Here is a chain crossing the country obliquely, with its highest point rising to 2,827 feet. The name Fort Mountain is given on account of the remains of a prehistoric (supposed to be Spanish) zigzag wall built across the end of one of its E~pnrs like a stone breastwork. Fort mountain, with its northeastward trend, is separated from Cohutta mountain by the valley of Holly meek, forming a deep embayment in the general mountain wall which bounds the eastern side of the great Coosa valley. The highest point of Cohutta mountains (Bald mountain) is 4,450 feet above the sea. Northward, the mount~ins continue to form a prominent boundary to the valley, although declining in elevation. to 1,500 feet or less, and at a point about four miles west of the Murray-Fannin line, they cross into Tennessee.
From Fort mountain northward, the trend of the ridges is usnally at broad angles (up to 90) to the trend of the hills forming the boundary of the Coosa valley, thus showing a notable and abrupt truncation of the mountain spurs; which features mark the great fault line that bounds the unmetamorphic Paleozoic region of" Georgia.
Owing to the features just described, no doubt is left as to the boundary of the unaltered Paleozoic systems, in the country under report, as shown at M and M in figures 16 and 17 on, page 63.

.2.
FIGURE 16.-Section showing undulations of profile in the middle portiun of the Coosa basin in Georgia.
FIGURE 17.-Section across the northern portion of the Coosa basin between Rocky Face and Cohutta Mountains (M).
The subordinate ridges in the valley are mostly composed of Knox dolomite, and rise from 100 to 400 feet high. The eastern limit of the valley is commonly bounded by high rqounta,ins of metamorphic !'ocks, !lflq the western by bold ridges of the Paleozoic /?:roup.



64

GEOLOGY 0]' THE PALE07.0IC GROFP.

NORTHWEHT OF TilE COOSA B .\HIN.
Whilst the valleys west of the Coosa basin are similat to those to the east, in respect to undulating plains and low ridgeR, yet there is a marked contrast in the high mountain ranges and plateaus to the
west. The most eastern of these high ranges is Rocky Face ot
Chattoogata and its ?:igzag continuations and repetitions through Horn's and John's mountains, skipping to Lavender mountain, a 8pur of Taylor's Ridge. Taylor'H Ridge, which, with its continuation, White Oak mountain, forms a second 8harp-backed ridge with elevations fi'Om 600 to 800 feet above the Yalleys. To the northweRt, Lookout and Sand mountains fotm el~vated tahle-lands from 700 to 1,400 feet ahoYc the valleys, 'rhich have an altitude of 7;)0 to 900 feet above the sea.
A general view of this part of the State may be seen in the profiles of the geological sections upon the geological map or in figure 15, page 59.

1'HE CHARACTERISTICS OF THI" RIVERS AND STREAI\iS ,
The general Coosa valley, with its subordinate valleys, is a portion of a great mountain basin or trough crossing East Tennessee, Georgia, and extending into Alabama. Entering the valley from Tennessee, the Connasauga flows by a very circuitous course to a point about four miles northeast of Calhoun, following the general course of the mountain valley. At the point jnst indicated, this river is joined by the Coof;awattee-the two forming the Oostanaula. Near Resaca, the appeamnce of the valley is that the original Connasauga river was once continuous with the Oostanaula, and that the Coosawattee should be considered as the tributary, crossing the trend of all the ridgeH. The Oostanai.da, with the same meandering course, keeps close upon the western side of the valley to Rome, where, being joined by the Etowah crossii1g the ridges, it becomes the Coosa. The smaller streams throughout Whitfielrl and Murray counties are mostly subordinate to the trenil of thP

CHARACTER OF THE STREAMS.

65

valleys, and are consequently longitudinal, only crossing the trend -Qf the ridges to a small extent, and flowing with a south ward direction. South of the Coosawattee, several creeks flow northwestward across the primary direction of the ridges, thus producing a broken country.
The creeks which join the Etowah flow from one side or the other in the general trend of valleys, northeast and southwestward.
Below Rome the Coosa valley is broad and constitutes the "flat woods" with unimportant streams. The embayment of the great mountain valleys, in Polk county, is marked by only one large stream-Big Cedar creek and its tributaries.
A characteristic of all these streams is their ancient appearance. In a general way, the channels of the larger rivers are no greater than can be filled during floods,* and the smaller streams almost flow Dn top of the ground; that is, without deep river beds. Still the adjacent hills are often high, but manifestly they have been fashioned more by atmospheric erosions than by the ri'Zers, for they are very deeply sculptured. ~Whilst this ancient appearance is everywhere conspicuous, with the absence of abrupt topographic features, yet the shallowness of the channels might bespeak their newness. The conclusions which ate drawn from the topographic features point to the great antiquity of the streams, and that long ago they had reached the base level of erosion; that is to say, the erosion had continued until the streams could no longer deepen their channels, and consequently their work consisted in broadening the valleys and softening the outlines of the higher lands. But only to a li.tnited extent were the processes of erosion succeeded by deposition of the highl.mcl muds washed clown by the smaller streams. In recent geological changes of level, the streams became more sluggish, and, to a limited extent, river deposits were formed high up upon their banks (from 80 to 150 feet above the modern
~' At Rome, floods overflow the plains to various depths. A flood of 1886 caused the water to rise 41 feet above low stages.
(6)



66

GEOLOGY OF THE PALEOZOIC GROUP.

rivers), according to their locality. But the subsequent elevation of the continent lowered the waters; and now we find the streams digging out their channels to a small extent, for land is again higher than during the long ages required in moulding out the general topography of the valleys of northwest Georgia. Be this as it may, the fact remains tbat, although the rivers flow through broad, rolling valleys, there is a common absence of deep channels and gorges throughout the Paleozoic belt.
The streams amongst the mountains and ridges beyond the Coosa valley also indicate the extreme antiquity of the base level of erosion, and flow through the Yalleys which have been extensively broadened by lateral action of atmospheric erosion. At the end of' John's mountain, on the east side of Taylor's ridge, the Armuchee creek breaks through mountains of the Red Mountain series, and iR joined by Texas creek, flowing between Lavender mountain and the main ridge of Taylor's mountain. East of Taylor's ridge, in Whitfield county, the East Chickamauga river rises between it and the Rocky Face, but has cut through the ridge at Ringgold. The valleys between Taylor's ridge and Lookout mountain are drained by the branches of the Chickamauga creek, flowing to the northward, and the Chattooga river flowing to the southward. These rivers, whilst reducing the base level of erosion somewhat, are still flowing near the surface of the valley like those of the Coosa basin. Some considerable creeks rise upon the Lookout plateau, and cut, longitudinally, into the mountain, thus making the summit of the plateau rugged. Lookout creek and Nickajack creek are similar creeks to thof'e upon the plateau, but they have already cut deep, broad valleys to near the base level of erosion. As the accumulation of river deposits throughout thio; o;eetiuu are, u::;ually, of no great thickness or extent (the soils of the valleys being mostly residual from the decay of the rocks), it would appear, from the present character of the streams, that the modern, slight elevation, above the base level of erosion, dates back but a very short time ~

..

PHYHICAL FEATURES OF POLK COUNTY.

67

or, in other words, that the land of northwestern Georgia has been lately elevated to a moderate extent above the ancient level as, compared with the sea, during which time the streams, being no longer able to deepen their channels, have favored the widening out of the valleys down to their base level of erosion ; accordingly, the rolling plains were produced. The streams at many points now flow over rocky shoals on account of the recent elevation of the region just referred to, and give rise to a number of water powers. The principal waterfall is Lula on Lookout mountain. (See Local Features of Walker county, page 73.)
THE MINOR PHY3ICAL FEATURES.
I N POLK COUNTY.
The older geological formations cover most of Polk county, and occupy an embayment in the metamorphic girdle, which swings around in that region to the westward and changes the direction <1f the ancient Paleozoic valley. The features are closely related to the geological structure, being dependent upon the characters of the rocks, the dip and folding of the strata and the subsequent degradation of the land.
The boldest feature in the county is the Indian mountain, partly in Alabama, rising to 1,982 feet above tide, or 1,100 above the valley at Etna. It is a mass about seven miles long, but that -portion with an altitude of 1,500 feet, is not over three miles in length.
From this mass, the valleys trend east of north, the principal being that of Etna, and its continuation into the Little Cedar creek, with narrow ridges to the east rising to 200 or 300 feet above the drainage. The northwestern portion of the county is somewhat rugged, from the prevalence of gray cherty hills o,r ridges. The northern central portion of the county is more or less level, with rounded outlines and ridges. The same is_true of the southern portion of the county, with notable exceptions in some cherty ridges west

68

GEOLOGY OF THE PALEOZOIC GROUP.

and north of Lime Branch (P. 0.). The elevations of the central part of the county vary from 50 to 150 feet, with only limited areas rising higher. Often high and slightly undulating lands extend for many miles. The eastern part of the county~ east of Rockmart, becomes rough and bold, amongst prominent bills of the Ordovician slates and limestones. The highest of these is Carnes' mountain, 1,291 feet. In this corner of the county, the capping of hard siliceous rocks on the disturbed glates has caused the hold character of the ridges. The same is true on other hills near Lime Branch. The more abrupt hills and ridges are otherwise generally characteristic of the cherty portions of the Knox dolomite ; whilst the more gentle undulations are principally due to the decay ofthe more calcareous Knox limestones; and the valleyf'l are mostly derived from these limestones, s~me calcareous shales of the Oostanaula, and the calcareous rocks of the Machuca series. The streams of the county are all small, except Big Cedar creek (a tributary of the Coosa riyer). Fish and Camp creeks, in the eastem part of the county, are small and flow towards the Etowah river. The streams in the valleys amongst the rugged hills are insignificant, and many flow only in damp seasons.

IN FLOYD CO U NTY.
The northwestern side of the Lower Paleozoic belt in Floyd county is approximately defined by a line drawn directly between the bend of the Coosa and the Oostanaula rivers, upon their right or northwestern side. But the margin is irregular.
From Rome southwestward, the Coosa valley forms the extensive "flatwoods," comparatively level land across which the Coosa river flows in an irregular, broad valley. This tract on the east is bounded by a low range of hills, which skirt the western side of Van's valley (from Cave Spring to near Rome).
Eastward of this belt (made of the Knox or Rome sandstone, a lower Oostananla series) is V an'H valley, from one to two miles

PHYSICAL FEATURES OF FLOYD COUNTY.

69

wide, excavated out of Oostanaula shales. This is the yaJley in

which the East Tennessee, Virginia and Georgia Railway is built.

Eastiof this last zone, there is a succession of valleys in Floyd

county-south of the Etowah river-which are largely character-

ized by narrow ridges mostly trending somewhat east of nGrth with

intersecting connections. These ridges rise from 150 to 300 feet

above the stream. This character continues to the valley of Spring

creek,~~where the features are broader in outline. Due east of

Ohulio, on the border of Bartow county, there are several high

isolated ridges.

North of the Etowah river, or of Rome, the Oostanaula, river

flows through a broad valley of shales. Upon its western side,

it is sometimes continuous with the valley composed of Carboniferous series which is brought in contact with th~ Oosianaula shales

by the "Saltville'" fault. East of the valley, there are the .crested

ridges of the siliceous members of the Lower Oostanaula series.

Upon their eastern or southeastern side, there is a great valley

which is a continuation of Van's valley (not so called), through

which runs the East Tenner-;see, Virginia and Georgia Railway.

This valley widens to about four mile~> in the northeastern corner

of the county. The southeastern -,ide of the valley is bounded by

somewhat rugged hills, which ~in the northwestern corner of the

county, at Hermitage or "Ridge Valley," rises into a ridge of 500

to (iOO feet in Armstrong's Mountain.

.

Along the Etowah river t.he country is rolling without crested

ridges, as also the higher country drained by Dyke's creek.

Spring creek flowing northward and Dyke's creek flowing south-

ward are the only important streams in the eastern part of Floyd

county.

IN YARTOW COUNTY.

Between the metamorphic hills and the Etowah river, the country is undulating without sharp crested ridges. On the border of Floyd county there are sonie high ridges.

70

GEOLOGY OF THE PALEOZOIC GROUP.

Northward of Cattersville a broad, undulating valley extends along the base of the metamorphic mountainous border to beyond the county line-with its character somewhat broken, near Pine Log Postoffice, amongst low ridges and hills, at the divide of waters flowing southward and northward.
Between this valley and the meridian, a mile or two east of Kingston, the country is variable and rolling, with broad surfaces and numerous streams, but generally with high crested ridges. But from Kingston to a point on the Gordon county line, three miles east of Adairsville, there is a chain of ridges, and the country is somewhat broken. Westward of Kingston and Adairsville the country is rugged, and in the northwestern corner of the county, near Armstrong mountain, it is quite broken. Southwest of Kingston, and southwest of Cassville the country is rugged, but with softened contours between. West of Cartersville," and back from the river, several isolated domes rise to heights of 500 feet above the Etowah valley. Between these and Cass station the valley is gently rolling.
N umerons small streams flow from the metamorphic girdle northward to the Etowah. Northward of the river about two-thirds of the eountry is drained by the streams flowing into the Etowah; the northern portion draining through Gordon count3:.
IN GORDON C'OUNTY.
The Oostanaula river flows through a continuation of the "fiatwoods," a belt composed in part of comparatively flat land, and in part of minor ridges.
The valley of that river, as well as the Coosawattee, above Resaca, is a broad, irregular plain. The Oothcalooga, Sallacoa and Pine Log creeks are the principal secondary streams, and all flow northward, through rolling valley lands. West of Lilly there are some ridges, the highest rising 150-250 feet above the drainage plains. The central portion of the county forms a gently undu-

PHYSICAL FEATURES OF :HURRAY COUNTY,

71

lating meridional belt. Farther east, the streams have moulded the features into greater undulations of bills and valleys. On the whole, the topography of the country is simple as far as the metamorphic belt at its eastern edge.
IN MURRAY COUNTY.
Between the Connasauga river and the Cohutta and other mountains, the country has a simple structure with gentle undulations. The elevations range from 750 to 850 feet above the sea. South of Dnnn postoffice there are some short ridges rising to 1,200 feet. So also north, from near Loughridge postoffice for about six miles there is a chain of crested ridges rising to from 1,000 to over 1,200 feet above the sea.
The valleys of the Connasauga river and of the principal creeks (the Holly, Mill, and Sumach) have considerable breadths. These streams have numerous tributary branches.

IN WHITFIELD COUNTY.
From the Connasauga river to the Cooahulla creek, the features -of the county are similar to those of Murray county, but somewhat more rugged. In the vicinity of the East Tennessee, Virginia and Georgia Raifway, the county is characterized by several parallel {Jhains of interrupted ridges, from 100 to 300 feet above the valleys, which are sometimes narrow and again broad and undulating. These cherty ridges form the northwestern water-shed of the Coosa drainage which flows towards the Gulf of Mexico.. Separated by valleys more or less underlaid with shales, the ridges extend throughout' the western part of \Vhitfield county; however, the hold Rocky Face ridge rises to an elevation of from 1,500 to 1,700 feet, crosses the western part of the county and forms the eastern water-shed of the East Chickamauga creek which flows through the valley about 900 feet above the sea. The western part of the county is occupiecl by "Taylor's ridge" and its parallel .spur, Dick's ridge, including some valleys within the mountains.

72

GEOLOGY OF THE PALEOZOIC GROUP.

The East Chickamauga aqd the Cooahulla creeks are the only streams of importance flowing through the county, apart from theConnasauga river upon its eastern margin.

IN CATOOSA COUNTY.
The eastern part of Catoosa county is similar to 'Vhitfield, with a continuation of the same ridges and valleys, including Taylor's ridge and its extension, beyond Ringgold, the White Oak mountains. These mountains rise into a bold, narrow ridge from 1,300 to 1,500 feet above the sea. Westward of the mountains two forks of the Chickamauga, and the Peavine creek flow through broad valleys, separated by cherty ridges rising from 100 to 300 feet.

IN CHATTOOOA COUNTY.
East of Taylor's ridge, and between it and John's 'mountain are Dirt Town and Armuchee valleys, separated by a plateau, known as Little Sand mountain. This plateau rises 300 to 500 feet above the valley, whilst John's mountain, to the east, has an elevation of' from 1,300 to 1,468 feet above the sea, or 600 to 800 above the Armuchee creek. Dirt Town valley is broad and rolling. The Armuchee creek drains to the southeastward into the. Cooiia river. John's mountain forms the eastern boundary of the county. In crossing the county, Taylor's ridge has an elevation of 1,300 to 1,400 feet above the sea. Between it and Pigeon mountain the valley is traversed by some cherty ridges rising 200 or 300 feet above the Cbattooga ri\er and tributaries. The northwestern corner of the county is represented by the plateau of Pigeon mountain rising to an elevation of 1,700 feet above the sea.
IN WALKER COUN'l'Y.
This large county presents two features-the broad valley, east of Taylor's ridge, and that of Lookout creek. These have an elevation of 800 to 90lJ feet above the sea, with a number of cherty ridges extending in a northeastward direction, rising from 100 t~

PHYSICAL FEATURES OF WALKER COUNTY.

73

250 feet above the general elevation. of the valley. One of the most prominent of these subordinate elevations is Missionary ridge. Into the county, a northeastern spur of the Lookout mountain extends, which is known as Pigeon mountain, with an elevation of from 1,800 to 2,000 feet above the sea, but with one point rising to 2,331 feet. Along the top of this mountain, the boundary of the county is located, and thus the features pass into Dade county. Lookvut mountain presents an elevated plateau from 1,800 to 2,000 feet above the sea, but with a few points rising higher. High, Point has an elevation of 2,408 feet, and Round Top, to the south, 2,378 feet above the sea. Round mountain has an elevation of over 2,200 feet. From this point, Rock creek rises and flows longitudinally along the surface of the mountain, forming one of the most picturesque features of Georgia, adjacent to Lula falls and Lula lake. McLamore's cove, between Pigeon and Lookout mountains, is nothing more than an enlargement of a similar stream to that of Rock creek, running longitudinally along the mountain. This cove is drained by the west branch of the Chickamauga creek. East of Pigeon mountain, the Yalleys are drained southward by the / Chattooga river.
IN DADE COUN'l'Y.
Lookout mountain is deeply incised by lateral valleys known as Trenton's gulf and Johnson's crook. Fox mountain is an isolated remnant of the Lookout plateau. Lookout valley is traversed by a number of ridges parallel to its sides-a similar repetition, but on a smaller scale, to the topography east of Lookout mountain Separated by the deep valley of Lookout creek (which has an altitude in Georgia of from 800 to 900 feet, is Sand mountain forming a plateau somewhat lower than Lookout, from which the principal stream flowing in Georgia is Nickajack creek. In Lookout valley,however, there are some isolated remnants of the former extended plateau.

'74

GEOLOGY OF T HE PALEOZOI C GROUP.

LA.KELETS, SINKS AND CAYER.
In the Knox dolomite country, especially connected with the gra)r lands, there are many lakelets or ponds, sinks and caves. These lakelets are simply lime sinks containing water. Sueh are of commonest occurrence east of Adairsville, and west of Cartersville. To a lesHer extent lime sinks are seen in the belt of Oostanaula .shales, but these are of small size owing to the inferior development of the underlying limestones. Lula lake, in Walker county, is simply a pothole in the cailon of the stream.
The sinks are always situated over limestone formations, arid are closely connected with the system of caves whieh traverse them, :as they are simply surface depressions occasioned by the falling of the roofs of the caverns.
Hardin's cave (lot 104, 17th district), about three miles south-east of Kingston, is one of the largest caves seen, and of g-reat extent with far reaching galleries. Some of the chambers are 20 to 25 feet high. Owing to the sloping roof the cave appears higher. The floor is covered with four to eight feet of cave dirt, overlaid by fallen blocks. It was once a source for saltpetre.
These caves are of geological interest. That in Ladd's mountain gives (see plate) some records of the date of its excavation. The mountain is now an isolated peak rising 500 to 600 feet above the hroaJ Etowah valley. The rocks dip at gentle angles, and some portions of the eaves show that its excavation was subsequent to the mountain uplifts, which disturbed the strata. But the caves, in this isolated knob, are above an elevation whete any sufficient stream capable of forming such cavities could now gather. This shows that the excavation took place before the great rock decay and atmospheric erosion had lowered the \'alley of the Etowah below the level of the dome and caves, else there had been no gathering ground for them to give rise to the subterranean stream. In :short, the excavations of the cave commenced immediately after the completion of the monntain uplifts, at the close of the Paleo-

CAVES.

75

zoic era, but their formation bas long ceased, owing to the lowering of the general level 9f the country by denudation.
At Cave Spring, near Nannie, Woodlands, and numerous other places, extensive caverns also occur iri the limestone formations.
In northwestern Georgia, beyond the Coosa basin, caverns are oc<Jasionally met with in both the Knox arid Chickamauga limestones. Crawfish Springs, at Chickamauga, is amougst the most interesting, as a large strea~, sufficient for utilization as a water power, issues from an underground cavern and is now converted into a beautiful lake and waterfall. Many caverns, some of which are extensive, occur in the Mountain Limestone at the bases of Lookout, Pigeon and Sand mountains.

76

GEOLOGY OF THE PALEOZOIC GROUP.

ALTITUDES OF RAILWAY STATIONS IN NORTHWESTERN GEORGIA.*

FEET ABOVE SEA LEVEL.

Esom Hill ........................ 927 East and West Railway of Alabama.

Berry...... . . . . . ... . . .... . .... 853 ''

"

"

"

Cedartown..... . . ............... 767

"

1 '

Rockmart .... :.. . . .... . . . .... . . 741 "

"

Taylorsville . . . . . . . . . ..... . ...... 721 'I

. r

CartersvUle . . . . . . . . . . . . . . . . . . . . . . 750 "

"

"

"

Alabama State Line . . . . . . . . . . . . 930 East Tenn., Va. and Ga. Railway.

Pryor's. . . . . . . . . . . . . . . . . . . . . . . . . 844 "

"

"

"

Cave Spring .. ................... 697 Van's VT"alley ..................... 662

''

,,

lJ

Cunningham .... . .. .. ..... . ..... 707 "

''

Rome .................. . ..... 652

"

"

Reeves . . . . . . . . . . . . . . . . . . . . . . . . . 658 ''

"

"

Dalton . . . . . . . . . . . . . . . . . . . ..... 782

'

"

Seney. . . . . . . . . . . . . . . . . . . . . . . . . . 830 "

"

"

"

Rockmart . . . . . . . . . . . . . . . . . . . . . . . . 762 "

"

"

"

Cass . . . . . . . . ..... , . . . . . . . . 765 Western and Atlantic Rail way.

Kingston . . . . . . . . . . . . . . . . . . . . . 710 " "

"

"

Adairsville . . . . . . . . . . . . . . . . . . . . 710 '' ''

''

Calhoun ............ . . . ......... 657 " "

"

Oostanaula river is 32 feet below

plains.

Resaca..... . . . . . . . . . .

654

Tilton ...................... . .. ... 665

Dalton . . . .......... .. .......... 775

"

"

"

"

"

Tunnel Hill . . . . . . . . . . . . . . . . . . . 853 Ringgold . . . . . . . . . . . . . . . . . . . . . . . . 785

"

"

Gordon Spring

............ 965 " ''

"

Villanow ...... . .. . .............. 914 " "

"

"

Holland . . . . . . . . . . . . . . . . . . . . . . 783 Along Central Railroad .

Summerville . . . . .... , . . . . . . . 780 '

"

"

Lafayette .. : . . . . . . . . . . . .

871

''

"." Chickamauga . . . . . .

750 ''

''

Cassandra . . . . .

. ........... 982 In McLamore's Cove.

Rising Fawn . . . . . . . . . . . . . . . . . . . . 797 Along Alabama Great Southern:R'y.

Trenton . . . . . . . . . . . . . . . . . . . . . . . . 739 "

"

"

Wildwood ...... . .............. . . 742 "

"

Cole City . . . . . . . . . . . . ........... 1354 On Sand Mountain.

"

Round Mountain Station .......... 1810 On Lookout Mountain.

''' Corrected from Gannett's Dictionary of Altitudes, and Mr. McCutchins' Report to:Hon. J. T. Henderson.

GEOLOGY OF POLK COUNTY.

77

CHAPTER X.
LOCAL GEOLOGY OF POLK COUNTY.
CONTENTS. CHILHOWIE AND 00STANAULA SERIES. KNox DoLOMITE SERIES.
CHICKAMAUGA SERIE8: Maclurea Limestone; Deaton Ore Beds; Rockmart Slate RED MouNTAIN SERIEs. Sun-cARBONIFERous SERIEs.
CHILHOWIE AND OOSTANAULA SERIES.
Only a very small area in the northwestern corner of Polk county is occupied by Cambrian rocks; and this is very much broken by great faults.
The valley in which the East Tennessee, Virginia and Georgia Railway is constructed, between Tecumseh and Cave Spring, is mostly excavated out of Oostanaula shales. Parallel with the railway, and close upon its eastern side, the shales are sharply bounded with the decayed rocks in the ridges of Knox dolomite. The characteristic rocks are blue shales dipping about 20 in direction S. 40 E. But at the surface they are drab or variegated, and broken up into fine shingle owing to their decay and disintegration. The calcareous matter is removed from the shales, and out of them, the valley is mostly formed. Below the depth of disintegration the shales show semi-metamorphic texture and fotm slates. Upon the western side of the valley the shales rise in subordinate ridges, often eovered with thin suil.
Beyond these subordinate ridges, Indian mountain rises to 1,100 feet above the valley. In the lower portion, thick beds of quartzitic sandstone occur intercalated with shales, similar to those de-

78

GEOLOGY OF '.rHE PALEOZOIC GROUP.

scribed. Higher up, the crest of the mountain is covered by great massive quartzites, or crystalline sandstones. These beds dip at from 40 to 50 towards S. 30u E. Between the mountain mass and the valley shales, a great fault is situated, with the probable remains of a fold, in which the Oostanaula series appears on one side; and the Chilhowie, or Lower Cambrian, on the other, in the form of the local lenticular mountain mass, like rocks referred to the Weisner quartzites of Alabama.
Fromthe Alabama line, for some three miles, the fault brings into contact only different beds of the Oostanaula series, but farther north, the Indian mountain fault brings the Knox dolomite against a wedge of the Cambrian deposits just described. The importance of the faults is most strongly marked in connection with the next formation-the Knox dolomite. The thickness of the shales, exclusive of th e mountain mass, may be placed at 2,000 feet; and of the mountain quartzite series, probably at 2,000 feet more.
Economically, the quartzites are of value. Some of the iron ores in the eastern side of the valley appear to rest upon the shales, but probably belong to the overlying series. Below the depth of si1rface-rock decay, some of the slates on the western side of the Etna valley may prove of value.
The agricultural features of these Cambrian deposits are varied. Indian mountain is rough and broken. The valley of Etna and northward present choice farms. On the ridges, calcareous matter is leached out, and the soil is thin. But this area of Cambrian shales is small, and does not form a type of the series as seen elsewhere.

THE KNOX DOLOMITE SERIES.
This is the mor;t important series in the belt of country surveyed. As will be seen by the map, it covers a large area.
Its features are however variable. It is the formation in which the great deposits of brown iron ores, beauxite, manganese, .white

GEOLOGY OF POLK COUNTY.

79

clay, some building stones and lime, occur, and on which many of the best farms are located. Accessible at the surface, there are but! few deposits of limestone in the county. The lower beds are the more calcareous, and give rise to the most valuable brown ore deposits, and best valley lands,-most commonly red. The upper beds cont.aiu the greater quantity of siliceous matter and originate the gray ridges covered with cherty gravel. The dip of the eock is often difficult of determination, as their decayed. remains do not generally show stratification. Still, in some artificial cuts, lamiuations are exposed. (See plate II.) The less disturbed portions of the Knox dolomite begin with the fault, just eaet of the Tennessee, Virginia and Georgia Railwayt where ridges rise 200 or 300 feet above the valley. The western side of this chain of ridges is marked by subordinate rounded ridges, covered with red residual soil, and often rich brown ore deposits, which are described in the Economic Report. At this fault line the Knox dolomite beds have been dislocated by compound faulting, which has caused the beds to move upon others of the same formation, near "Hematite" siding, but upon both sides wedges of the Oostanaula series have been left. The general effect has been to leave a basin of Knox dolomite, in part ore bearing,. to the westward and northwestward of the shales, and.to bring up the quartzites of Indian mountain in topographically a high position. The fault-producing movements have come from different directions, and made a remarkable deformation of structure: On the State line some artificial cuts in iron mines reach a depth of 60 or 70 feet, with the original rock decayed, and leaving only residual clay, etc., with iron ore. Some of these ferruginated masses occur in beds four or five feet thick, dipping as much as 40 both to the northeast and, north west, showing great disturbances and breaking up of the strata, not merely as if by dislocation, but if as in part by the strata falling into caverns on the removal of the calcareous matter feom the original limestone.

.80

GEOLOGY OF THE PALEOZOIC GROUP.

In a rail way cut at Oredell, the ilecayed strata, showing great disturbance, consists of white clay or other rock debris at each end of the section, with intermediate deposits of confused strata, some holding iron ore. The chert is now scattered through the mass in a manner almost as heterogeneous as nMthern drift. These beds dip at variable angles and in direction about north 15 west. Near by the ore accumulations rest beneath a white clay 10 to 15 feet thick. On adjacent ridges there are cherty beds more or less ferruginous. On some of the subordinate ridges all structure is lost, and only accumulations of residual clays and ore deposits are found. whilst the more cherty rock comes to the surface in many of the Tidges,. yet the valley is deeply underlaid by decayed rock, which is .ore-bearing, in an artesian well, to a depth of 180 feet.
The Knox basin west of Hematite siding is marked by ridges and valhys. Some of these ridgeE are characterized by heavy beds Df ferruginous cherty rock, and, in some cuts, show remainA of stratification. The valleys, which are fertile between the cherty ridges, form the subordinate part of this belt of country.
Northwest of Cedartown, the basin of Cedar creek and its tributaries form a rolling country with red fertile soil, but away from it, in the northwestern corner of the county, the ridges are of cherty gray soil. . The cherty limestones on the border of Floyd county, south of Cave Spring, dip at only 10 to the east. Some of the ridges contain iron ore and manganese. Near Cave Spring, the subordinate ridges in the valleys are ore-bearing.
On the road from Cedartown to the crossing of Cedar creek, the red clays predominate. But beyond this point, in crossing the ridges, gray lands occur.
West of Cedartown, for three miles, on the road to Pryor, the reel
of rolling lands predominate. Near this point, a ledge (three feet)
cherty rock occurs. Beyond no bed rock is seen. The red ridges and ore lands in Etna valley are noted elsewhere.
The same road crosses ore bearing ridges before reaching the

GEOLOGY OF POLK COUNTY.

81

grayer land. In the large ore workings in this vicinity, occasional glimpses of the structure have been exposed. In one place, a ledge of the ferruginous rock was seen passing under white clay (Peek's Bank) on the hillside; near by is a bluff of ferruginous siliceous rock, much jointed with seams resembling stratification; apparently the dip is 45 E. S. E.
The country between the limestones (Ordovician) extending southwestward from Cedartown and the State line, near Esom Hill, is underlaid mostly by the Knox series, similar to the country to the west of Cedartown, but with few of the more crested and cherty ridges, and with many red lands and ore beds.
Between Cedartown and the Fish creek region, near Grady, the Knox dolomite mostly forms a high rolling gray or cherty country. But its western side, adjoining the valley of Cedar creek is characteristically red soil, with subordinate ridges of iron ores, containing more or less white clays (see cut illustrating clay "horses"). The position of the strata may be seen west of Young's Mills, where some masses of ferruginous rock occur with bedded structure, dipping eastward at high angles.
l.J t t h no rth L'Jl entral pur of tb co untry, along t h water f t h - n rbh bn uw b of edar creek ttn d mo. tly b twe J.l ' mdy and : n y h r i a lwoad ttret\ f J"d land wi'tb s me or e deposi .
F1o ~ w 'at. 1 rad.\r to lwlf a mile casb o:f ~ is h r <> l (P. .)
.he r d bml pr vai_l.; in t h va lley of F i II creel< ~l nd a lon g t he jn rlotion f t,he "Kon x. 3(> 1omi_te bed' o.nd the snooeedin g li m. on . R tw >n Fitsh ree k n.ncl R ook rnat , the o tmtry l om po eJ f rolli tlg low h el'ty l'idges. All f b elts t.ten.d northea<ot ward.
Across the northern part of the county the Knox dolomite has au un br oken wid th of ov r i;o,: .een 111 \l - w ith eXJ I.\U i, n reacl1i ng m I' t h:111 tw nty mil . Tit r ok , where in dica ting h clip, are ul wuy: at co nsidemble a ng les, wlti c h wonltl rep1e ' Il Lau i 11 o1l eiva ble d velopmenl , \\P r t h , apr a nt t bi kn ... not redneed b r un dul utio n.J, fold s o~ fn nlt~. A the rooks ar so .e ld 11'1 -.xp . ~ ~
(6)

82

GEOLOGY OF '!'HE PALEOZOIC GROUP.

showing the position of the beds, the occmrence of the undulation

might be doubted. But as some indications are found in the decayed

rocks and in the overlying Maclurea limestones and Rockmart slates,

the evidence is conclusive that these are not merely undulations, but folds with occasional overthrows more or less affecting the underlying strata. Again, the occnrrence of the lower beds of the Knox series is seen in the decayed red soils and ore beds, in some

half dozen principal parallel belts which are more or less charac-

terized as valleys separated by subordinate ridges.

The relation of the valleys to the rocks, has, in a large measure, been cleoided by the greater solubility of the calcareous beds of the inferior portion of the formation, and the protection rendered ttJ the higher heels by thin mantles of residual chert. Thus it is thatduring the long erosion, which has left from 100 to 200 feet of re-

1-iidual clay derived from the decay of 1,000 or 2,000 feet of the im-

pure limestones-the valleys, subordinate ridges (often also resulting from protection of iron ores) and red lands are characteristic of the lower portion' of the Knox dolomite series, which is repeatedly brought to the surface by undulation of the strata. Some of

the crested ridges are probably in part, at least,. due to .folds and

overthrows and in some cases to minor faults.

The residual Knox clays do not retain water, and wells are only

obtained at the considerable depths of commonly from 60 to 100

feet.

. .

Some characteristics of the Knox dolomite are better developed in other countries, and the occurrence of the mes are given in the

Economic Report.

CHICKAMAUGA SERIES.
MACLUREA LIMESTOXES.
About Cedartown and resting in a basin of the Knox series, there occurs the Maclurea limestone, which is often somewhat impure, especially in lower beds. The limestones are found in beds

GEOLOGY OF POLK COUNTY.

83'

with somewhat indistinct stratification, and again, in thin but com-:pact beds. The rocks in this county are somewhat rnetamorphic-
lin:i to ne. Tbes weatheJ' i nt round d surfaces and m valley
mnlrin " Consequently :hey are usttally clo ely l' latcd to tll valley f t he Ku :x doJ ornite erie . B ut tb e. p l ed belt'S are mos ly nan w. Th . oil is Ll. ually mo.re or less heavy red clay. Tll'i. formation occurs about Cedartown and is well exposed along the streams. It is also cavernous and often gives rise to large springs (as at Cedartown).
Bordering the slates of Fish creek region, the limestones com e' to the surface and are best shown along the various creeks.
In the Rockmart district the series, underlying beautiful valley lands, forms an extensive wing to the northwest of the slates.
The rocks frequently lie at low angles; at Blue Springs, Cedartown, the dip is 5 to 10 in direction N. 20 W. About a mile to the south, at Tanyard Branch, there is an anticlinal where the rocks dip upon their eastern side 10 or less, in directionS. 70 to 80 E., whilst upon the western side they dip 45 decreasing, to 15 in direction N. 80 W. At a mill about two miles south of the town the rocks dip 70,0 S. 80 E. These dips correlated with others in the succeeding shales indicating folding, which will be noted in the paragraph on Rockmart slates.
About Rockmart, the limestones are commonly at comparatively low angles. In the railway cut east of Devitte lime quarry the limestones dip at about 20 S. 40 to 50 E., and lie unconformably beneath slate hills.
The Maclnrea limestones and their analyses are noted in con- nection with their Economic phase.

DEA.TON ORE BEDS.
These rocks seem to be identical with Safford's Iron-limestone series. They are only known at interrupted points for several miles northeast of Rockmart. T~ey are thin bedded, ferruginous

84

GEOLOGY OF THE PALEOZOIC GROUP.

limestones. In some places the rock is so decayed as to leave only laminations of ocherous earth, or this again is charged with more or less shingle of iron ore. Other beds are compact, dark gray limestone. At the Deaton mine, the beds formed the roof of a cavern
.excavated in Maclurea limestones. (See plate r., frontispiece.) At
!the pit of Central Mining Company, four miles northeast of Rockmart, the represented ore series. is on a small anticlinal, restiing over Maclurea limestone which trends northeastward.

ROCKMART SLATE.

These rocks are semi-metamorphic slates and overlie the Maclurea

limestone, occupying three basins, upper part of Cedar creek, Fish

creek and Rockmart district. In the Cedar creek basin, the surface

rocks are everywhere decayed; when not discolored in decaying the

slates are blue; but usually the weathered shingle is drab or some-

times red.

The shales commonly lie at comparatiyely low angles in the

Cedar creek basin.
How v 1, at th C. U.. c r . -Rail way tati< u in dar town, t h :y dip 8f>0 i.n dit , ti u . 80 E ., whil..J. 0 f et be oml (ea. twn.rd) ue

dip i. qnJ y 4:)0 ;o .

0

'o mbining t his trllctltt'e wi th th

lir noted

i u th E:\ ~bclnr a lim to u s, we itud t hat t.h rc is a fo ld uucllooal

overthrow passing along a line just east of Cedartown, with the axis about S. 10 W.
Owing to this folding, the underlyin g Knox dolomite is brought up to the surface in two or three subordinate ridges south of Cedartown.
W'hilst the strata are seen to dip nearly eastward, ~yet the easte!'!: border of the basin is defined by the Knox dolomite, owing to the undulations and foldings of th e rocks; to which are evidently du e the metamorphism that has hardened the shales and somewhat cn."tallized th e limestones.
The southern border of the Rockmart s1ates is defined uy ti1e

GEOLOGY OF POLK COUNTY,

85

Cartersville fault, beyond which Dug Down mountain is composed of hydromica schists.
In ' this basin, the slates are more or less valley making, but underlie some chert (Lower Carbon.iferous) deposits. The characters of the Fish creek basin are similar to those of the Cedar creek slaty basin. They extend around to that of Rockmart. At Hightower Mills, the hydromica schists of Dug Down mountain abut against the slates, and.dip 45 S. 80 E., the trend of the fault not being that of the strike of the rock beds.
Five or six mil~s to the eastward, at Simpson's Mills, the Rockmart slates are at very high angles, whilst the overlying hydromica schists of Dug Down mountain overlie the former (owing to the Cartersville fault) at. only from 20 to 25, in direction S. 30 to 50 E.
The Rockmart series, in the Rockmart district, form bold ridges, some of which are covered with cherty deposits (Lower Carboniferous).
In the slate quarries, at Rockmart, the beds are more or less. jointed, but dip at 45, and more southeastward. In the railway cut, east of Devitte's lime kiln, the slates dip 25-30 in direction S. 50 E.
In some places, the decay does not reach more th"an a few feet into the slates. In weathering, the surface sometimes becomes bluish, but generally yellowish gray, or fi!.Ore rarely yellowish brown, being covered at several points; the lower slates weather into a thin soil, and into the banded and indurated clay known locally as "Caen stone," susceptible of being turned and polished (see Economic Report).
In the Rockmart district, the slate ridges form a rough country, but to some extent the rolling valleys are a slate formation .
. Conglomerates occur at about two miles south of Rockmart, in a ridge on the road to Simpson's Mills. They consist of irregular mas:'les of slate and quartz, cemented into hard rocks, reaching

GEOLOGY OF THE P ALEOZOIC GROUP.
nearly 200 feet in thickness, and dipping 60 or 70 S. 40 E. The rocks are underlaid and succeeded by the slates. At this point the disturbances have been great. These constitute a lower member of the Chickamauga series.
The slates are elsewhere considered in their economic bearing.
RED MOUNTAIN SERIES.
Overlying the Rockmart slates, at a point four miles southeast of Esom Hill, near the foot of Dug Down mountain, there occur thick beds of massive quartzitic sandstones, fOVering only a small area. These may be referred provisionally to the Red Mountain .series. Similar sandstones in some of the ridges beneath the SubCarboniferous chert belong to this horizon.
LOWER OR SU BCARBONil'EROUS SERIES.
Overlying the slates of the Rockmart series, there are several Tidges covered with blocks and fragments of chert south of Cedar,town, between Young's and E som Hill. Again, the cherts on the ridges in the Rockmart district belong to the same horizon, and may be referred to the Fort Payne chert. In places, the chert forms a bed pf sandstone, which is ferruginous in part (as on Mr. vVest's fa;m); and also Iiear Rockmart. The preservation of the Tidges, as also those of the Rockmart district, are due to the protection given by the flinty beds and cherty gravels.
MODERN DEPOSITS.
"Except the conti~ued action of the weathering of the older rocks, the creeping down the hillsides of decomposed material, and the occasional deposits in swampy ground (which are rare), no modern formations can be considered as occurring in the country, for the streams are not flowing through such lands as would permit of bottom formations; still th ere are a few places where streams overflow the basins through which they pass."

GEOLOGY OF FLOYD COUNTY.

87

CHAPTER XI.

LOCAL GEOLOGY OF FLOYD COUNTY.

CONTENTS.
OosTANAULA SHALEs. KNox DoLOMITE. RED MouNTAIN. Sun-CARBONIFEROUS: Fort Payne Chert; Floyd Shales ; Coal Measures. LAFAYETTE(?) AND MODERN.

OOSTANAULA SERIES IN COOSA VALLEY WEST OF THE OOSTANAULA FAULT.

The rocks of this formation are mostly reddish, greenish or varie-

gated, calcareous shales, forming gray or brownish soil or reddish

farther north. However, there are thin beds of earthy and siliceous

limestones, and in the upper portion, the limestones are more mas-

.sive, and veined with white calcit()s.

On the Georgia and Alabama line, this series covers a country

:about ten miles wide. It dwindles down to a narrow belt at Rome.

But northeastward it broadens out into a belt one or two miles

wide. On the southeastward side, the outline is somewhat regular

:as is marked by the topographic features in the more sandy ridges

(Knox or Rome sandstone), or lowest portion of the Cambrian sys-

tem exposed. Owing to the remarkable fi:mlting on the north-

western side, there are two marked troughs nearly surrounded

by the Lower 'Jarboniferous series.



This belt occupies a comparatively level region, from 120 to 150

feet above the river, and forms the "flatwoods" country. Some

points rise higher and the hills are capped in some places by cherty

gravel (remains of overlying patches of Knox cherts). North of

Rome, ridges are more characteristic of this belt than south of that

88

GEOLOGY OF '.rHE PALEOZOIC GROUP.

point. But, as a whole, the country presents no very prominent features. The soil has lost most of its calcareous matter and is often poor, but again, it appears of fair value.
The most notable limestones form a surface of about 200 feet in width, and is situated at a short distance from hills along the Oostanaula :l!wlt. These limestones are dark colored and earthy, but mottled with numerous veins of white calcite. This limestone forms a characteristic bed. About half a mile northeast of Thomas' Mills, it dips 45 S. 40 to 50 E. At a roadside quarry, about half 1J. mile southwest of Thomas' (on Kirk's Groove road) the bed dips 25 N., 20 E., and just beyond the dip is again S. E.
Again, one mile west of Cunningham station, it is a notable feature. About three mile southwest of Rome, a bluff of the mottled earthy limestone rises 30 or 40 feet above the river. The limestones also occur in the northeastern corner of the county.
The shales dip at variable angles. Near the Alabama line (one mile north of Lnmpkin'~-J store) the shales dip 50 S. 20 E., whilst at a point near the line, but two miles from the border of the series, there is a narrow belt of shaly limestone dipping 75 S. 10 E. These variations, as well as many foldings, seen in overlying horizons from Rome to Cave Spring, show very great disturbances and numerous foldings. Southeast of Livingston therE' is a belt of shaly limestones which are somewhat fossiliferous.
Upon approaching Livingston, the soil changes from a residual deposit to a recent series-probably the Lafayette series-which will be noted later.
N~rth of the Coosa river the faulted character of the northern border of the series is striking. One long, narrow tongue, forming an anticlinal belt of shale, has been carried westward of the great overthrust fault and there preserved, whilst similar strata, once lodged upon Horseleg mountains, have been removed by denudation.

GEOLOGY OF FLOYD COUNTY.

89

OOSTANAULA SERIE::3 EASTWARD OF THE FAULT.
The ridges of hills which bound the southeastern side of the "flatwood" belong to the lower division of the Oostanaula series, and have been called Knox or Rome sandstone. Still the shales, often calcareous, predominate in this lower member. The sandstones form thin beds amongst the shales and are very rarely in thick layers. The sandstones are more or less earthy, and when the thin beds are broken up angular or subcubical fragments result and then lie scattered oyer the often yellowish soil. One of the best sections seen is where Big Cedar creek cuts across the formation, some three or four miles northeast of Cave Spring, near Connor's Mills. On the stream just named the earthy sandstones are shown, and dip 30 S. 60 E., resting on dark shale. In a ravine, near by is "Slide Rock" at the same dip. It is a quartzitic bedded sandstone with a drab colored surface, but bluish in the interior. This is the most massive bed of sandstone seen, being two feet thick. It is succeeded by other but more earthy and thinner sandstones. This slide rock has its surface highly polished, as if glaciated ; but the !'moothed surface passes beneath other rock and is a case of slickensides, due to internal movements of the rocks. Just beyond, near the ford of the creek, on road to Thomas' Mills, the sandstone members are exposed.
In the vicinity of'Rome, the different members of the Oostanaula series are very much disturbed and broken by faults, many of which are seen in sections where road cuttings, etc., have been made. In the northern suhnrb, there is much dark shale amongst the saudstone. The shales dip 45 S. 60 E. northeastward, the crested ridges are interrupted, and are usually of no great height. The soil is often of yellowish color, or, again, reddish. These sandstone members of the series do not cover more than from half of one to two miles in width (except locally), and are known where best developed by their ridges being covered with angular blocks of sandstone, and are confined to the zone west of the shale-formed valleys,

:90

GEOLOGY OF. THE PALEOZOIC GROUP.

through which the East Tennessee, Virginia and Georgia Railway extends. The ridges often dwindle to insignificant features.
The variegated calcareous shales of the higher members of the Oostanaula series are characterized by zones of impure bedded limestones, often in thin layers with earthy partings. Its topographic feature is valley making, covering a belt from one to two and a half miles (in the northeastern part of the county) wide, and giving rise to fine farming lands. But the shales themselves may form subordinate ridges. Owing to faulting, a spur extends into Polk .county; but the valley passing northwarfl to Cave Spring continues northward under the name "Van's" valley and extends to Rome.
At Cave Spring the series is folded and dislocated, as seen in a :Section on the hills west of the town as shown in figure 9, p. 20.
Some of the shales are siliceous, of dark color and indurated. Disturbances almost equal .to those of the "flatwoods" are shown in the shales on the ridge between Cave Spring and Thomas' Mills.
In many places the limestones appear in the valleys. Thus, at Connor's Mills, and Little Cedar creek, about three miles northeast ()f Cave Spring, thin bedded limestones (some two feet thick) are developed in the shales to a thickness of about 50 feet. Here the dip is 30 S. 30 E. At various places in Van's valley, limestones are exposed along the branches. . Just west of Cunningham station, in the valley, borings have been made, and these limestones with a dark brown color were found to be more than 90 feet thick. They dip at low angles of less than 10 towards the southeast. About a mile and a half northeast of Cunningham, about 25 feet of these same limestones are again exposed in a railway cut, dipping at low .angles.
Jnst south of Rome the shale series present more hilly characteristics and are particularly disturbed and dip at various angles up from -!0 to 60,:and in variable directions approaching S. 60 E. In everal road cuts the beds are much faulted by small throws in different directions. At this place, in some brown shales, thel'e is a

GEOLOGY OF FLOYD COUNTY.

91

fault hading 20 to southward, whilst the beds dip at about 40. A qua-rter of a mile farther south (at end of a hill) there is another fault hadi!Jg 60 to northwest. These differences show complex movements and distortion. At a quarry just south of Rome, along roadside the disturbed shales dip 50 to 60 S. 60 E.
Along the Etowah river, just above Rome the dist_urbances of the .strata' are well shown. At the waterworks heavy limestone beds were struck at thirty feet. This is in part a flinty limestone and in part a compact dolomite rock, resembling some beds of the Knox dolomite, but in position near the junction of the calcareous and the siliceous beds of the shale series. The rock is much fissured by subterranean drainage. Fossils are not preserved, but the lithological character suggests a fault or overthrow, bringing Knox dolomite into the horizon of the well without its appearance at the surface. The thickness of the rock is more than 60 feet. Just above the waterworks, sections of the shales and limestones are shown. Impure limestonE-s, in beds from one-half to two feet thick, occur in the mottled shales, some of which have the appearance of hydromica. These dip 30 S. 65 E. Some of these limestones are dark blue, fine grained, of crystalline texture, having a thickness of 100 feet or more. A few hundred feet higher up the river, where E. T., V. & G. Railway crosses the Rome I-tailway, there is a fold and overthrow, the axis of which trends N. 30 E. The rocks are very much crushed but where not too much distorted show vertical jointing in direction S. 65 E. and N. 45 E. There is not only folding but also faulting.
Owing to the great disturbances and dislocations the true structure about Rome is somewhat difficult to recognize. A spur of the upper part of the series runs from Rome up the valley of Silver creek, and at several points the limestone beds are seen. Amongst the Knox ridges between Silver creek and Cunningham, there are ~everal spurs of the shale series. Northeastward from Rome the ~hale bearing valley widens out somewhat and forms an excellent

92

GEOLOGY OF THE PALEOZOIC GROUP.

agricultural district. Wherever the streams cut across the shales the included limestones appear in their valleys.
References to the economic phases and the soils are made elsewhere in this report.

K~OX DOLOMITE SERIES.
West of Cave Spring there is a narrow basin of this series~ brought into position by faults already referred to in Polk county. Otherwise the series covers only the comity southeast of the valley already described, or most of the country southeast of the East Tennessee, Virginia and Georgia Railway (Alabama branch).
South of the Etowah river, the western part of the Knox dolomite country is characterized by ridges of the gray cherty lands, with red, loamy intervening valleys. The broadest of the Knox valleys are those of Silver creek and Spring creek, and outside of them the country is rather broken. Between these streams there is a belt of the red Knox lands, as also east of the latter creek. However, all the ridges are not of gray cherty land but most of those of the more abrupt configuration. In many of the valleys there are subordinate ridges of brown ore. In some of the less abrupt ridges and gray land country there are beauxite beds.
In various regions, especially in the vicinity of Cave Spring~ manganese ores occur. In many localities, on the ridge and along some of the streams, the dolomite or magnesian rock is exposed in an undecayed condition showing the character of the formation. From the economic standpoint these characters are noted elewhere. The dolomite, as shown in the ridge east of Cave Spring, is a dadr colored, more or less Parthy, siliceous rock weathering to a lighter shade. It is massive, often with indistinct hedding. The dip is 30 S. 70 E. In this ridge there is one of the largest caves in Floyd county and through it a large stream flows, whence the name of the town, _Cave Spring.
Overlying the Cambrian shales already described, the lower

GEOLOGY OF FLOYD COUNTY.

93

beds of limestones are well exposed about a mile east of Cunningham station, in a ridge rising over 400 feet in height. For nearly 300 feet of this elevation, the rock is seen, but the upper part of the ridge is covered with a mantle of stony soil and cherty gravel, but fertile soil. The limestones are dolomitic, somewhat earthy, and of dark color, but mottled with white calcite. The bedding is massive, and dips 10 southeastward.
A mile and a half east of the last, and at the northern end ot
the next ridge, on the land of Mr. Gibbons, there is a rock similar to the last mentioned, but of darker color forming a bold outcrop. It is peculiar in containing more or less angular fragments of breccia of impure dolomite, derived from older masses. But the whole is conso1idated. These rocks have been quarried to some extent for a dark marble, noticed elsewhere (Egyptian quarry).
On the spur of Armstrong mountain, near Hermitage (Ridge Valley), the mountain rests upon Cambrian shales, and above them, 200 feet or more of the limestones are seen. The beds vary from one to eight feet thick, dipping less than 10 S. 60 E. Locally, some beds dip southwest (pl'obably the results of a lime sink). Some of the lower beds are dark limestones, with crystalline facet.s; others are mottled with clayey matter. The upper rocks are of compact dolomite of light color. This chain of ridges continues through the northeastern corner of the county, and east of 'Nannie dips at 20 S. 60 E.
All of these deposits are from beds belonging to near the base of the Knox series, or perhaps some of the beds may be of Cambrian age, as in Tennessee, although lithologically connected with the Ordovician system. But so far, fossils have not settled the horizon.
On various ridges, the undecayed rocks occur near the surface, and also in the side of the valleys, as for instance, the thin bedded magnesian limestone!'! along the streams on the Home road, from HounsaYille, about four miles from the former place. The siliceous beds of the Knox dolomites are also often seen, and sometimes

94

GEOLOGY OF THE PALEOZOIC GROUP.

these are ferruginous, as for example, just east of New Prospect church, about six mileo northward from Cave Spring. Other siliceous limestones decaying into gray soil, occur near the manganese deposits of Major ,J. M. Couper on border of Polk county,

and of Mr. Stokes, also on border of county, near C. R. & C. Ry,

In Bartow county, however, some characteristics are bett8r exposed

than in Floyd county, and will be noticed hereafter, and in that

county will be found the descript,i"on of the section shown at Dike's

creek in Floyd county.



The Knox dolomite is usually decayed to a great depth, except on the higher ridges, the product being various forms of calcareous clayey land, and on the ridges often a cherty arenaceous soil. As the result of decomposition, great deposits of white kaolin of various degrees of purity are often seen. These beds contain much

undecomposed feldspar, are commonly more or less associated with

the iron ore, and were probably deposited in lenticular masses.

Sometimes they arise from the cherty dolomites, in which case the

white clays are chatged with cherty fragments, as at Cave Spring. West of the E. T., V. & G. Ry. (Atlanta division), the country

consists of narrow ridges and valleys, and many beds of brown ore, manganese and also beauxite occur. In the southeastern corner of the county, the valleys are broader, with frequently the red soils and iron ore beds. The same remarks are true for the Knox formation of the county north of the Etowah river.

The greater dislocation and repetition of the ridges of the Knox

series occnr adjacent on the northwestern border of the formation, and consequently the greatest change of features and resourcesgiven in detail elsewhere.

RED MOt:NTAIN SERIES.
Southwest of Rome, the Red Mountain series occurs on part of Ho,seleg mountain, forming a sharp ridge, capped with heavy Randstones. This ridge is a remnant of an anticlinal elevation, with the

GEOLOGY OF FLOYD COUNTY,

95

sandstones preserved in places, so as to make the surface appear

like a monoclinal ridge. Another small outlying ridge occurs

farther west-Judy mountain. When disintegrated, the sandstones

produce cubical or rectangular blocks, which become scattered over

the surface of the ground.

.

Lavender mountain (with the highest point 1,683 feet above tide) is a spur composed of the Red Mountain series. The southern end of the ridge is badly dislocated and folded. In the cut of the Central Railway, the average dip of the shales is 25 S. 60 E. for the

eastern portion; proceeding northwestward, the dip increases to 45 , beyond which the shales dip 60 to the northwest; but at a short distance, west of a ravine, the beds again dip southeastward at 30. ln part, t.he beds are much jointed with fmcture seams

trending S. 80 E., and dip 60 to 70. In part, the rocks are heavy bedded shales, often calcareous, but weather to red, sandy shales. There are some flags of red sandstone from six to twelve

inches thick, intercalated with shales. Some heavy bedded quartzitic sandstones also occur in the series. The whole formation is from 800 to 1,200 feet thick.

Near the northern end of the ridge, tbe strata, upon the eastern f!ide, dips 20 S. 60 E. But in the mountain, the dip increases to 60 in the same direction. Upon the western flank of the ridge, the Fort Payne chert occurs. This indicates the anticlinal charac-

ter of the mountain, but with the axis west of the summit, thus producing the superficial appearance of a monoclinal ridge. The rocks are shales, shaly sandstones, and some sandstones in beds two

feet thick.

John's mountain and a spur of Taylor's ridge form the boundary

of the county, but they will be considered in the geology of Chat-

tooga county.

96

GEOLOGY OF THE PALEOZOIC GROUP.

SUB-CARBONIFEROUS.
FORT PAYNE CHERT.
At the surface, the Fort Payne chert is characterized by cherty soil. This is shown upon the flanks of the ridges bounding Texas valley; also upon the west side of, and at the northern end of Horseleg mountain, and upon the southern end of Horn's mountain. In a few sections only are the cherty limestones exposed, as in Horn's mountain and on flanks of Lavender mountain, in belts too narrow to be shown upon the map.

FLOYD SHALE.
The seri8s (named by Hayes) is best developed in this county, and in position lies above the Fort Payne cherts, and below the Mountain Limestones, which only occnr beneath Rocky mountain. The rocks are composed of yell0w, brown and black shales, often in heavy beds, calcareous shales and shaly limestones, and occasional beds of pure limestone. Some of the limestones and calcareous beds are very fossiliferous, as west of Rome, nPar the lime kiln, and at other places.
Near Rome, the rock is a dark blue shaly limestone, in thick beds, and dips at 10 S. 60 E.; whilst elsewhere, the dip is 20 to 30. But in crossing the formation, the variation of the dip, sometimes S. E., and again N. WT., shows great foldings and probably faultings, so that the true thickness of the formation cannot be estimated with any degree of accuracy.
This formation gives tise to a portion of the "flatwoods," with yellowish and dark grayish soils. Some sandstones occur as local features in the series, and give rise to low ridges in Texas and Dirt Town valleys.
COAL MEAS URES.
A remnaut of the lower portion of the Coal MeasUl'es occurs on an outlying ridge in Floyd county, called Rocky mountain_ Its greatest geological interest is its position of fifteen miles east of the

GEOLOGY OF FLOYD COUNTY.

97

most eastern plateau of the Coal Measures. It is an index to the great amount of erosion, which has removed the Coal Measures from Georgia. (See question of erosion under Chattooga county.)
Rocky mountain is represented by eighty feet of massive sandtones a n l on lomel'att~ i ~:; in g in ver tiunl wn.tls, espcci::tlly n_p n tll w tern side of the ridge. Below th sand b ne Lhe undetl yiug tra:tu me oucealed fo1 250 ot 3 0 fe t but t;hey are probably (l0ffi1 os.ed of shal s. :Dhe s~m dt3tones dip 20 . 0 E.

LAFAYETTE (?) SERIES, AND MODERN DEPOSITS,
The loams and gravels above the greater streams in this belt of Georgia are provisionally correlated with the Lafayette formation of southern Georgia. Objections to the introduction of endless local names led to the use of this nomenclature, as their valley deposits probably belong in that series.
These deposits are extensive, and occur even as far as a mile or two back (rarely three miles) from the greater streams, and reaeh elevations ro higher than in keeping with a depression, when the o euni level f tlte wat ts allowed th ncc nm nlations of th . Lafay-
t te rmin ~ts f~:~t n rth as olnrubus, with. -ptobahle embaym nts uorthward. li'J' ut tb ypical L!tf~tyettc se ries in that la ti.tud , thcr i:-- no fu,rt,her d.i fferen e in IP c.hal'Mt l' f tlr - e dep s.i ts i.u Eloy l cou.nty than betw n . bore accnmu.laiious and those Jorm d in exteoai.v . ba.y J: channels from t wo t:o fout miles in wioth, su h us ex isted ul ng the lower pnr f t.he valley, when son tbe rn
l'gia wn 7.00 OL' 80 fee below the present alti-tude, whic!t IJtought he s tt far in land.
These Lafayette accumulations are usually red clayey loams, and coarse, well water worn gravel, up to four or even six inches long. It is mostly quartz, bnt occasionally with some local Paleozoic calcareous and fossiliferous stones. The deposits seldom reach a thickness of twenty feet, but commonly eight or ten, of which the gravel may be from two to five feet thick, or again wanting. The gravel
(7)

98

GEOLOGY OF THE PALEOZOIC GROUP.

underlies and to some extent graduates into the loam. A few places may be taken as typical representatives.
Livingston is on a plain about a mile from the river, with the sandy soil derivcd from the Lafayette deposits. Underneath, the gravel rises to 100 feet above the river terrace, which is about 20 feet above the ordinary water-line.
On the north side of the Coosa river, near Coosaville, these gravels rise 140 feet above the river, or about 780 feet above tide.
On the hills about Rome, the same deposits occur up to from 140 to 150 feet above the river, or about 790 feet above tide.
V.lest of Nannie, and opposite the foot of Turkey mountain, the gravels rise again to 140 feet above the river (the Oostanaula), or something less than 800 feet above the sea.
There are frequent remains of terraces at 100 feet above the rivers, but these are imperfectly preserved. The principal terrace, often half a mile or more wide, is commonly between twenty and thirty feet above ordinary water, and is liable to floods.
'Vhilst the measurements are only aneroid, yet from the large number of observations, it may be said that the Lafayette deposits rose to the height of 140 feet above the rivers in Floyd county, and are now principally found, not in the valleys but on the hills ; for since their accumulation enormous erosion has broken their continuity, and there remain only fragments of the former great sheet, as it has been mostly swept away, by denudation, just the same as has the Lafayette series in parts of southern Georgia.
Agriculturally, these deposits give rise to variety in the distribution of the soils. The Lafayette soils are often liable to be mistaken for red Knox dolomite soil~.

GEOLOGY OF BARTOW COUNTY.

99

CHAPTER XII.
LOCAL GEOLOGY OF BARTOW COUNTY.
CON1'ENTS.
OosTANAULA SERIES. KNox DoLOMITE SERIES. CHICKAMAUGA SERIES. LAFAYETTE (?) SERIES. MoDERN SERIES. MouNDs.
OOSTANAULA SERIES.
Exposed along Tom creek, about Woodlands, the valley through this broken country shows a narrow belt of these shales, forming an anticlinal basin, in which the limestone members are seen Upon its western side the limestones dip 40 N. 60 vV.; upon its eastern side the shales dip at variable angles, S. 70 W.
At Kingston there is a small area of the shales. Northward a narrow belt of the series a few hundred yards wide extends to Cement. This is an anticlinal where the western strata dip 10 N. 70 W. In passing from the Connesenna valley, the belt broadens in the valley of Oothcalooga creek to a width of about three miles in region of Adairsville.
At the southern end of the basin, the limestones (forming hydraulic rock at Cement) form a prominent low ridge. (See plate XI. in Economic part of report.)
The rocks are more or less impure limestones, with earth seamings, so that they may weather into thin banded laqJ.inations, which are commonly characteristic of some of the beds of the limestones of this series. The series at Cement is exposed ic the workings,

100

GEOLOGY OF THE PALEOZOIC GROUP.

so that measurements can be made. The section in descending shows:
Blue limestone ___ ________ _ , ____ - -- - - 8 feet Slaty limestone (cement rock) _______________ 4 " Blue limestone _____ _, ________________ __ _ 6 "
Argillaceous earthy limestone _____ . __ __ __ 2 " Siliceous limestone (hydraulic rock) .- ____ _ 4 " Siliceous limestone (cement rock) ____ __ ___ 7 " Fine black limestone _____ ___ __ _________ l~ "
Earthy limestone ____ ------ ___ -------- _ 3 " Shale___________ .. .. ___ . __ _ - -

The analysis of the cement rock is given in the Eeonomic Report.
It is highly siliceous limestone, with alumina and iron. Some of the beds are composed of limestone with interlacing seams of earthy matter, giving a peculiar netted appearance, which is often characteristic of the limestones of the series.
At many points in_ this belt of Cambrian deposits, the limestones reappear and form a ridge or little escarpment like that at Cement and east of Adairsville. This valley in the Oostanaula series forms a very fertile belt.
The rocks dip at low angles, and form an anticlinal valley belt, in which there are caverns and lime sinks.
Southwest of Cartersville a tongue of the shale series has been brought to the surface by undulations of the strata. In places it contains limestone beds. Along the branch a mile westward of the town, the shale is indurated to a hard semi-metamorphic slate of dark color. Along the road to Ladd's mountain the decayed shales are sometimes blue : but the weathered shales are generally reddish, although of lighter color than the soils resulting from the Knox dolomite. Along the road just mentioned, about a mile from Cartersville, the beds dip to south of west; half a mile be-

GEOLOGY OF BARTOW COUNTY.

101

yond, undulations of the strata are seen in the beds, which immediately underlie the residual Knox dolomite clays. Here they contain thin calcareous beds.

FrouRE 18.-Junction of Oostanaula shale and overlying residual Knox dolomite earths.
In the section (figure 18) decayed Knox dolomite succeeds an anticlinal of Oostanaula shale.
To the east of this exposure the clays are mottled red and bluish, and in composition are like the non-calcareous metamorphic schists of the neighboring mountains. (See Economic Report upon the clays.)
Along the Tennessee road, shales frequently occur, and about three miles north of Cartersville (at Dr. Felton's) an impure limestone (forming a light colored impure marble) is seen along a branch (on east side of road) dipping southeastward. Although the rock is metamorphosed and crystalline it belongs to the shale series.
Along Petty's creek, about four miles from Cartersville, the limestones of the shale series are exposed, and dip 70 S. 80 E. The valley along this creek is undulating and fertile. At the low divide between it and Sallacoa creek, the country is somewhat more broken. Here a dome resembling a northern drumlin in outline (about 60 feet high and 400 feet in diameter) is seen. Beyond, the softened features are renewed, and at Boliver (crossing of Pine Log creek) the limestones appear at the surface, and are penetrated with caverns, out of which large springs flow, The rocks of the overlying metamorphic series are decayed,. and the hydromica schists often weather to a bluish color, and sometimes occur in the edge of the valley.

102

GEOLOGY OF' THE PALEOZOIC GROUP.

Just beyond the county line, at Erwin, the limestones lie beneath metamorphic schists, which have been forced over them.
At Roger's (old) furnace the limestone occurs in the valley, and near by is brown ore apparently resting upon it. .
At Cassville the shales have more or less calcareous seams; in some cases they are indurated and resemble hydromica slates and Knox dolomite.
Most of Cedar creek and its branches flow through the shale country; and the limestones of the series are commonly exposed by the streams, showing the dip at from 10 to 15 S. 60 W. on Cedar creek and its branches.
Along little Pine Log creek and other branches the limestonet> rise through the shales. In this Cambrian series, in northeast Bartow, the shales rise into flattened ridges covered with indifferent land. But adjacent to the streams, and on the lower grounds, the agricultural features greatly improve. The calcareous shale formation, especially along its borders, is characterized by extensive fertile valleys.
One or two small outlying patches of the shales rise through the overlying dolomite, as for example, three miles southwest of Cass statioi1.

KNOX DOLOMITE SERIES.
The characters of the middle and upper beds of the Knox dolomite are somewhat better shown in Bartow county than in Polk and Floyd counties.
Along the Rome railway, the ends of several spurs have been cut into. The charactetistics ~een here extend into Floyd county, but the sections along the rail way are here noticed as a unit.
From Dyke's creek, to east of Wooley's ferry (three miles west of Kingston), there are several sections from which the following observations were obtained: ,Just east of Dyke's creek, the bluffs exposed in the railway cut rise 25 or :35 ft!et ; the surface of the

GEOLOGY OF BARTOW COUNTY.

103

limestone is imperfectly rounded, and much more rugged than the limestone of the Maclurea series, or of the underlying Cambrian beds. The bedding is well defined, in layers from three to five feet, although these often become broken up or else end abruptly, owing to small faults. These fault lines, or joints, in many cases, are f:'lvorable to rock decay, and hence, seams of clay are often seen filling crevices fotmed by weathering. The texture of the rocks is sometimes semi-crystalline, as in the case of the lighter colored purer dolomites; but commonly, it is earthy or siliceous. The surface often weathers to dark colors, but the decay does not usually penetrate deeply into purer rock. All degrees of impurities are seen in the various strata. At places, gteat beds are made up of impure, laminated, calcareous beds, one or two inches thick, which are so earthy that they weather into siliceous, shale-like beds.
In the purer rocks, which are more durable, occasional layers of dark flint (like in chalk beds) one or two inches thick occur. In other cases, the flint predominates in beds one, two or more feet in thickness. St1ch beds have given rise to the sheets of vesicular chert often occurring on the ridges. Again, the chert is disseminated in irregular concretions through the dolomite, and as the calcareous matter is dissolved away from such exposed beds, the clay, sandy matter and flints are left. The finer matter, being washed off by rai us and rills, finally leaves the ridges covered with mantles of cherty gravel, with some larger blocks. Many of the flints are more or less translucent in the beds, but those left upon the surface, after the rock decays, are white or staine!) with iron.
At the mouth of a small stream, ou the border of Bartow and Floyd counties, at a railway cut, a bluff of residual earth, left from rock decay, rises 60 feet high.
On both sides of Wooley's ferry, there are fine exposures of the undecayed rock, rising in the blnfls, out of the yellowish

104

GEOLOGY OF THE PALEOZOIC GROUP.

residual clay. The structure of the rock is shown in plate II., opposite page 42. Repetition of strata as shown in figure 16.
As shown in plate, the bedding is often indistinct, but with lines of flinty concretions. The hard dolomite rocks rise up out of the residual clay in a remarkable manner, especially well shown as in plate III., page 43 (south of Dalton).
These masses of decayed rock are too great to have originated only along joint lines, and there seems no reason why portions of the beds shouH have remained solid, whilst other portions of the same horizon should show decay for the whole height of the exposed bluff.c; (30 or 40 feet). It is probably due to minor faults bringing some of the more durable rocks into contact with some of the less permanent. The solid rocks appear more frequently upon the eastern side of the deeply decayed masses. Occasionally, the residual clay shows bedding, but this is generally quite obliterated.
The dip of the rocks at Dike's creek is less than 10 S. 60 E. Locally the dip was seen to be also S. W. aud N. E. West of Wooley's ferry the dip varies from nearly level to 15 N. 60 W. A short distance beyond this exposure the strata dip to S. E., showing a low anticlinal. In short the whole breadth of the formation is one of repeated undulations. Some sandy layers are included in the formation; and Alg::e were found near the county line.
Ladd's mountain, three miles southwest of Cartersville, is an isolated inass, but may be taken as a type of the dolomite ridges. (Plate IV., opposite.) It rises about 500 feet high, with a northern and southern wend. Its face has been uncovered for quarry purposes. The rock is a siliceous, hard and somewhat brittle dolomite, from light to dark in color, but all fine grained, compact and crystalline. The layers are tl,ick. The bedding is disturbed, and in places appears as if the rocks had fallen into cavities, which may have been the case. The dip is 10 S. 80 W., and owing to form of exposure and undulations, the direction cannot be accurately de-

GEOLOGY OF BARTOW COUNTY.

105

termined; but probably a little south of west. There are joints of 50 feet or more in depth, which have been opened by decay and filled with clay. These commonly trend east and west, and are 20 to 00 feet or more apart. There are other joints with directions northeast and southwest, and again others at right angles.
This mountain is pierced with caves, some of which are vertical channels. These have been formed by streams dissolving out the limestone after uplift of strata, but before denudation of the valley, as already pointed out. The caves contain large and beautiful stalactites.
About two miles west of Ladd's mountaii1, there is another similar isolated 'ridge about 500 feet high, the top of which is covered with chert; but ravines on western side show hard, crystalline dolomite. These beds dip 20 S. 60 E. Accordingly, the intervening valley is synclinal. Other similar ridges occur farther west.
At Hardin's (Saltpetre) Cave (lot 104, district 17) about three miles southward of Kingston, the dolomite is exposed in a ridge. The beds dip 20 N. 70 W. The rock is dark colored and of fine grained texture. The cave descends to a depth of about 80 feet, and the chambers are of large size, with numerous ramifications and many chambers. There are very few stalactites. (See article on caves.)
At Kington (or Aikins') lime quarry, two miles east of Kingston, the solid rock is again seen. The decomposed covering '\'aries in depth to a remarkable degree, as before described (figure 1, page 10). The rock is darkgray dolomite with bands of black flint or chert.
Along Two Rock Run creek, south of Kingston, dolomite is exposed in a ridge. Hence to the Etowah (at Hardin's Ferry) the country is composed of low gray hills, which also appear above the river for a short distance upon the south side, beyond which to west of Ligon Postoffice, the red and iron-bearing ridges prevail

106

GEOLOGY OF THE PALEOZOIC GROUP.

(trending east and west), or rather a succession of hills and valleys, like a billowy sea.
On a farm of T. F. Nichols, a well in process of excavation showed the red earth to a depth of 30 feet, below which the residual clay becomes light colored but not cherty. (Depth of well is more than 60 feet.)
South of the Etowah, and along Euharlee creek, much of the country is rolling, without abrupt ridges, and with red and grayish red soil, and some ore deposits derived from the less cherty series of the Knox dolomite. Along the river, and for a mile or two back, upon the hills, the Lafayette accumulations cover the residual clays, in many places to an altitude of 90 feet (obse~ved).
North of the Etowah river and west of Cartersville, the Knox series has produced a rolling country with some isolated rocky
1
ridges. Southwest of Cass station, the cherty ridges are more prominent. Northeast of Cass station there are two spurs with iron ore deposits, forming basins over. the Cambrian shales. North of the Etowah river the formation is undulating, and even the gray lands are less rugged.
Between Tom's creek and the Connesenna creek, the country is occupied by both ridges and rolling red lands, in some places iron bearing. Between Adairsville and Armstrong mountain, the country is often rugged and cherty, but with some iron bearing hills.
The belt of country between the Cambrain shales east of the western.& Atlantic railway, and the south fork of Two Run creek and Cedar creek is formed out of Knox dolomite. Upon the western side of this elevated region there are. prominent ridges, but elsewhere there is a somewhat more softened topography with rolling plains, which are often cherty. At Mr. Combs's, east of Adairsville, the Knox series dip 20 northwest. Adjacent to the streams, there are broader depressions, and in several localities iron bearing and red lands, derived from the lower portion of the formation, are seen.

GEOLOGY OF BARTOW COUNTY.

107

CHICKAMAUGA sr;:RIES.
Near Taylorsville, the Chickamauga limestone just enters the county; and two miles north of this village a small basin is seen.
LAFAYETTE (?) SERIES.
Along the Etowah river, the loams and rounded gravels occur upon the hills to a height of 90 feet. However, the greater portion has beP.n removed by subsequent denudation. The gravel is often coarse, and composed of well rounded :quartz.
Along some of the smaller streams, as the upper waters of Pine Log creek (vicinity of Pine Log .Postoffice), :Coarse water-worn pebbles of sandstone and conglomerate occur. These are of local origin, derived from the metamorphic rock in the mountains to the east.
MODERN DEP03ITS.
To a limited extent only do river deposits occur. Along the Etowah river they are hardly more than twenty or twenty-five feet above ordinary water. Generally the other streams do not. give rise to extensive bottom lands. For these bottom clays, see Economic Report on Clays.
Deposits containing fmgments of small bones are found in Hardin (Saltpetre) Cave, near Kiugston. These accumul~tions are from four to six feet deep, and are more or less covered with fallen blocks. The emth has been used in manufacture of.saltpetre.
MOUNDS.
ThrQe miles north of Cartersville, there ara three prehistoric mounds (known as the Tumlin mounds). The largest of these covers about three acres, and is built up to a height of 40 feet, with steep sides but a flat top. The two smaller mounds seem to have been protective, and are situated just above and below the great mound, and between it and the river. They do not cover more than half an acre each, and rise about twelve feet above the plain. Some at"chreological remains are said to have been obtained from these mounds.

108

GEOLOGY OF THE PALEOZOIC GROUP.

CHAPTER XIII.
LOCAL GEOLOGY OF GORDON COUNTY.
CONTENTS. OosT~~AULA SERIES. KNOX SERIES. RED MouNT-AIN SERIES. CHATTANOOGA BLACK SHALE SERIES. SuB-CARBONIFERous SERIES: Fort Payne Chert and Floyd Shales. LAFAYETTE AND MODERN SERIES.
FAULT.
OOSTANAULA SERIES.
Across the western portion of Gordon county, there is a belt of shale defined upon the western side by the Sackville fault, which brings the Cambrian system into contact, often without topographical breaks, with the Carboniferous rocks which, in part, are com-
1) ed of dark heavy shal s, an ] in part Jf t1e 1emai;u f Ler y lime t n . . Th t'O lc 11 r e 1111 re t' le. s variegated shales, hut r rl bing le and li ~h t red nnd yellowish soil are pt yul nt. Th re i also a modetutc d v h11ment f th 111. ttl d e~uth y lim e:tou s so
characteristic of the formation in a similar position farther south. In this section of country the shale series constitutes gently undulating plains with low ridges. The western belt in this vicinity is more cultivated than it is in the "flatwoods" southwest of Rome, and has generally a more fertile appearance than farther south, with growth of timber like that on the neighboring rich lands to the east.
In a field in the trough, north of Turkey mountain, the contact of red Cambrian shales and the brown Carboniferous shales

GEOLOGY OF GORDON COUNTY,

109

is strongly marked-the actual contact being represented by crushed shales of a few feet thickness.
The shales of the river region are flanked on the eastern side by the lower beds of the river, brought up by a fault. These have occasional thin seams of decayed yellowish sandstone which form interrupted ridges. In the region of Resaca, the anticlinal structure of the basin in the southern part of the county still continues. At that point the limestones dip 15 N. 60 W.
In some cases, as west of Resaca, the shales are of darker color, but commonly the belt of those deposits closely resemble those of a higher horizon in the series. The timber on these ridges is the same as elsewhere on the Oostanaula series-short-leaf pine, red and spani'5h oak, a few sycamore and hickory, some chestnut, and black jack on some of the poorer ridges; but the lands do not generally indicate sterility.
Most of the country, as shown upon the map, is underlaid by the shale formation.
The valley of the Oothcalooga is the most fertile, with deep red soil and the limestone beds exposed in t_he valley. In the formation, there are occasional limestone sinks. Eastward of the Knox lands, the Cambrian formations are more or less broken with the red shingly beds predominating. These, where not weathered, are often of dark color. Along the streams the limestones are exposed. The surface soils are thin upon the upper ridges; but in the valleys, especially of the Sallacoa, and along the foot of the metamorphic mountains, to the east, they are of good quality. An anticlinal basin, projecting westward upon the Bartow-Gordon line, is composed of dark red shale lands, bounded by the ridges of the Knox dolomite series, dipping at low angles.
K:!I'OX SERIES.
Northwest of Adairsville there are small areas of the Knox series, in which the more rugged features of Bartow county become softened to a gently undulating country.



110

GE OLOGY OF THE PALEOZOIC GROUP .

To the east of the Oothcalooga basin the ridges continue from Bartow northward along the western part of the Knox basin, but diminish in height. Elsewhere in this basin there is a gently undulating country, composed of gray land. A small basin east of Calhoun has the same softened character.

RED MOUNTAIN SERIES.
In the northwestern corner of the county, Horn's mountain rises into a prominent ridge 800 or 900 feet high. West of Sugar Valley the ridge is capped by shales and sandstones of the Red Mountain series, the strata dipping southeastward. Upon the eastern flank, there is a characteristic red soil, but the "fossil ore" beds are wanting, as the formation scarcely reaches that horizon.
CHATTANOOGA BLACK SHALES.
Upon the eastern side of Horn's mountain, the deposits of the last series are succeeded by the black shales of the Devonian system, which are well shown at the old iron ore pits northwest of Sugar Valley. The accumulations do not exceed 20 feet in thickness.

SUB-CARBONIFEROt'S SERIES.
The Fort Payne chert occurs ou the southern end of Horn's mount~in, and also above the Devonian shales upon the ea<;tern side of the mountain, fart.her northward, and contains brown iron ore. In !the valley east of the mountain the Floyd shales, with their flaggy brown or red weathered shales, are seen. These form a strong contrast with the weathered red shales of the Oostanaula series to the east, which are thrust over the eastern edge of the Floyd shales.
THE LAFAYETTE AND MODERN SERIES.
On the hills and for a distance of two miles, the red surface deposits of loam and of quartz gra.vels are seen up to an elevation of 80 feet. Distant from the rivers they are not seen and this elevation



GEOLOGY OF GORDON COUNTY.

111

is as great as the country near the greater streams attains. The characters are the same as in Floyd county.
The valleys oi the Coosawattee and Connassauga rivers, and of some of the larger creeks are wide, but defined by irregular hills. These .plains are from fifteen to twenty-five feet above the ordinary stages of water and are liable to be flooded.
IFAUL'l'.
As the Oostanaula shales belong to the Middle Cambrian horizon, an enormous fault becomes apparent. This fault is equivalent to a vertical throw amounting to from 7,000 to 10,000 feet. However, upon examination, this dislocation is found to be an overthrust fault, whereby the older formations to the east have been pushed over the Carboniferous formations for a distance of four miles and a half, this measurement being obtained from the occurrence of an area of Sub-Carboniferous strata, which rises through the capping of the overthrust Oostanaula shales. The outcrops just referred to are situated west of Resaca, and have been exposed, owing to denudation, removing the overthrust strata from this area.

112

GEOLOGY OF THE PALEOZOIC GROUP,

CHAPTER XIV.
LOCAL GEOLOGY OF MURRAY COUNTY.
CONTENTS. 00STANAULA SERIES. KNOX SERIES. CHICKAMAUGA SERIES. RED MouNTAIN SERIES. LAFAYETTE AND MODERN.
OOSTANAULA SERrES.
Between the Connasauga river and the foot of the Cohutta mountains, the Oostanaula shales cover the whole southern part of the county, as also along. the river and along Holly creek valley. The greater part of this region is made up of the red and variegated shales, which are often dark where not decayed. These deposits weather into shingle, covered by thin soil, where they form ridges. The limestone of the series frequently appears along the streams. A long the Connasauga river, Holly creek and other valleys, at the foot of the metamorphic mountains, shale containing more calcareous rocks form fertile valleys. The characteristics are simply an extension of those of Gordon county. The beds frequently show a great amount of internal folding and mmor faulting.
KNOX SERIES.
Overlying the last series, there is an elongated basin of the Knox dolomite. It is usually'an undulating country composed of fprtile red lands-both hills and valleys-in its southern and central portions (as about Spring Place).
Further north there are some rolling gray lands. At several places magnesian limestones of the Knox dolomite series are exten-

GEOLOGY OF MURRAY COUNTY.

113

sively exposed in ridges, as on the property of Captain Tilton, and others west of Spring Place. (Se1! Economic Report.)
As the Oostanaula shales and limestones often underlie the metamorphic rocks at the foot of the Cohutta mountain range, so along Sumack creek, the Knox dolomite passes under the metamorphic zone to the east.
CHICKAMAUGA SERIES.
Succeeding the Knox dolomtt ael'ies thete i a narrow belt occupied by higher slates, etc. But betwo~u them and the Knox series there are various beds of t he g r:ay li rue&tune, exposed in the valleys as near Loughridge on the E'a tern side, and as east ot Cohutta Springs P. 0.
Overlying the limestones, there is a bed of variegated and brown shales, with occasional calcareous seams. The rocks are not metamorphic. These shales dip at moderate angles to the east-southeast. North of Loughridge they rise iu ridges of considerable height, which, however, owe their preservation to a capping of Red Mountain sandstone. Between the ridges and the mountains, there is a broad, fertile valley modified by the disintegration of the sandstones overlying the shales. The metamorphic strata of Cohutta mountains are seen overthrust upon a portion of the Chickamauga series.
RED MOUNTAIN SERIES.
Capping the crested ridges of the Chickamauga series, there is a. consolidated fine grained sandstone, occurring in thick beds which aggregate about 200 feet. It is these rocks which give rise to the crested ridges. The rock is fine grained and consolidated into a light colored quartzitic structure. These rocks are probably identical with Safford's Clinch mountain series or one of the variations of the Red Mountain ser!es, as on Rocky Face.
LAFAYETTE (?) AND MODERN SERIES.
At various points above the Connasauga, the red loam and
(8)

114

GEOJ.OGY OF THE PALEOZOIC GROUP.

quartz gravel of the Lafayette (?) rises to about 80 feet above the .rivers.
'The flood ,plf!.,in~:~ of the Counasapga a.re not so ,hJgh above this Jl"iver as further'south, and only rise 15 to 20 feet above the ordinary .stages of the waters.

GEOJ,OGY OF WHITFIELD COUNTY.

115

CHAPTER XV.
LOCAL GEOLOGY OF WHITFIELD COUNTY.
CONTENTS.
OosTANAULA SERIES. KNOX SERIES. CHICKA~1AUGA SERIES. RED MouNTAIN SERIES. SuB-CARBONIFERous SERIEs. LAFAYETTE AND RII:CENT SERIES.
OOST A.'S AULA SERIES.
The Oostanaula shales present the same features as in other counties, being divisible into shingly beds (upon its eastern ridges), fertile anticlinical valleys and the low ridges with thin sandstone layers at the western area. (In this location, the grounds for lithological distinction into the Knox sandstone and Knox shales, obtain more forcibly than at any points to the scwth.)
In the valley of the Connasauga river and Cooahulla creek, the characters are identical with those of Murray county. In the western part of the county the Oostaoaula shales are repeated by faulting, making four belts (see figure 19 and map). Such is the narrow fertile valley in which th~ E. T., V. & G. Ry. is built from
Dalton oo the Tennessee line. From Cove City, northward, there
is another such valley between great faults. This shale valley is pinched out west of Varnell, but again continues to the northward
Another fertile shale valley, is that in which Tunnel Hill (P. 0.) is situated, but its western side is. succeeded by a ridge of the lower beds with sandstone (or Knox sandstone). This belt widens out eastward of Gordon Spring.

116

GEOLOGY OF 'l'HE PALEOZOIC GROUP.

KNOX SERIES.
An elongated basin of the Knox dolomite occurs between th~ Connasauga and Coahnlla creeks. It is an undulating country o:n> e:l m H~l y of gray lands. At Cedar Ridge another small basin occur:;. Here the dolomite limestones are preserved and to some extent quarried. Some of the beds are earthy, and other;.; contain dark flint nodules.
East of the valley of Varnell (station) there is another trough with a character similar to the last-rolling gray lands with so me nherty ridges. It is, in part, succeeded by higher rocks. W e8t of Varnell there are two belts, in part, brought together by a fault. These belts are somewhat characterized by interrupted ridges, bnt they are largely gray lands forming a rolling valley.
West of Tunnel Hill another chain of interrupted ridges extends northward. Some of these ridges appear to be ore-bearing.

CHICKAMAUGA SERIES.
A belt of these Silurian rocks succeeds the Knox serief! in the northeastern part of the county. The limestones are seen in so me of the valleys. The upper beds are brown and variegated calca-
reous shales which, in part, give rise to deep red soils. Some or
these beds are highly ferruginous (see Economic report); others are siliceous. The limestones sometimes occur in thick beds. It is probable that the iron ore beds represented in this county belong to the Deaton sub-series.
The Dalton basin is made up of Chickamauga shales. Owiug to the limitation of limestones, and some sandstones, a chain of crested hills extePds northward from Dalton. These latter sandstones may be remnants of the Red Mountain series.
Between Dalton and Tunnel Hill there is a trough of the Chickamauga formation, with brown shales predominating, but intercalated with limestones and sandy shales. These deposits extend through the gap of Rocky Face mountain, west of which there is a

GEOLOGY OF WHITFIELD COUNTY.

117

long narrow trough of valley lauds. The Chickamauga rocks extend upward into the mountain side.
RED MOl'N'l'AIN SERIES.
Rocky Face or Chattoogata mountain forms a chain extending from near Tunnel Hill southward. This chain is dislocated into parallel but discontinuous zigzag ridges to Horn's mountain and is composed of the Red Mountain series with the different riclgelets connecterl by rocks of the same formation. The ridge rises up into a bold mountain from 1,500 to 1,791 feet above tide. It is capped with a quartzitic sandstone lying in heavy beds, dipping 25 N . .80 E. at the gap in the ridge north of the road. At Dug Gap, a few miles to the south, the strata dip 45 S. 80 E. Whilst there are some shales upon the eastern flank, from the summit of the mountain downward upon the western side, the section shows heavy bedded gray quartzitic sandstone, 20 feet; laminated sandstone in thick beds, 40 feet; red sandstones in thick layers with shaly partings, 40 feet; brown and red compact shale, with seams of sandstone, 200 feet; laminated shales weathering red, 200 feet. Below this elevation such shales as are exposed appear to belong to the Chickamauga series. The deposits represented in the mountain appear to rise to but do not include the "fossil ore" beds. Higher shaly beds occur on the east side of the ridge. Part of Dick's and Taylor's ridges are on the western border of this county; but they will be described in the other <:ounties.
CHA l''l'ANOOG A BLACK SHALE.
The black shales overlying the last formation and described in Gordon county, extend northward upon the eastern flank of Horn',; mountain into \.Yhitfield county.
SUBCARBO.NIFEROUS SERIES.
LTpon the eastern side of the mountain just described, the Sub-

118

GEOLOGY OF THE PALEOZOIC GROUP.

Carboniferous cherts and shales from Gordon comity extend into Whitfield county.
FAULTS.
No county in northwestern Georgia has the strata so much repeated into striking features, owing to dislocations and subsequent erosions, as Whitfield county.

FIGURE 19.-Hepetition of formations owing to faults and folds between Rocky Face and Cohutta mountains. F, Faults; K, Knox dolomite; m, Oostanaula shales.
RECENT FORMATIONS.
The most notable deposits are the gravels and loams upon the western side of the Connasauga river, similar in position to thm;e upon the eastern side of the river in Murray county.

GEOLOGY OF CATOOSA COUNTY.

119

CHAPTER XVI.
LOCAL GEOLOGY OF CATOOSA COUNTY.
CONI'ENL'S.
OosTANAULA SERIES. KNOX SERIES. CHICKAMAUGA SERIES. RED MOUNTAIN S:WRIES. CHATTANOOGA BLACK SHALES. SuB-CARBONIFERous SERIES.
OOSTANAULA SERIES.
The Oostanaula shales cross this county m two belts, one ot
which, however, is divided by a spur of Knox dolomite brought to the surface by a fault. These belts form rolling valley landR, the more eastern of which, however, is traversed by ridges, owing to the presence of some sandstones which appear in the lower part of the series, and known as the Knox sandstones in Tennessee. This belt is brought into contact with various formations all the way from the Chickamauga to the Sub-Carboniferous series, owing to an exte.nsive fault. The western belt of this series occurs along Peavine creek, which is an anticlinal valley, with the strata often dipping at high angles, bringing to the surface flaggy limestones and shales, which are probably the remains of impure calcareous rocks. Some beds of limestones are also seen.
KNOX DOLOMITE SERIES.
From Tunnel Hill northward there is a chain of ridges of this formation, forming light-colored cherty ridges and gray rolling lands. Some of these ridges show the occurrence of brown ore,

120

GEOLOGY OF THE PALEOZOIC GROUP.

manganese, etc. Across the center of the county there are two ()ther belts of Knox dolomite, sometimes rising as much as 300 feet above the undulating valley lands. These are situated on either side of Peavine valley. In the northwestern corner of the county, the rolling gray lands in front of Missionary ridge are also composed of Knox dolomite. Generally speaking the soils along these three belts are gray lands, or sometimes thinly coated with cherty gravel, which material often thickly covers the ridges. Occasionally red lands are seen. The three western belts extend southward into Walker county.
The South Chickamauga creek cuts through the central ridge and exposes the undecayed Knox dolomite. At Grayville the extensive linie quarries have brought to view the character of the rock for a depth of nearly one hundred feet. The strata dip 40 S. 60 E. The beds are very massive and weakly marked by occasional lines of bedding. The stratification, however, is indicated by bands of coloring produced by impurities. The common thiclmeHs of the strata is from bix to eight feet. Some layers have flinty seams through them. This steep inclination, however, does not recur everywhere throughout the belt. The limestones are rather dark gray in color. The residual earth upon the surface does not usually extend to a depth of more than from two to fifteen feeL, and is composed of the material after the removal of the calcareous matter from the dolomite.

CHICKAMAUGA SERIES.
Two belts of this formation cross the county. The eastern zone is the valley of South Chickamauga creek; it occurs along the western side of Taylor's ridge and White Oak mountain. Whilst this valley is composed of fertile red land, yet the limestone beds, or those interbedded with sandy shale-a residuum of decayed calcareous rocks-come to the surface at low angles, dipping into the mountains at 10 or less to the S. 70 E.

GEOLOGY OF CATOOSA COUNTY,

121

Along the West Chickamauga creek this formation constitutes a broad belt of fertile lands, through which the rocks rise to the surface in the anticlinal valley. These rocks, dipping at low _angles, produce extensive outcrops, and the roads over them are characterized by great roughness; but the material is at hand for making the best roads in the State.

RED MOUNTAIN SERIES.
Taylor's ridge terminates at Ringgold, to the north of which White Oak mountain commences and extends into Tennessee, thus forming one continuous chain, interrupted, however, by the passage -of South Chickamauga creek. This ridge is narrow, and rises to an elevation of somewhat over 1,300 feet above the sea, or from 400 to 600 feet above the valley. The lower portion of the ridge is composed of the Chickamauga series, but the upper portion consists of shales with heavy sandstones, which cap the ridge; these :are often quartzitic in texture. The formation of the mountain top reache<J to the fossil ore beds, some remnants of which are found in Taylor's ridge, which are best developed south of this county. In the northern part of 'Vhite Oak mountain, the beds dip at 10 S. 70 E. Taylo.r's ridge, in the southern part of the county, becomes synclinal, and encloses a basin of Sub-Carboniferous rocks. 'The eastern rim of this basin rises into a continuation of Dick's ridge, which is abruptly cut off by a fault upon the eastern side, bringing Cambrian rocks into contact with the Hed Mountain senes.
CHATTANOOGA BLACK SHALES.
Overlying this last formation there are a few feet of black Devonian shales, which underlie the Sub-Carboniferous series in the basins to the east of Taylor's ridge, noticed in next paragraph.

122

GEOLOGY OF THE PALEOZOIC GROUP.

SUB-CARBONIFEROUS SERIES-

This series occurs in a synclinal trough upon the eastern side of

Taylor's ridge proper. It is composed of some shaly rocks and



characterist.ic cherty limestones of the Sub-Carboniferous series.

North of Ringgold. gap this belt is rugged and broken into hills.

and valleys.

GEOLOGY OF CHATTOOGA COUNTY.
CHAPTER XVII.
LOCAL GEOLOGY OF CHATTOOGA COUNTY.
CONTENTS. OosTANAULA Sl!:RIES. K.NOX SERIES. CHICKAMAUGA SERIES. RED MouNTAIN SERIES. CHATTANOOGA BLACK SHALl!:S. SuB-CARBONIFERous SERIES. COAL MEASlTRES.
OOSTANAULA SERIES.
Chattooga river, throughout nearly its length, flows through a v.alley composed of Oostanaula shales with occasional beds of limestone. Upon the western side, the formation abuts against higher formafions owing to a fault. To the westward of this belt, another fault has brought to view a narrow basin of these shales. At Holland, there is a small anticlinal valley of the same formation. Farther northwest, in front of Pigeon mountain, another anticlinal valley begins and extends into ~Walker county. This is the most western belt of the Cambrian shales, and forms an elongated valley with the streams flowing longitudinally through it. These valleys contain fertile, red, calcareous, shaly land.
KNOX DOLOMITE SERIES.
This formation is repeated in three or four belts, according to its position in the county. Along the western side of Taylor's ridge, but separated from it by a valley, this formation is characterized by a chain of hills and rolling valley lands, the former being covered

124

GEOLOGY OF THE PALEOZOIC GROUP.

with cherty gravel, and rising 200 or 300 feet above the valleys, and the latter covered with gray dolomitic lands. W est.ofthe Chat.tooga river, similar ridges and rolling lands constitute another belt. ln places, iron ore occurs, as also bea11xite and white clays, as west .of Summerville. West of Dirt Seller mountain, there is a similar 1repetition of rolling lands and ridges belonging to this series.

CHICKAMAUGA SERIES.
Along the western side of Taylor's ridge, there is a narrow belt, C)mposed of calcareous shales and limestones, belonging to the Chickamauga series. These rocks, in part, form the valley, and in part, constitute the base of the western side of Taylor's ridge. Owing to a synclinal basin, the same formation occurs on both sides .af Dirt Seller mountain, and extends northeastward, to near the county line. Another belt overlies the Knox dolomite, entering the State near Menlo, and forms a valley at the foot of Shinbone ridge. All these valleys are comparatively narrow, but contain fertile lands.
RED MOUNTAIN SERIES.
Taylor's ridge crosses the county, interrupted, however, by a .dislocation to the eastward of Holland. High Point reaches an altitude of 1,606 feet above the sea, but the range is serrated with depressions recurring at 200 feet, or more, below this higher elevation. However, the mountain forms a characteristic feature, rising 600 to 800 feet above the valleys to the west. It is generally a portion of a synclinal elevation. This synclinal structure may be seen at High Point, where the rods dip at 60 N. 30 W. At this point, the lower portion of the mountain i~:> composed of shales and thick layers of gray sandstone, above which there are other sandstones which are of red or brown color. Farther north, the strata dip to the southeast, but come up again after forming an anticlinal basin at the southeastern end of the West Armuchee

GEOLOGY OF OHATTOOGA COUNTY.

125

valley. Again, these strata dip at low angles to the southeast, and then rising reappear in Dick's ridge. Thus Dirt Town valley, and its continuation, 'Vest Armuchee valley, forms a synclinal basin, but with the central portion of it broken by the anticlinal ridge west of Subligna.
East of Summerville, a good section of the rocks is seen along 10 S. 60 E. Near the top of the pass, the dip increases to 20. the newly excavated road. Upon the eastern side the dip is Upon the western side of the mountain there is an abnormal dip of 20 S. 60 W.; but farther west, the rocks dip normally towards the southeast. The thickness is 1,100 feet. In this locality, the higher rocks are composed of shales, underlaid by earthy sandstone, rarely thicker than one foot, separated by shaly partings. Some of the ledges are composed of :1 fine brown sandstone; others are mottled; but nowhere are the strata more than two feet thick. The lower beds of the series are mostly shales. The fossil ore bed lies above the heavier sandstone layers, and is seen at several localities, with a thickneEs of about twenty inches, forming a bed, dipping rather more steeply than the eastern face to the mountain, along which it is occasionally expol'ed in ravines.
John's mountain is a bold ridge about twenty miles long, and is, geologically, part of a chain of dislocated ridges of the Heel Mountain series, connecting Rocky Face, Horn's, and Taylor's ridges, and has an elevation of 800 or 900 feet above the valley. It is capped with heavy ledges of sandstone, having a thickness of about 200 feet, interbedded with some shales. The lower part of the formation is shaly. In the central part of the mountain the rocks dip from 20 to 25 S. 60 E., and pass under the Sub-Carboniferous basin t0 the east.
Dirt Seller mountain forms a synclinal basin of the Red Mountain series, embracing the beds of the series as high up as the fossil ore, which occupies the trough a few feet below the snrfaee shales. The ore has a thickness of between one and two feet ..

126

GEOLOGY OF THE PALEOZOIC GROUP.

This mountain is the only plateau-like elevation composed of the Red Mountain series.
Upon. the,eastera side of.Pi~on m(lpntain, Shinbone ridge consists of a serrated chain of hills, rising from 200 to 250 feet above the valley. This ridge is the outcrop of the Red Mountain series, which passes under Pigeon mountain in a synclinal trough. The higher points of this chain of hills have been preserved by the capping of cherty gravel or fragments of rock derived from the Fort Payne series. The strata dip at 20 N. 50 W., which may be taken as an average dip, but in placE's the beds are much disturbed, and even dip at75. Whilst the rocks are mostly shales, with occasional flags of limestone, yet the shales form compact, thick lamination.,, and pass into sandy flagstones of red color. This red col<ar a,rises,from the surface weather.ing, as the rocks exposed at depths in the mines are of the more bluish cast; so also below the drainage level the sandy shales become more calcareous, and pass into impure limestones.
Throughout Shinbone ridge the 'fossil ore' beds are more or less constantly represented, and have a thickness of from two to three and a half feet. They are sometimes broken up into two or ffilre layers.

CHATTANOOGA BLACK SHALES.
Upon the western side of Taylor's ridge, and upon the western side of Shinbone r-idge, from ten to fifteen feet of black &hales occur. \Vhere not weathered, these shales are hard and compact, and are often mistaken for coal; however, they are usually covered with overlying deposits, and are only exposed along occasional r-treams.
SUBCARBONIFEROlTS SERIES.
This formation occupies the greq.,ter portion of Dirt Town and West Armuchee valleys. The rocks adjacent to the black shales at

GEOI"OGY OF CHATTOOGA COUNTY.

127

the foot of Taylor's ridge are cherty limestones of the Fort Payne seri.es, which give rise to gray, gravelly ridges. The gravels also occur upon the eastern, side, of.the; valJey, as they rise over the Red Mountain series. Yellow and black shales, with some low ridgemaking sandstones, and occasional limestones of the Floyd series, give rise to the rolling valley lands, with indifferent soils in the less calcl\reous portions of the formation; still, there is much good land throughout these valleys.
Along the foot of Lookout mountain, there is a valley composed of Sub-Carboniferous limestone. On the eastern side, the rocks belong to the Fort Payne chert series, consisting of cherty limestones, which, upon decay, leave flinty fragments, such as are scattered over the western side of Shinbone ridge. The n1lley, however, is free from this gravel, as it is excava~ed O!.lt of the Motmtain
Limestone, which forms the base of the table-l~nd. This limestone
i:s a compact, more or less pure, blue rock. It is best developed in Walker county.

GOAL MEASURES.
East of Dirt Town valley, occupying a synclinal basin, a remnant of the Coal Measures occurs ou Little Sand mountain, which rises from 300 to 500 feet above the valley. The lower part of the mountain consists of shale succeeded by sandstones, which are massive, but in layers of moderate thickness. The surface of the southern end of the mouutain forms a basin, drained hy Mill creek, which cascades over a ledge of sandstone 15 or 20 feet thick. Descending the little chasm of the horse shoe falls, there is a layer of rock, more or less shaly, having a thickness of 15 inches, through which a dozen seams of coal are scattered, each with a thickness of a quarter or a half an inch. From this plateau a ridge extends some miles northward, composed of the same rock. No other coal i11 known upon it than that just described. The surface of the mountain is covered with light, sandy soil. This outlying basin of the

128

GEOLOGY OF THE PALEOZOIC GROUP.

Coal Measures is of interest oti account of indicating the eastward extension of the series. Little Sand mountain is cut off from the same formation of the Lookout plateau by a distance of about fifteen miles, with high Taylor's ridge intervening. Yet there is no doubt that the two plateaus were connected before the mountain movements, :whid1 have faulted and folded the intervening region, fl'Om which all of the lower formations have been more or less removed by erosion, with the preservation of their remnants, due to

FIGURE 20.-'fbis shows a section of fiftee n miles, from which the Coal Measures and other fc>rmations hav e been removed by denuilation, with the formation of valleys. The denuded beds from Coal Measures (C) to Middle Cambrian (Mo) are represented by clotteJ lines. F, great faults.
their hardy materials, resisting the diminishing power of degradation as the streams reached the base level of erosion. As the Coal Measures then capped Taylor's ridge, and all of the country thence to Pigeon mountain, the amount of material removed from the surface may be roughly estimated at not less than from 2,000 to 6,000 feet, as is represented in figure 20. The mountain movements have taken place since the commencement of this great erosion. A similar outlier occurs in Floyd county.
Lookout mountain forms a plateau cros~:>ing the extreme northwestern corner of the county, and rises up to 1,700 or 1,800 feet above the sea. The lower strata of the Coal Measures consist of shales which are mostly concealed, whilst the upper part of the mountain is bounded by a wall of sandstone or conglomerate (see plate VI., page 53) often in thick or heavy beds. Back from the brow of the mountain, higher beds of the formation occur. The

GEOLOGY OF CHATTOOGA COUNTY.

129

dip of the rocks, as seen in Neal's gap, averages from 5 to 10 N. 60 W.
Beneath the conglomerate at least one bed of coal occurs, having a thickness:of from 1 to 1} feet at the locality where seen-a mile north of Neal's gap. This is a portion of the wide-spread coal seam. At Gilreath's mill, the south fork of Little river cascades over the sandstones, belowlwhich the coal is again seen.
The top of the mountain consists of sandy soil derived from the di sintegration of the sandstones and sandy shales.
(9)

130

GEOLOGY O.F THE PALEOZOIC GROUP.

CHAPTER XVIII.
LOCAL GEOLOGY OF WALKER COUNTY.
GONTENTS.
OosTANAULA SERIES. KNOX SERIES. CHICKA.MAUGA SERIES. RED MoUN'l'AIN SERJES. CHATTANOOGA BLACK SHALES. S un-OARll ONIFERous SERIEs. COAL MEASURES.
OOSTANAULA SERIES.
East of Taylor's ridge a belt of Cambrian shales enters the county from Catoosa, and terminates southwest of Villa now. It is brought into position owing to a fault upon its western side, and the subsequent removal of the Knox formation from the valley at the head of E ast ArmucbPe creek. In part, these are low ridges produced by the sandy members ,vhich are present in the series; otherwise, tile belt forms a valley. Through the central part of the valley, the most western basin of the shales connects the siMilar basihs in Catoosa and Chattooga counties. This is an anticlinal valley, occupied by the usual fertile soils. The rocks are shales or sandy shales, the remnants of decayed calcareous rocks. Included amongst these shales, beds of limestones occur, which are exposed along the streams as is the case everywhere over this formation.
KNOX DOLOMITE SERIES.
East of Dick's ridge, as also east of John's mottntain, ridges with
of rolling valleys, carved out 'this 'fcirniation, form prominent feat-

GEOLOGY OF WALKER COUNTY.

131

ures. These ridges are repeated, owing to an anticlinal and fault structure. The soil on the ridge is usually covered with chert, and on the rolling lowlands, it is gray, with only occasional basins of red material. Between Villanow and Furnace at end of John's. mountain, the beds of dolomite rock are well shown and dip gently southeastward.
Between Taylor's ridge and Lafayette, there is a broad belt of the Knox series, which forms undulating valley land with occasional ridges. Here the soils are gray or cherty upon the ridges. This belt constitutes the eastern slope of the Lafayette anticlinal valley. The western side of the anticlinal forms a narrow chain o ridges of the same formation. These ridges are much interruptedi by valley depressions.
Missionary ridge, with the rolling lands in front, is also composed of Knox dolomite, and occupies the position of an anticlinal from which the rocks have not been sufficiently eroded to exposethe underlying Oostanaula series, as in the Lafayette (town) anticlinal valley. The ridges are often deeply covered with chert,.and the rolling valley lands are composed of cherty or gray soil, with occasional developments of red land. At several points, the streams. have exposed the rocks to a limited extent.

CHICKAMAUGA SERIES.
A narrow belt of these deposits skirts the western side of Horn's mountain, and unites with the synclinal basin surrounding the northern end of John's mountain. Two small exposures are seen passing under Dick's ridge. These limestones and shales are valley-making. Occasionally the limestone is exposed at the surface, as also sandy flags which are probably the remains of impure limestones. These rocks give rise to rough roads where highways. cross them.
West of Taylor's ridge another belt of the same formation under-

GEOLOGY OJ<' THE PALEOZOIC GROUP.
lies a valley along the foot of the mountain, from which the rocks extend upward into the base of the ridge.
East of Missionary ridge, and occupying the valley of the 'Vest "Chickamauga creek, there is a synclinal valley occupied by the lime:stones and shales of this formation; indeed, it is from this region .that the local geological name has heen adopted by Mr. Hayes. 1V hilst there are usually fertile red soils in this valley, yet the lime.,tones, dipping at low angles, form outcrops of considerable extent, which give rise to thin soils and rough roads. Besides the more or less impure limestones there are beds of calcareous shales, some of which produce rough sandy flags upon weathering. The sbaly members cannot be separated fmm the limestones in the series. The same rocks ri::;e up on the western side of the Missionary ridge anticlinal. Another small basin surrounded with the Red Mountain ridges rises up through the northern end of the Missionary ridge anticlinal, forming the typical basin of the reel or brown lands.
RED :010UN'l'AIN SERIES.
In the eastern part of the county, the northern end of ,John':-~ mountain rises to form a bold feature. This, as well as Mill creek ridge (forming a part of the connection between Horn'.-; mountain and Rocky Face), is composed uf the rocks of the Red Mountain series. On these mountains the sandstone members predominate to :-;uch an extent as to give rise to the bold features.
Taylor's mountain and Dick's ridge togethet f<mn a synclinal elevation. South of Gteenbush they enclose the \Vest Armuchee valley of Sub-Carboniferous ro ks. Extending n rthw:uJ iu t the edge of Whitfield county, the : amc ridges nclo e two I a i.n,. of
Sub-Carboniferous rocks, in 11nt:~ 'I mposed of the F ort I nync serie" <Lnd in pnrt of lll.oyd shn leii. Very g od .~~ tiou ao be ol taiucd by cr s iug tL'o m 11 ntuiu n 'o tdou j)l'inrrR or Gte Llbu. l. Tlt lower part f th formnti ou 1H1 il'lts 1 f thin betlded .lull ~~ but the
{q p 1' 150 feet of the mouutai 11 cunhtiu an e,ces.~ of . anti. to ne,

GEOLOGY OF WALKER COUNTY.
often in beds even to eight feet in thickness. Some of these hard sandstones have brown or red colors. On the eastern side of the mountain, west of Greenbush, the shaly beds are concealed between the dark ferruginous soil. Overlying the sandstone horizon, the fossil ore bed is developed, and has a thickness of one foot or more, exposed in ravines. The rocks dip 20 S. 60 E. on the ridge west of Greenbush ; but upon the eastern edge of the synclinal at Wood's gap, where the strata rise to form Dick's ridge, the red sandstones of the series dip 80 N. 60 W. The iron ore is also exposed
here, as also at Mr. J. Hamilton's to the north, where the rocks dip,
upon the western side ofthe synclinal, at 25 S. 60 E., and on the east side of the synclinal at 25 N. 60 W. The iron ore occurs above the sandstones, and in the synclinal basin of the formation.
Shinbone ridge skirts Pigeon mountain and passes round the head of McLamore's cove, and thence skirts the foot of Lookout mountain. It forms a chain of narrow serrated ridges, rising 100 to 200 feet above the adjacent valleys. The higher points are frequently protected by a cappiug of cherty gravel belonging to the Fort Payne series. In these ridges the rocks are not generally well exposed at the surface, owing to the easy disintegration of the Red Mountain series,-being mostly composed of shale, often in thick layers with only occasional flaggy beds of sandstone or impure limestone. Some of these flaggy beds are the remnants of impure limestones from which the calcareous matter has been leached out; for in the mines at Bronco the calcareous beds are preserved below the drainage level; whilst at the surface only the red r,;hale and flags appear. This extends and occupies a synclinal basin under Pigeon mountain, as also another basin beneath Lookout mountain, and a small basin surrounding Chickamauga limestones at the northern end of the Chickamauga anticlinal valley. Whilst these rocks are often in beds dipping from 15 to 20, yet they are occasionally folded, an1. even overturned as may be seen at Bronco mines.

134

GEOLOGY OF THE PALEOZOIC GROUP.

Another example of disturbance of the beds is seen at the W essboro mines north of High Point. There the strata undulate very much; still the normal dip is 20 N. 70 W.; but the strata may be seen dipping even to 70, and at the same time faulted. This disturbance involves the ore beds, which superficially appear to be duplicated. The structure is best seen in figure 21.

FIGURE 21.-At Wessboro mines. Folding and faulting (F) of beds. Ore bed (0).
The best exposed section of the Red Mountain series is along the railroad at the tunnel under the end of Pigeon mountain, where the shales are exposed for a distance of about 7,000 feet, across the formation, between the Chickamauga limestones and the black Devonian shales at the western end of the tunnel. The rocks dip
s: moderately regularly at 8 60 E. The whole formation may
be said to be composed of shales, sometimes in thin layers, and sometimes more sandy in the form of flag-stones, with occasional beds of sandstone, which seldom reach a thickness of more than 14 inches. As all of these shales are above the drainage level, they are mostly weathered to a red or brown color, although occasionally blue. The whole thickness of the formation is 1,100 feet. The fossil ore bed, with a thickness of two feet, or more, is here divided, and in position, it is situated about 700 feet above the base of the series. At Blue Bird gap, near by, the formation is aho well exposed.
Along the Chickamauga and Lookout Railway, approaching Eagle cliff, a section of the Red Mountain rocks is exposed. The average dip of the strata is 20 N. 70 W., although there are some undulations in the successions. The total thickness is about

GEOLOGY OF WALKER COUNTY.

135

800 feet. The rocks are mostly shales, sometimes thin bet-lded, but at other times in massive layers, which are more or less sandy. Some thin sandstones occur in the upper part of the series, near which is the ore bed. The ore bed is moderately constant throughout the Shinbone ridge. The characters of these rocks, in the anticlinal basin, at the northern end of the Missionary ridge are similar to those of Shinbone ridge. For the characters of the ore see Economic Report.
CHATTANOOGA BLACK SHALE.
Overlying the Red Mountain formation of Shinbone ridge, as well as Taylor's ridge and 'Horn's mountain, from 10 to 20 feet of black shales of the Devonian system occur. These probably belong to the upper part of that system, and whilst unconformity to the lower series was not detected, yet there is. an apparentygap in the succession. This failure of detecting unconformity arises in part, from the small development of shales, which are rarely exposed at the surface by the infrequent streams. The best exposure of these shales, is at the western end of the Pigeon mountain tunnel; occasionally they are dug into, by mistake, for coal. As a surface feature these shales are unimportant.
SUBCARBONIFEROUS SERIES.
In the extreme southeastern corner of the county, there is a small exposure of cherty surface deposits, upon Horn's mo~mtain, belonging to this series. Along its margins, Armuchee valley consists of soils derived from the Fort Payne chert, and in the interior, from Floyd shales. Some of these shales are interbedded with 1imestones.
Round the end of Pigeon mountain, there is a great development of Sub-Carboniferous limestones. These are seen on the ridges bordering the Red Mountain formations. At the north end of Pigeon mountain, as shown at. the tunnel, the lower member, or the Fort Payne chert, is composed of about 250 feet of limestones,

136

GEOLOGY OF THE PALEOZOIC GROUP.

charged with nodules or bands of chert. Adjacent hills are thickly covered with the disintegrated cherty gravel. The Fort Payne cherts are traceable upon the serrated hills of the Red Mountain series, round the head of McLamore's cove, and along the eastern foot of Lookout mountain.
The Mountain Limestone consists of compact, bluish limestone, mostly pure and in thick beds: It also contains some unimportant seams of shale, and one of sandstone. It is best developed at the northern eud of Pigeon mountain, where it has a thickness of about 900 feet. This limestonE\ is also traceable round McLamore's coye and Lookout mountain, and constitutes the lower slopes of the plateau. The narrow valleys, between the cherty ridges and the mountain are composed of soils, the result of weathering of this limestone. At the northern end of Lookout mountain, there is an excellent exposnre, where the limestones appear to have a thickness of 700 feet, but those to the south are not so thick. The upper portion of the limestone becomes impure and somewhat flaggy, passing by transition into the shales of the overlying formation.

COAL MEASURES.
Pigeon mountain is a spur of Lookout, and is a synclinal plateau, surmounted by Coal Measures. At the head of McLamore's cove, these consist of laminated sandstones, with an average dip from 5 to 10 S. 20 E., but locally dipping to the southwest. Of these sandstones 125 feet are seen. Beneath the sandstones 65 feet of sandy shales occur, underlaid by 10 feet of heavy bedded sandy shales. The lower 250 feet of shales are laminated without hard layers. The undulations of the surface of the mountain, in this locality depend upon the dip of the strata, whereby the sandstones arc carried to higher altitudes; but over these sandstones just named, at some higher points, shales occur. About a mile and a half to the northeast of the head of the cove, or Dougherty's gap, in a valley opening northward, about 150 feet of sandstones are

GEOLOGY OF WALKER COU:XTY.

137

seen, beneath which there is a bed of coal about a foot thick. In

this gorge, the rocks, upon the right bank, dip southwestward, and

on the opposite side to the northeast, making a steep synclinal,

with the strata dipping from 15 to 20. The highest point of

Pigeon mountain rises to 2,321 feet, with the sandstones just de-

scribed, forming the floor of the sloping plateau, with precipitous

cliffs on the western side.

Pigeon mountain above Bronco shows the following section in

descending order :

Feet

Sandstones of variable character. __

_ 10

Sandy and ordinary shales

90

Yellow sandsto11e__ __

-- ~ 10

Sandy shales mostly concealed __ .. . _ ___ . . ... . _

10

Sandstones in thick, but with false, bedding _ . _.

___155

Shales and sandy shales_ __ --- - _ ____ _ _____ 260

Sandstones with some conglomerate in thick beds, dipping

5 to 10 westward _____ .

.. - - -

. 40

The rocks above the thick sandstone, are located in the interior

of the mountain, and belong to the Upper Coal Measures. The

thick sandstone forms au escarpment around the mountain. (See

plate V., page 53.) At the northern end of the mountain, High

Point is composed of the sam<;J ledge of heavy sandstones, as have

just been described; 'l'he formation is not more than from 300 to

350 feet thick, at the point where the Mountain Limestone rises to

nearly 1,100 feet above the valley.

The Coal Measures, consisting mostly of shales below, with heavy

beds of sandstone above, characterize Lookout mountain, which

taken as a whole, is a synclinal, plateau, the same as Pigeon moun-

t.ain. These synclinals, are, however, parallel.

At the north end of Lookout mountain, the Coal Measures are

exposed in the following section, which does not, however, include

the highest members of the series shown in the basin to the south:

138

GEOLOGY OF THE PALEOZOIC GROUP.

1Jpper conglomerate or sandstone, consisting of variable

Feet

layers of sandstone in false bedding, with the lower 50

feet, mostly as a massive conglomerate, in which there

is a coal film ________ __________ --- -- -- --- - --- --- - 225

:Shales and sandy shalf's of variable thickness ____ ___________ 35

Lower sandstone and conglomerate containing some shale _____ 40

.Shale and sandy shale containing coal film _______ .. ________ 50

.Sandstone _______ ______ -- - --- -- ---- ----- - - ____ ...15 to 20

Shale and sandy shale, with thin sandstone near the top. ___ 280

.Sandstone (with shales below, passing into limestone) _______ 10

660 The rocks at the end of the mountain forma syndical basin with the rocks dipping at low angles; but on the eastern side of the mountain the dip incrpases to 70 N. 60 W.; this, however, is reduced in the exposures of the Fort Payne chert, near the foot of the mountain. Whilst the above section represents the series beneath the other beds, the section shown along the Chickamauga railroad, from Eagle cliff to Round mountain, gives the best section from the lower sandstones upward. At Eagle cliff the rocks dip :20 N . 70 to 80 W., flattening out into undulations to the southward; to the northward, the strata locally dip at about 45 to the n r t:lnv s . Tb ~ agl cliff i CUJ )_ ed v tlt upp 1' co.nglomerute
.of' L 11 ou,t p in t hi. ame co u lomcmte reaolt inr High Pint to th e sou~ r i&ing to n.n t~ l vati n f 2 4 feet' above h ea., l>u t Joe.: not incl n] he bigh !:it. 1ed _f h 1oal Measures, whiol1
occnr in the interior of the mountain, and on Round mountain. The following section is obtained from the careful reduction of the measurements along the Chickamauga railroad. It extends from the top of Round mountain to the base of Eagle cliff.
FRet Laminated shales with a few layers of sandstone on
Round mountain (partly concealed) . . ____ _ . __ 200

GEOLOGY OF WALKER COUNTY.

139

Feet

Shales ? (concealed)---- ..... ~ _ _ _____ ----- - _ 65 Shale _____ __________________________ .. __ .. ____ .. _ 9

Coal and shale intimately interlaminated .. . __ _

14

.Shale aml ~;audy shale, partly concealed __ _ _____ ___ 25

Coal_ ___ ____ __ __ __ ___ ___ _ ___ __________ _

0.7

.Shale ________ __ ----------------- ../ ___ -------- 18

Sandstone, gray laminated ______________________ .. _ 35

Coal (3.5 to 4.5 feet) dips 1 E. S. E. ; altitude at mouth of Durham seam mine, 1,849 feet above tide. There is a

slaty parting in the middle of the seam. This bed is probably represented on the southwest side of the mountain at an altitude 30 feet lower___________ ___ 4

:Sandstone, irregularly and often thinly bedded and un-

dubting_ ------- ----- - ---------- ____

_ 80

Red shale _______ .. _ __ . ____ . _ _ __ _. _ __ _ 11

Black shale,_______ _

4

Shale and sandy shale with a seam of limestone ____ . __ 10

Blue shale above and variegated shale below _ _ _

7

Coal (alt.itude 1,668 feet)---- - - __ _ ______ _ _

1.8

Thin laminated blue shales

__ ____ __

70

Red shales _____ .

_ __ .

35

Coal _ . __ __ __ __ ____ . _ .. _

.2

Light blue clay ____________________ _____ .-~ -- -- - 2

.Shales and sandy shales, passing into sandstones and un-

dulating so as to frequently appear and disappear for

a distance of 3 miles, but characterized by some recog-

nizable layers, estimated at__ _ _______ _________ ___ 150

CoaL ___ _.,

1.7

Sandy shales in steep undulation .. __ _ _ __

1 to 3

Heavy bedded sandstones _____ . _ _ __ ___ . ____ . - -- 25

Coal ____ .. ______ __ __ ________________ _ __ _ ___ _

0.2-0.8

Upper conglomerate and sandstone (at Eagle cliff) __ __.150

140

GEOLOGY OF THE PALEOZOIC GROUP.

:Feet

Shales laminated and also thick bedded ___ ___ __. _- _120

Lower conglomerate and sandstone __ __ . - ________ 40

Shales, more or less concealed __ __ _ _ ______ .. _(~) 250

On the southwestern side of Round mountain, there are proba-

bly two coal seams, different from and situated above the coal seams

given in the above table. Beneath the upper conglomerate a bed

of coal occurs with a thickness of from one to three feet, and said

to be still thicker at some points. These coal seams are, probably,

identical with thm;e at the bead of McLamore's cove and in Pigeon

mountain.

The coal seamsbeneath the upper conglomerate are in the same

position with others seen at various points near Rising Fawn. One

of these coal bedR occurs at Stephens' gap on the east side of John-

son's creek, beneath the sandstone, which dips 18 S. 60 E., rest-

ing upon fire clay. Above the furnace, on the northern side of

the creek, there is a vein of coal formel'ly opened. This Yein oc-

curs in shales at a considerable depth below the conglomerate. The

vein is said to vary from nothing to eight feet in thickness. Near

the point of the mountain, to the west, another vein of coal occurs

immediately below the conglomerate.

As the mountain has been unequally eroded, especially "here the

conglomerate is brought into high angles on the eastern side, the

upper sandstones have been removed in places, as also some of the

underlying shales and coals. The erosion must have been great,

as the Coal Measures above the conglomerate have been generally

denuded, except where protected by the form of the basin of Look-

out plateau.



GEOI,OGY OF DADE COUNTY.

141

CHAPTER XIX.
LOCAL GEOLOGY OF DADE COUNTY.
CONTENT.;.
KNOX SERIES. CHICKAMAUGA SERIES. RED MouN1'AIN SERIES. CHATTANOOGA BLACK SHALE. Sun-CARIIONIFF:Rous SERIH:8.
UoAL M E11SURES.
KNOX SE-&~5.
Cherty ridges of the Knox dolomite formation enter t.he county from Alabama and extend only a few miles into Georgia, south of Rising Fawn. These are the lowest rock series of the anticlinal valley of Lookout creek.
CHICKAMAUGA SlRIES.
On both sides of the anticlinal exposure of the Knox series there are developments of the Chickamauga formation. The limestones are conspicuous, 'and form strata dipping from the valleys often at low angles in both directions. Whilst they are in part valley making, yet some of the rocks rise ~1p 'in ridges or make a stony floor to the valley. Some of the' beds include light colored, fine grained limestones, breaking with a conchoidal fracture.
From a point north of Rising Fawn, down the Lookout valley, the Chickamauga series forms a fertile valley, whete the soils are of red or brown color derived from impure limestones. In places these rocks are more or less massive beds of impure, often flaggy limestone, coming to the surface and forming low ridges. Else-

142

GEOLOGY OF 'l'HE PALEOZOIC GROUP.

where the ' decayed soil deeply covers the undecayed rocks. Whilst. the beds mostly dip at angles from 10 to 20, yet portions of the folJs dip as much as 60. The formation is about 1,200 feet thick.
RED MO"UNTAIN SERIES.
Both basins of the Chickamanga limestones are surrounded by chains of undulating ridges rising from 100 to 300 feet above the valleys. The higher points are, however, commonly protected by cherty covering of the Fort Payne chert, or sometimes by remnants of the cherty limestone itself. The character of the ridges may be seen in plate V., page 5:3. The rocks are mostly laminated shales with some flaggy layers, and of a red color above the drainage level. There a1e occasional thin layers of limestones. Below the drainage level the rocks are more calcareous. The fossil ore is usually present in from one- to three beds, and has a thickness varying from two to even seven feet, but usually it is not over two and a half feet thick, especially above the drainage level. Below that horizon the ore is always highly calcareous. On the eastern side of the valley the formation passes under Lookout mountain, and on the western side, it passes under Sand mountain.
CHATTANOOGA BLACK SHALE.
Overlying the Red Mountain series, the Devonian black shale everywhere succeeds it. As this shale is very easily disintegrated and removed, it is only preserved beneath cappings of the next formation. As a consequence, it is seldom seen except in occasional washouts or along streams, or along roadsides where <mts have been made. Its thickness does not exceed ten or twenty feel..
SUB-CARBONfFEROUS SERII<:S.
The Fort Payne chert is best known'from the rough cherty fragments which commonly form a thick mantle succeeding the ridges of the RedMountain formation, on the lower portion of the mountain sides, where, however, streams often expose the natural rock.

GEOLOGY OF DADE COUNTY.
Near the Rising Fawn furnace, the Fort Payne chert has a thickness of about 200 feet. It. is also well shown east of New England City, owing to some extensive quarrying. Occasionally upon the serrated hills of the Red Mountain series, the cherty limestone ispr!)served, and weathers into castellated towers, as near the southern end of ihe hills where the two sheets of the ore beds come together. The flinty material is sometimes uniformly distributed through the somewhat thin beds of limestones, again it forms seams, or else it makes up most of the beds. In weathering, pockets of clay are often left and these may be of the nature of kaolin or other valuable clayey deposits.
Between the cherty ridges and the mountains there are narrow: valleys formed out of the overlying rocks of' the Mountain Lime-stone series. Whilst these rocks are not mountain making of themselves, yet along the foot of Lookout and Sand mountains they are protected by the overlying sandstones, and form more or less of the base and sides of the plateaus. They are usually compact blue limestones in thick beds. The upper beds have thinner laminations and are less pure, and somewhat sandy. The thickness of the formation is about .500 feet. Owing to coverings by superficial clays,. derived from the weathering of the superior rocks, the limestone~;. are more or less cemented. Below Cole City the limestones .are exposed along Nickajack creek.
COAL MEASURES.
Lookout mountain Coal Measures have already been described iw Walker county, as most of the plateau lies in that county. In, Lookout valley there are two remnants of the Coal Measures left-on. Fox mountain and on the plateau above Whiteside.
Sand mountain is capped with the Coal Measures. On its eastern. side, however, the sandstone, which corresponds to the conglomerate of Lookout mountain, has been removed in many placesowing to denudation.

144

GEOLOGY OF '.rHE PALEOZOIC GROUP.

The highest beds of the series lie about three miles north of Cole

City, near Mr. Liedermann's. On the top of the ridge twenty feet

of heavy sandstones remain. Amongst shales, 75 feet beneath the

top of the sand&otone, a bed of coal occurs. The lower beds are

concealed, but they are probably mostly composed of shales. They

represent a vertical elevation of 250 feet above Cole City. As the

direction is along the strike of the formation, this measurement may

be taken for the thickness of the upper beds on Sand mountain, in

Georgia. From Cole City downward a good section can be ob-

tained. Yet the strata are liable to local \ ariation, and thicken or

thin out so as to give 0onsiderable variation in different sections.

The rocks generally dip at low angles, to almost horizontal, al-

though locally thete are steeper inclinations.

Along the railroad from the coal mine3 to the coke ovens a good

section of the series, except the upper portion, can be obtained.

The beds lie nearly level or undulate very slightly.

Feet

Irregularly bedded sandstone or conglomerate ____ .

70

Castle rock coal __ _ __ _ Shale ___ _ __ _

_wanting 40

Dade coal seam _____ ___ ___ _ ___ ____ _

average 3

Sandstone and sandy shale, Yariable ___ ___ __ -- - ---- _12

Coal (Reese's red ash seam) __ _

-3

Shale_ _ _ _ . ____ ___ _

6

Sandstones, or conglomerate-upper half thin bedded, lower

half thicker, with shaly seams ___ _ -

__ . - -- _- 20

Coal variable ______

. _ ___ ____ __ .. ___ 0.5-3

Sundstonesandsbales ..

_ -- __ _ _ _ __ __ __ _, 10

Blue shales . __ _

___- - ____ _____

_10

Sandstones, thin bedded, and shales or sandy shales____ _ .15

Coal 3 to 15 inches _ __ _ _ . __ _ _

1 . 25

Shales, middle layers heavy bedded_ Coal smut.. _______ _

_ _f.,<j

GEOLOGY OJ<' DADE COUNTY.

145-

Shale ___ _ ---- -- ----- -_

Feet _ _15

Coal smut_ ___ __ __ _ _____ ~ ___ .. ____ _ _______ . _________

Shale __ . _ ___ ____ _ ___ ----- _ ______ _ __ _ ___ 4

Concr:>tionary beds ____ - ___________________ - _ . _______ 6.

Shale __ ___ _ _________ - ----

_ ----- _ 15

.. Sandstones, thick bedded _______________ . ___ __________ 15.

Shale ______ _____ ___________ __

----- - .. 10

Shale with some thin layers of sandstones __

__ 95 .

Shales(?) concealed .. --- _ ___ -- -- -

______ 90

Limestones ____________ ------------- ____________ . __ -

Other lE)ss perfect sections and borings have been obtained~

some of 'Yhich are given in the Economic report.

The Coal Measures give rise to light sandy lands. The shales ex

posed at the surface are usually weathered red, but those seen m.

the mines, below atmospheric actiob, are generally dark blue.

(10)

146

GEOLOGY OF THE PALEOZOIC GROUP.

CHAPTER XX.
RECEN'r FORMATIONS WEST OF TAYLOR'S RIDGE.
West of Rocky Face and Taylor's ridge, none of the gravels
which have been referred to the Lafayette formation were seen, nor
were the red loams; but these last might have escaped observation where there was no gravel, as they are superficially difficult of distinction from red residual clays. The valleys are very little higher than the lands of the Coosa basin. The explanation may lie in the fact that the district referred to stood a little higher than the Coosa basin during the submergence which allowed the yalleys of the Coosa basin to have been submerged. At any rate the quartz gravel eoming from the metamorphic highlands to the east would have been obstructed by Taylor's ridge. Still west of this regioQ, there were hard sandstones which could have supplied material for the production of gravel. At any rate, if loam were laid down, during the Lafayette epoch, it has been removed by subsequent denudation to such a degree as not to attract attention at the present time.
As the rivers have not made extensive flood plains the bottom lauds are not conspicuous, although the streams overflow irregular lowlands to a limited extent. But it is not a country of true bottom lands.
The soil is everywhere the result of the rock decay, and varies according to the source. These residual earths eommonly cover up the undecayed rock formations, where the natural strata ate exposed in only exeeptionally favorable places; but the residual earths aRsist in locating the underlying formations.
The rocks are often sufficiently fossiliferous for their identification; and in the coal mines some beautiful plant remains occur.

PART II.
ECONOMIC RESOURCES
OF THE
PALEOZOIC GROUP
OF
GEORGIA,
IN POLK, FLOYD, BARTOW, GORDON, :MURRAY, WHITFIELD,
CATOOSA., CHATTOOGA, WALKER AND DADE COUNTIES.
llY
J. W. SPENCER.


ECOKOMJC RESOURCES.

149

ECONOMIC FEATURES
REPRESENTED ON THE GEOLOGICAL MAP.

COAL MEASURES .. . . .... . Coal, gray sandstone. MOUNTAIN LIMESTONE . Limestone and building material.

FLOYD SHALE . .... ..... .. Limestone and building material.

FORT PAY~E CHERT . . . Road metal, brown ore.

CHAT. BLACK SHALES ...

RED MOUNTAIN . .... . .. Fossil ore, brownstones and flagstones.

CHICKAMAUGA . . . .... Slate, limestone, iron ore, ochres.

KNOX DOLOMI'FE .. . . , ..

Brown iron ore, manganese, beauxite, limestone, kaolin, road metal.

OOSTANAULA SHALE ....

Cement, black metal.

marble, sandstone, road

THE

Iron and manganese ores, ochre, soapstone,

METAMORPHIC ROCKS

heavy spar, graphite.

N O'l'E.-The occurrence of the ores, building materials, soils, physical feature~, conditions of the roads, etc., are all dependent upon the geologieal stt..wture, and before any information, of scientific value, relating to their distribution and modes of occurrence could be given, it was necessary to prepare. a detailed nccount of the geological structure of the belt mrveyed. For information coucernmg the local geological conditions reference must be made to the first part of this report and to the geological map.

150

ECONOMIC RESOURCES.

CHAPTER XXI.
BROWN IRON ORE3 AND THEIR MODE'3 OF OCCURRENCE.
CONTENTS.
KINDS OF BROWN ORE. SouRcEs OF BROWN ORE. MoDES OF OccuRRENUE oF BROWN ORE: "Note, Iron Ore of the Knox Series; of
the Deaton Series ; of the Sub-Carboniferous Series.
KINDS OF ORE.
Except the "fossil ore," the most important iron deposits of the Paleozoic group belong to brown ores and limonite varieties.
Limonite, in its purer crystalline form, is more or less globular or botryoidal with the internal structure fibrous and more or1 less silky in luster, having a degree of hardness varying from 5 to 5.5. The color is dark, rich brown, and the luster is sometimes metallic. Other varieties have an earthy appearance, of dull yellow or yellowish brown color, and soft-varying from one to three or four degrees of hardness. According to the admixtures, the color of the powder varies from ochre to yellow brown.
In composition, limonite is a hydrous sesquioxide of iron, containing, when pure, iron, 59.92; oxygen, 15.68; water, 14.40 per cent. Commercially, the percentage of iron falls helow these figures on account of impurities. When limonite has lost its water, the mineral becomes hematite, and then the metal rises to 70 per cent. As a matter of fact, very little of the iron ores, passing under the name of brown ores in northwestern Georgia, are pure limonite, but are usually admixtures of this mineral with hematite derived from the former by the loss of the water. Thus the percentage of

BROWN IRON ORES.

151

iron is increased, as most of the available ores contain only two

to four per cent. of moisture. This mixture of iron bearing min-

erals is commercially known as "Brown Ore." This always con-

tains more or less admixture of clay and sand. Amongst the ele-

ments associated with the ores, in small quantities, which have a

bearing on the value of the iron, phosphorus only need be men-

tioned, as it renders the iron brittle when present in excess of mere

traces.

. .

The brown ores vary much in physical appearance, with the

modes of occnrrence and geological sources. It is frequently red,

earthy, in small concretionary particles and masses; occasionally

in large boulders; and again in irregular sheets. In all of the re -

sidual ores of the Paleozoic series, the appearance is much more

l"!arthy and of a darker color than the beds of brown ores, sue h

as are seen in the metamorphic rocks east of Cartersville, which

have often an ocherous appearance.

SOURCE OF THE BROWN ORE.
The brown ores of the older Paleozoic belt have been entirely derived from ferruginous limestones. Whether the iron was in the condition of carbonate or of sulphide is of little consequence, for where available it is now always associated with the remains of decayed limestones, some of which were highly calcareous with but little flinty matter; whilst again to a lesser extent, the iron deposits are derived from the siliceous beds, with a marked difference in character. Some of the iron bearing limestones may have been ferruginated after their formation, and that irregularly, by iron bearing streams, often flowing transversely, across the formations, from the older metamorphic rocks to the east; for frequently the trend of the ore bearing ridges is across the general direction of the formations, which normally extend from eastward of north to the opposite direction. Possibly, the directions of some of these former iron bearing stteams can be recognized; but probably

152

ECONOMIC RESOURCES.

a greater proportion of the ore has been deposited synchronous with the rock formations adjacent to mouths of streams, or in lagoons, or as pointed out, in connection with manganese and aluminum ores. As all the valuable deposits are of secondary origin, often derived from the concentration of the ore upon the decay of the limestone, commercially the questions are:
'' What fonnations contain o1'e, and what are the rnodes of occui'rence /"
The origin of the deposits is similar to that of manganese, a discussion of which appears under that head.

THE MODES OF OCCURRENCE OF BROWN ORE.
NO'l'E .
In the Geological Survey, the consideration of this subject is that of primary importance rather than a list of the known beds, a., the object of the survey is to aid in the development of the resources, and in making known the belts of the same. without the investigations recorded in the first part of this report, no key to the situation could have been obtained. Under such conditions the .survey would have been only a catalogue of discovered iron bearing properti es, without a scientific knowledge of the same. The applied deduction s are here given as if the reader were familiar with the first part of the report.
The principal brown ores occur in distinct Lower Paleozoie formations-the Knox dolomite and the Deaton ore series, but it -also occurs to a small extent in the Sub-Carboniferous series.

IRON ORE OF KNOX DOLOMITE SERIES.
From investigation, the first general deduction arrived at is the occurrence of the largest amount of workable ore upon subordinate -elevations in red land derived from the lower Knox strata. The () bservation that such ore deposits are abundantly situated near the margin of the Knox formation can now be extended and explained

PLATE Vll.
BROWN ORE RIDGE AND PITS, In residual Knox clays, at Grady, near Fish Creek, Pclk County.

BROWN IRON ORES.
from fuller surveys. This condition is dependent upon the accumulations of ore being largai\t in the lower and less siliceous numbers of the Knox series. These lower beds approach the surface, not merely along their northwestern margin, but where undulations of strata have brought the more calcareous beds to the surface. The presence of these beds has favored valley making, owing to their :solubility and the absence of a protective covering of chert. Thus, by the deformation of the stiata, the lower iron bearing beds are lifted up to view, adjacent to the underlying shale formations. But again, the ore deposits occur at no great geographical .distance from overlying Ordovician limestones and shales, and, near the junctions of the formations, as in the Cedartown and Fish creek districts. This, however, is due, pot to the presence of different formations, but to the undulations of strata and the elevation of lower beds, which have been reduced to valleys, owing to the removal of the C!\lcareous matter, in localities where the cherty beds have not been sufficiently protective. 'J'his same condition obtains where undulations of the Knox series is not overlaid by higher rocks, as northwestward of Fish creek, \vest of Seney and Dnward. Consequently, wherever there are broad valleys, carved out of low~r dolomite beds, with red lands, ore beds are more or less common, and accordingly, there are several parallel belts.
Naturally, the removal' of the calcareous matter, would produce valleys, wherever it comes to the surface, but the ore deposits re.'iist erosion and becomes more or less protective. Consequently, the brown ore is most commonly found on subordinate ridges in the valleys. (See plate VII. on oppoRite page.)
As already stated, the form of the ore is usually in small concretions, sometimes becoming large boulders, or occasionally beds of limited extent, very much disturbed. This refers to the ore in the red bilk The ore bank is an accumulation of ore deposit remaining from thte decay of a great thickness of rock, and in many places, it is known to be more than from 40 to 50 feet deep,

'

154

ECONOMIC RESOURCES.

above the natural drainage level; and often passing far below it in other localities. In these regions, but. little dependence, or indeed value need be placed upon the bedded portions. The accumulations pf the "wash" ore are of greatest value on account of their better quality and more ecDnomic working.
A characteristic of these ore beds is the rising up of ma~ses of clay-technically "horses" amongst the ore. .Often the clay is white or pink with but little iron, and standing up in strong contrast with the ore. These clays often show a commingling of much undecomposed feldspar, and appear to have been deposited as irregularly as they are now found. (See analyses under clays.)
The proportion of concretionary ore in the banks varies, but has been worked where it ;rields upon washing even less than onefifth of the mass; seldom is it more than one-half. The large oremasses, whilst being mostly made of limonite, are more expensive to work than the wash ore. The small ore has lost most of its water, and is usually of a brown or reddish color.
In portions of the cherty beds of Knox dolomite, brown ores occur similar to those just described, but their development is of less extent; perhaps due to the lower degree of concentration, owing to the protective mantles of siliceous matter. Again, vesicular beds of chert-the calcareous matter being removed and leaving the cavities-are often rich in iron, and occur in massive strata. The ore in such beds is usually too iililiceous for present use, and the wash ore is generally less extensively developed in these gray than in the red hills.
Between these two characters of beds-red hills rising in the Yalleys, and gray ridges-there are intermediate conditions; so that the sharp lines between the relations of the ores cannot always be defined.
Stratification is not usually seen in the residual accumulations, as is already noticed; and consequently, the tracing of the beds is rendered difficult. This absence arises, in part, from the disturbed

}'lO U R~: 22.""7White "clay horse" in brown .ore bunks ut Grady.

156

ECONOMIC RESOURCES.

condition of the strata, and, in part, from the irregular falling of the decayed beds into underground cavities, thus obliterating bed.ding. This is seen in some cases, as on the State line, in Etna pits, where some of the ferruginous rocks have been in heavy beds. (See plate VIII. beyond.)
The ferruginous beds can occasionally be. traced short distances and are then found to g1aduate into ocherous beds of clay, and .eventually become obliterated.
The ores of the Knox dolomite are often thickly strewn upon the surface of the low ridges, as pebbles, in size, from that of shot to large cobble stones, or boulders. In such cases, the ore may continue downward to the depth of nndecayed rock: The hills are of deep red color, not only from the presence of ore, but from the coloring in the clay. Othet portions of the hills are simply covered with deep red soil, and beneath them the ore is sometimes found. Such is especially the case when this covering is of the Lafayette series.
It may be stated here that when the Lafayette loam does not contain gravel, it is not aJ ways easily recognized from the residual !:iuperficial formations w.hich have the same general appearance.
The covering of the valuable ore beds is often shallow. It is seldom more than eight feet thick. In it, the quantity of the ore often reaches twelve or fifteen per cent., and justifies the washing of this coveritig sheet, but the amount is seldom enough to warrant its use when the ore is only screened.
Sometimes, the ore occurs b~neath day horses. In' these cases, it may soon become valueless, because of the masses of clay that must be first removed.

ORE OF '!'HE DEATO~ SERIES.
These ores differ in appearance from those of the Knox dolomite. They ne\er form_ concretionary or rounded gravel, but they make more or less angular shingle, scattered over the subordi-

BROWS IRON ORES.

157

nate ridges. When these deposits are worked tar enough, the ore is found more or les'l in beds of variable thickness. However, these beds often pass into ferruginous clays and soft ochres. (See plate I., frontispiece.)
The mineral is mor,;tly limonite and is often yellowish, but that exposed on surface is brown or red. It may be slightly magnetic, on account of being a8sociatecl with semi-metamorphic rocks. Thus, it appears, that the rocks were ferruginated before the metamorphism of the strata situated immediately to the south.
The ore is deri vecl from ferruginous limestone, which may be seen in Deaton mine, near Taylorville. Here is found a dark, undecomposed compact crystalline limestone, containing 25 per cent. of iron. But usually the rock is disintegrated, leaving beds of shingly ore. At this named locality, the underlying Maclurea limestone was rendered cavernous, and the roof being composed oi iron-limestones, has fallen in, making a confused mass of ore. This will be noted later and may also be seen in plate I. (Frontispiece.)
Ores of this horizon occur in low ridges in -Whitfield countyr lying in thick beds, associated with the limestone. The mineral, however, has a more specular appearance than seen at Deaton. These ores belong to a horizon which may be correlated with Safford's Iron-Limestone series.

ORE3 0&' THE SUB-CARBONIFEROUS SERIES.
The lower member of the Sub-Carboniferous series consists of the Fort Payne chert, a siliceous or cherty limestone, in which somelayers consist almost entirely of siliceous matter. In many localities some of these beds are highly ferruginous to such an extent as to give rise to beds of brown iron ore. Such may be seen on the ridges of southern Polk, where the ore is compact and approaches hematite in appearance.
In limited quantities the ore of the same horizon is sometimes

15 8

ECONOMIC RESOURCES.

seen in the extreme north western portion of the State. On Horn's mountain the .ferr!}ginous bed~ are near the base of the series immediately overlying the- hlaclf"shaJes' of the Devom1tn system, on the eastern flank of the mountain. The original rock is de_cayed, and the calcareous matter is almost entirely removed from the limestones, leaving a concentration of residual clays (sometimes in "horses") in which boulders and irregular laminations ofore occur iu workable quantities. If mining were carried below the drainage level, it is very doubtful if the ore would be sufficiently concentrated for an available supply of iron. This ore contains much more of the yellow limonite than the Knox ores.

BROWK IRON ORES.

159

CHAPTER XXII.
LOCAL DISTRIBUTION OF BROWN ORES.
CONTENTS.
K:wx ORES IN Por.K CouNTY: In the Basin We>i of Little Cedar Creek; Valley adjacent to E. T .. V. & G. Railwuy; Along East & West Railway of Alabama; Fish Creek District; Long District; Recapitulation.
KNox ORES lN FLOYD CouN'l'Y: Cave Spring District; Spring and Silver Creek Districts; Recapitulntion.
Kxox ORES IN BARTOW CouNTY: Flpring and Silver Creek Districts; Tom Creek and Connesenna Districts; Recnpitulation; Ores of the J'tieturnorphic Rocks.
Sun-CARBONIFERous OREs. DEATON ORES. BRowN ORES IN GoRDON, MuRRAY, WrnTFIELD, CATOOSA, CHAT'l'OOGA, W ALKEI\
AND DADE CouNTIE~: Knox Ores; Deaton Ores; Sub-Carboniferous Ores.
KNox OnEs IN PoLK CouN rY.
A portion of this county has already been reported on, but for the sake of fuller treatment of the subject, the general features gi veh before will be included in this present and more extensiye.report. Only a few properties in the:ore belt could be named, as every section bearing ore C)1Jld not be visited, but those mi.tn.ed will aid in the location of the richer belts in the ore bearing zone.
BROWN ORES IN. THE BASIN \\'EST OF THE LlT.rLE CEDA.II.. CREEK.
This is a basin about two miles wide and eight long, extending from Indian mountain, in Polk county, into Floyd. Owing to faults, this basin is isolated from the other portions of the Knox series. Here the country is made up of somewhat narrow valleys and rugged, gray, cherty ridges. In this basin, there are several

160

ECONOMIC RESOURCES.

deposits of brown ore of the usual type, but these often go below the drainage level. Thus, on the property of Mr. Linton Sparks, lots 139 and 140, 17th district, there are pockets of good and of indifferent ore, side by side, and these appear to have been derived from different beds. On the ridges near by there are several surface exposures of thick siliceous beds, some of which contain ore rich in iron. These sheets occur on. the Stott-Folger and other properties. Again, there are other ferruginous beds of ore of inferior value to the ore banks, which can be more economically worked. Some of the ore is manganiferou10. In a pit of Mr. Sparks' the ore is seen to pas.s clown beneath a clay horse.
The outlet of this basin is "Hematite" siding on the E. T., V. & G. Railway.

BROWN ORE IN THE VALLEY ADJACENT TO THE E. T., V. & G. RAILWAY.
On the east side of the valley a chain of ore-bearing ridges from Alabama enters Georgia at Etna, on the extensive property of CoL Hamilton. On the western side of the valley, except near Oredell, the hills are slaty and barren. The bottom of the valley ~s generally underlaid by Cambrian shales or slates, but the ridges to the east are composed of overlying decayed Knox dolomite,. partly brought iuto position by a fault. Along the western flank of the ridges there are subordinate ore banks.
On the State line there are extensive workings which have exposed the ore to a depth of 60 or 70 feet without reaching its bottom. As usual, it is a heterogeneous mass, but contains thick bedsof solid ore, as if disturbed by the falling of the roofs over limesinks. In fact, the true stratification of the Knox ore beds is gen-erally lost. The ore has a less concretionary and more massiveform than is generally seen farther east in other Knox deposits, and contains more or less included flint.
Northwestward of the Stateline, there are many extensive ore banks belonging to the Etna Company. The analyses of some of theEe

I'LATE VII I.

BRO'WN IRON ORES.

161

Dres will be given in the sequel. However, it may be noted here that considerable manganese is seen in various places, and that .sometimes the f r h working h w :lfj re cence of vitriol. Beyond Etna, similar .~,. , bauks o 'tu at. 1: ty r ' (Wood's, etc.) and Oredell, ,being ~mbordtna ridges of' red Ul'e-bcacing lands rising in the valley, or on its margin. In an artesian well snnk at Oredell the ore was found to continue to a depth of one hundred and eighty feet.
In a cut along th e railway the decayed formation shows much co nfnalo n bnt nppetLl' to d ip a val'ia bl aogl e~ u T. 15 W. and
th red po ita seem to belong to ouc horizo n. In n p'it nea t' l y,
t he Ol'C pass s under a whi t ln:y ll or 1 r 15 .11 t t.lJiut~, below whi<:b it wo 11 lcl hltr<lJy I?llY to wo rk.
The ridges, on the ea.~tern side of the valley, are to some extent characterized by accumulations of the usual type of ore, but there .are also other deposits of ore associated with the flinty or siliceous beds of the gray lands. Usually these deposits are infetior to those On detached ridges farther from the cherty beds.
All of these ore beds are convenient to the E. T., V. & G.
Railway. <U' h l' .tFlL'th upon the eastern si de uf th rnilwa b ~r w< t k-
.tlb] bed. of'ore are t0 und befbt' t' achw g tl1 Fl oyd Jiu ' ' hu., i i, >u ha tb ' whole cha.in of ridges boun ~ing tJh val-
l y 'II t f th East Tennessee, irg11na and or :ri}l ail wa fi:mlls a beJt of un.try d lt in ot 1i Ige.

BROWN ORES ALONG THE EAST AND WEST RAILROAD OF ALABAli{A,
Upon the western border of the Ordovipian or Lower Silurian ,slates, the Machuea limestones 'are valley making. Beyond these, many beds of iron-bearing Knox ridges occur. These form. th e great deposits of the Cedartown district. This belt enters Georgia at Esom Hill, near which place are the Brewster and other banks. At various points the ore banks reoccur, such as at Mr. Rice's, near .Berry station.
(11)

162

ECONOMIC RESOURCES.

The largest assemblage of ore banks is two or three miles south and west of Cedartown, amongst the chief of which are the Reed,. Ledbetter, Peek, Wood and other deposits, many of which are now included in the properties of the Augusta and the Central Mining Companies. Continuing onward, the ore appears at 1\fr. \Vaddell's and Mr. Frank Sheflets, two and a half miles north of Cedartown,. and on some other land~;. These ore banks rise from a few feet to fifty or one hundred feet above the valley. The ores are mostly small, concretionary lumps or masses, but with some greater blocks . or boulders. . In Peek's mine, ore has been seen approaching a bedding, and on au abandoned hill, ferruginous chert bluffs are seen. In all of these banks clay horses rise up and interrupt the pockets of ore (as represented in figure 22, page 155), but the ore has frequently a known depth of more than 40 feet. To one unfamiliar with the ore the first impressions are often disappointing,. as the value of the fine ore is greatly obscured in the clay.
Southeast of Cedartown these ore banks are not continuous throughout the belt. Two of the ore-bearing ridges rise up through overlying Chickamauga shales two miles south of Cedartown. Another iron-bearing locality occurs east of the shale basin south of Cedartown, near Young's mills, and at the Cleveland, Pittman, Cox and Ray hanks, between Young's and the metamorphic region to the south.
FISH CREEK DISTRICT.
A few miles to the eastward, ore beds of the Knox series are again hrou g ht t Lb sm1nce, ncar Fish cr ek. A Gra ly . l:at i n t\1 -re i an a elllbla of .hng o re bankf.! b lo ng ing to the ~ b e to k e Iro n 'oropany anrl to the C ntml .l\l[ioiug Jnn1paoy . 'l l.1 er ar large
-tn lejw it of t h u uo. l e with g reat. olay ( oft 11 w L..i.te) h .r. e. ,
ri sing intl>t he re a cUimuations. See ph1t i . thor ridges ext end southward a. at H.i 1-ma.n's a.ud 'imr>: on
miu (lo 1 l o, 21st d.istri t) W. 0. M urris' (1 ts lO c an.d 113 ) ;, anrl dl's. ~Io rgnn'. ~lU Ll MI.'. Win.n's ( l 1 6C, ':-. Lt ilistri t).



BROWN IRON ORES.

163

This belt continues, with interruptions, northward, to between one and two miles west of Seney and thence into Floyd county. Northward of Grady, on this belt, ore occurs on lands of T. H. Peek and adjacent properties; on several lots belonging to Mr. T. Colbert (as on lot 306, 21st district), B. F. vVest and others, thus showing the continuity of this belt across the country.
LONG DISTRICT.
Another belt is adjacent to the East Tennessee, Virginia and Georgia Railroad, between Rockmart and Seney, especially in the region of Long station. These deposits are on subordinate ridges on the western side of the valley of the Chickamauga series. From these beds large quantities of ore have been shipped, the principal mines being those of the Central Mining Company, the Randall and the Cochrane.
RECAPIT ULATION.
There are now well established six different belts of brown ore deposits, dependent upon the geological structure as described elsewhere. These are: ( 1) in the fault basin north of Indian mountaiu ;(2) t htl from Etuato a.v 'prin ; (') th Cedartown (4)
thaL,' uilien.s of 'edttrLo Wll; C'') the li'isb cr ek z n , (H) t he
L on r 11tation cli sbrict. T hor n1 ' ntly-ing d ~> . i s of 1 town t , e J iltl ly ~Ull \l n g th h rt ti<lges; UL(t h d 'posits ln t h b It described are those of most valne. In the survey of the belt, many peoperties were visited.
The belts having now been indicated with the modes of occurrence of the ore deposits, the primary object of the survey in the region is attained upon the publications of the report.
KNOX 0REfl IN FLOYD COUN'l' Y .
CAVE SPRING DISTRICT.
Entering Floyd county, the second belt of brown ore described in Polk county, continues northeastward, and with many breaks,

164

ECONOMIC RESOURCES.

extends across the country, amongst the Knox ridges eastward of Van's valley. These ores are, consequently, situated at no great distance from the' border of the Knox dolomite formation. This belt of country is more broken than in Polk county, with ridges of the cherty beds of the Knox se1ies, and consequently the1e are more repetitions of ore beds, although many are of inferior size. Then again, amongst the cherty riclges, the ore is frequently seen, with characters described elsewhere.
A few examples in the belt between Cave Spring and Rome may be given. Of the type of ore beds amougst the gray ridges and narrow rugged valleys, is the mine of Dr. Montgomery, north of Cave Spring (lot 620). This is on the eastern side of a steep ridge bounding the narrow valley. The ore is beneath rePidual beds of clay, dipping 10 S. E. The ore is very unequally developed.
The belt of Little Cedar cr.eek enters Floyd county, and there are extensive deposits on the pmperties of Major J. M. Couper. This continues onward, and adjacent to Cedar creek the features of the country are rounded, and there is a considerable number of ore bunks. Mr. J. W. Asbury's lot (950 ?), about two miles northeast of Cave Spring, has an extensive low ore bank situated in the valley. Near by, ore occurs on lands of Mr. Wiggins (lot 948 ), ou Mr. Simmons' (lots 923 and 924), and other properties.
Near the creek, on the farms of Mr. Roberts and Mr. J. R. Scott, ore occurs, but associated with much cherty soil.
In the district northeast of Cave Spring, near Six Mile Station on the border of the valley composed of Cambrian shales; there i& a subordinate ore-bearing ridge situated on farm of Mr. Gibson.
Passing near the western Knox ridges, ore is found in many places, and in some cases the deposits are large. At the foot of a ridge of gray land, there is a large development of brown ore, forming almost an inegular bed in Booboobollow, on lot 692, and adjacent properties.

BROWN IRON ORES.

165

Further south, on Cave Spring road, just hack of New Prospect church, a large outcropping bed of siliceous brown ore occurs.
On the top of the red ridge, hack of New Prospect church, brown ore (and also manganese) occurs. From a well, on this high ridge, it appears that only the surface is composed of red clay, and the cherty earth occurs beneath.
Again, the ore occurs 011 Mr. R. S. Brammon's la11d (lot 14, dis-
trict 22 ). Large deposits of ore occm 11ear Mr. J. A Howell's
beauxite beds, lot 610, 22d district. Indeed, .ore in limited quantities, is likely to he found in many
portions of the triangular area of the Knox formation, west of the East Tennessee, Virginia and Georgia Railway. The region is one characterized by gray ridges (sometimes red) and often narrow valleys, except alot~g Cedar creek, and the north western border of the formation.

SPRING AND SILVER CREEK DISTRICT,
Between Seney and Silver Creek (P. 0.) the valley is wider and less abrupt than west o'f this meridian. At less than two miles west of Seney, the roa 1 enters the Silver creek valley, which represents a belt of lower Knox ore-bearing lands, that extend southward to the banks of Grady. At about three miles from Seney (on Rome road), there is ore at several points, as on land of Mr. Vincent.
On nearing Silver Creek ( P. 0.) the valleys become broadPr, and
on ridges up to 50 or 80 feet in height, brown ore occurs at several places, as on the lands of Mr. W. C. Howell, two miles south of Silver creek. On the ridges east of Silver Creek ( P. 0.) the ore again occurs on Uoughly or Rich farm, and adjacent properties on road to Chulio.
From near this point a stream extends north, midway between Spring and Silver creeks. In this valley there are several large ore banks on the subordinate red ridges, as on the lands of Dr.

166

ECONOMIC RESOURCE S.

Boyd, Mr. C. Ivens, T. Cochrane, L. Mathews, S. Hoffman, and J. B. Alexander (lot 214, district 22). These l~tter are in gaps amongst the higher ridges, and show ore on extensive srirface ex.:. posures. The deposits may be considered in the same belt as those of the upper part of Silver creek. The valley of Spring creek forms another belt of ores. This zone is a continuation of that at Long's, in Polk county.
About two miles southeast of Seney, there are large ore banks belonging to Mr. Henry Wood (lot 194, district 22), and on adjacent property of Mr. G. C. Drummond.
Several deposits occur about Chulio, and are reported on lands of Mr. N. Wimper (lot 222, district 22), Mr. A. Johnson (lot 205, district 22), Mr. Lyons (north of Chulio), etc.
Again, there are deposits of large size east of Rounsaville, passing into Bartow county, in the report of which they will be described.
North of the Etowah river, near the northwestern border of the Knox series, ores occur in quantities.. On the Blackstock (about lot 186, 23d district) and other properties, the ore occurs in the red hills. In the northeastern corner of the county, adjacent to Armstrong mountain, there are many ore beds, some of which have been worked f9r the Ridge valley furnace, at Hermitage. Here the deposits are intermediate between the red and gray lands, or the purer and the more cherty ore beds.

RECAPITULATION.
In Floyd county, the ore belt of the Etna, Cave Spring and Cedartown district coalesce, but the country is broken np by the re- peated ridges, into a vast number of deposits, many of which are small properties. Also, there is a close proximity of those deposits, derived from the cherty dolomites (gray lands), and from the more earthy red lands.
The Fish creek belt continues northward into the upper part of

. ;

BROWN IRON ORES.

167

:Silver creek valley, and thence into another valley, midway between Rome and Spring creek.
The Spring creek zone commences in the Long district, in Polk county, passes east of Seney, and enters Bartow county, east of Rounsaville (or Bryant) P. 0.
North of the Etowah, the principal ore belt lies near the northwestern margin of the Knox series, aud extends to the Armstrong ,mountain.

KNOX ORES IN B.ARTOW COUNTY.
SPRING AND SILVER CREEK DISTRICTS.
The Spring creek belt of ores enters Bartow county southwest of Rounsaville. Extensive beds are found near Ligon (on Mr. R. L. Griffin's land, lot 426, 17th district, and many neighboring lots); .also on the farms of Mr. Z. T. Nichols, John Beck and Mr. C. Dodd. The quantity of the ore is large, and the conditions are similar to those at Cedartown.
At Mr. Nichols' house, in a well, the residual red clay extends to :.a depth of thirty feet, beneath which the earth was of lighter color but not cherty. These red hills form a chain of disconnected eminences trending east and west. Some small deposits of ore occur mortheast of Taylorsville.
TOM'S CREEK AND CONNESI~NN.A DISTRICT.
North of the Etowah river ore is again seen in the drainage valley of Tom's creek, as at Mr. Osborn Shaw's (about three miles from mouth of' creek). Here the ore is more or less bedded in an .excess of chert.
West of Lin wood, on the Barnsley estate, t.he ores again occur. West of Adairsville, ore is seen in the broken country on lands of Mr. J. J. Johnson (lots 108 and 109, 15th section), Mr. Cass Walters and others.
In the valley of the Connesenna brown ore occurs, as on lot of

168

E CONmiiC R ESOU RCE S.

Mr. Connaway (lot 116, 17th district). Here the soil is yellow

and the surface covered with some chert. Ore also occurs on land

of Mr. C. W. Waldrop (lot 136, 16th district). Ore is seen again

on lot (100, 16th district) of Mr. Robert Kerr. The ore is in

quantities on lots 52, 99, 8, 9 and other properties east of the

Connesenna valley.

In the upper part of Cedar creek, in northeast Bartow, small

quantities of brown ore occur on lot 55, 6th district, on Mrs..

Slaughter's land, and on adjaeent ridges, etc.

Near Rogers' station (on the W. & A. Ry.) some ores are seen.

..

In the valley of Petty's creek, about five miles north of Carters-

ville, brown ore covers some Knox ridges.

RECAPITULATION.
In the western part of the county, south of the Etowah river, brown ores occur, principally near the Floyd line. North of the river, the largest developments are adjacent to and moRtly west or the Western & Atlantie Railway. The country is broken by ridges, but these are continuations of belts from Polk and Floyd counties. There are a few localities of ores in the central part of the county where outliers cannot be correlated with the other belts, except that they are in the Knox dolomite series.
ORES OF THE ~IETAMORPHIC ROCKS.
The ores in the eastern part of Bartow are extensive, but belong to another group of rocks which have only been approached at a few points and not yet sufficiently surveyed to be reported on. The district is of great importance, as seen from the fact that one company alone shipped 30,000 tons of brown ore between October 1, 1890, and November, 1891.

THE ORES OF 1'HE Sun-CARBONIF ERous S ERIES.
The brown ores of this series ba\'e been referred to. They oc.,.. cur in Polk county on cherty ridges, associated with cherty beds_

BROWN IRON ORES.

16~

These are on Mr. West's and adjacent properties, about six miles south of Cedartown. Some of the deposits are rich in iron, but they are mostly massive. Similar, but poor deposits occur on ridges about Rockmart.

DEATON ORE SERIES.
These ores are found at only a few localities, northeast of Rockmart. The Deaton mine represents the principal working. This is situated near Taylorsville. A plate of the mine has already been given (frontispiece). The mine is on l.ots 81 and 64, 18th district. The Central Mining Company has similar deposits on and adjacent to lot 1076 of same district. The formation is found on lots 714 and 715 (Carlton's), 869, 870 and 932 (Haton's), and 868 (Jones'), all in the 18th distriet, most of which lots belong now to the Rockmart Development Company. These accumulations represent residual beds of the series resting upon the Chickamauga limestones, and at the edge of the hills of the Rockmart slates. Some of these banks rise to 100 feet above the valley. Their modes of occurrence are described elsewhere (pages 46 and 84). Other bank may yet be found. The workings at the Deaton bank are shown

FIGURll: 23.-Pian of Deaton Mino. Shaded portions show the gulleries of the ancient e!we, which became filled with ore by the fnlling of the roof of the ironlimestones. The enclosed white Rreas show natural pillnrs of limestone.
in the little map (figure 23). At the back part of the opening, the heterogeneous mass passes in to bedded ore, not interrupted by the

170

ECONOMIC RESOURCES.

limestone pillars shown in figure and frontispiece. Almost the entire mass is ore, with only a moderate amount of ferruginous clay. 'The favorable conditions of occurrence, and the situation directly upon the line of railway, permits of the loading of the ore at less .cost than any other ore in the State. The condition of .the ore is .already described. The depth reaches at least forty feet.
The beds at the Central Mining Company's property often show the ore passing into an ocherous clay. The other banks are not de-velope<'l.

,KNOX ORES IN GORDON, MURRAY, WHITFIELD, CATOOSA, CHATTOOGA, WALTON AND DADE COUNTIES.
IN GORDO:'< COUNTY .
The Knox ridges west of Adairsville extend as a wedge into Gordon county. These ridges diminish in size and die out. Amongst them there are iron ore deposits, but scarcely of importance. East of Adairsville the often ferruginous ridges extend into Gordon county, but die down into a gray rolling country, and most of the Characteristics disappear.
IN MURRAY COUNTY.
The Knox series in the Spring Place district gives rise to the deep red soil so characteristic of the iron ore beds, with some surface accumulations of ore. In this region closer search may find larger deposits of ore.
IN WHITFIELD COUNTY.
On the gray ridge west of Tunnel Hi~l valley, the residual clays in part give rise to reddish earths, and in part to very cherty land. In these red earths, pockets of brown ore are ocrasionally found.
IN CATOOSA, CHATTOOGA, WALKER AND DADE COUNTIES.
In the cherty ridge of Knox series extending from near Tunnel

BROWN IRON ORES.

171

Hill northward, brown ore is frequently met with. It is more or less associated with cherty beds. In ~be belt of the same formation, west of Rocky Face, it also recurs northeast of Holland, and thence northward there are accumulations of ore in the Knox dolomite series. Also on the ridges west of Summerville. Indeed, wherever, the Knox formation occurs, there are apt to be some deposits of brown ore. In this section of Georgia, the cherty portions of the series prevail, with a consequent inferior development of ore as compared with the red lands of the same series east of the Coosa nver.
THE DEATON ORE SERIES.
The Deaton Ore series may be represented in the ferruginous rocks extending from eastward of Varnell to l!be Tennessee line. They are associated with deep red colored lands and ferruginous limestones. The ore is unlike any other in the belt surveyed, being a pseudo-specular ore with smooth surface and submetallic luster. The deposits are more or less bedded, except \vhere such are broken. These deposits are seen not only at the Catoosa (?) Company's property, a mile and a half from Varnell, but also near Red Clay, on the land of Mr. W. K. Sheddon.
Sun-CARBONIFERous OREs.
,Sub-Carboniferous brown ores occur in large quantities in the extreme southeastern part of Walker county upon the eastern flanks of Horn's mountain. These deposits extend into Gordon county, west of Sugar Valley. The beds have already been taken as a type (page 157) of Sub-Carboniferous brown ores. At that locality they ha,Te been extensively worked. The same ores also occur upon the western side of Big Texas valley, Similar ore is seen at many points where the Fort Payne chert comes to the surface, as on Fox ridge; still few diggings have exposed the occasional developments. As an ore-hearing formation, this series is less important than the Knox, the cherty members of which it often resembles.

172

ECONOM:fC RESOURCES.

CHAPTER XXIII.

THE COMPOSITION OF THE BROWN ORES.

MODES Oll' WORKINO '!'HE ORESj FURNACES, ETC.

ANALYSE:l.

The workable boulders of brown ore do not generally contain

less than fifty per cent. of the metallic iron. The beds of cherty

ore, so often associated with the gray ridges, are usually too high in

siJicaforprofitableworking,on account of diminishing the petcentage

of iron and the additional cost of fluxing and reduetion.

The quantity of the phosphorus is variable. In some cases the

phosphorus is very low, but again it is sufficiently large to prevent

its use, although this is not generally the case.

Manganese is present in some ore banks to an appreciable quan-

tity. Zinc is occasionally found. A curious product was accumu-

lated beneath the funnel of a charcoal furnace (Chet"Okee of Cedar-

town), and when the furnace was blown out in 1880, about ten tons

of the following prod nets were obtained:

Zinc oxide -------- . - - -- -- __ ,.__ ______

Per cent.
_ ____ 83.44:3

Alumina and iron _____ ,

---- . _

3.700

Coal dust -- - _----------- -------

3.140

Alkalies (by difference) ____ _ . __ ----- ________ _. _. ___ 9.857

Sulphur . __ ___ _ _ __ - __ -- -- ____ -- _____ .. 0.203

Cadmium oxide ......... ___ ___ ------------- - - ---- Trace

Insoluble matter . ____ ------------ ------- ----- - _ 0.600

The variations in the composition of the ores of the Knox series

is shown from analyses for the Cherokee Iron Company by

Ernst. Sjosted, chemist:

BROWN IRON ORES.

173

CEDARTOWN AND FISH CREEK ORES.

ISAriolluincmasi.en..saq. .u.i..o'.x...id..e..........,.............
Lime ..... . . .. ...... .. Magnesia .... . .. ..
'MPVhaaontsPgprah.no.e.rs.iec..A..c.i.d..............................
Iron, metallic .... , ... . . Manganese . . . Pho~phorus . .

I. 8.01 13.21 70.57 1.27 0.42
0.12 0.58 5.01
41:.1.40 0 .09 0 253

IL 15.95 17.01 57.00 1.13 0.22 0.93 2.] 7 4.88
39.1:.10 0.72 0.949

III. 9 . 27 41.48 78.85 1.61 0.48 0.40 0 91 4.20
55.00 0 31 0.399

IV. 12 .18 5 . 52 71 28 2 .99 0 .50 0 .27 1.11 6 . 08
49.9 0 22 0.491

v.
10.60 371 80.J4 1.49 0.11 0.38 0.88 3.08
56.1 0 22 0.386

T\TL T
10 .19 6 . 81) 75 .14 2 41 0 41 0 .35 1.00 3 51
52 .6 0 .27 0 438

No. 1. Roasted ore from the Grady Bank. II. Roasted ore from Peek's Bank. III., V., VI., ores nsed on three succeeding days in furnaces. IV. washed ore.
The iron ores, being variable, yield metallic .iron, containing from 0.20 to 0. 75 per cent. of phosphorus.

ETNA ORES.

A number of analyses of the Etna ores was furnished by Colonel Hamilton. Of these, one complete analysis may be given:

Per Ceot.

Iron sesquioxirle...

.. .. .. .. . .. .. . .. . . .. .. .... .. . 81.26

Manganese se~quioxide .. . ..

.. .. . . .. .. . .. .. . .. .. . ..

0 . 43

Alumina . . . . . . . . . . . . . . . . .

. . , , , , . . . . . . . . . . , . . . . . . . . . . . 1.12

Lime... . . . . . . . . . . . . . . . . . . . . ... . .. . ... ... . . . . . . . .. .... . .. . . . . t\.12

bilica .. ..

.. . . .. .. .. . . ............ ,

5. 79

Water .. . .. . . . .. . .. .. . .. . .. . .. .. .

.. . _...... .. , . . .. .. 11.45

Phosphorus. . .. .. .. .. .. .. . .. .. .. .. .. .. .. .. . .. . .. . .. .. .. .. .. 0 .05

onlphur ... . .. .. .. .. . ..

.. .. . . .. .. . . 0.01

Metallic iron . . . . . . , .

100.23 5(i 88

The analyses of the ores obtained at eleven other ore banks gave the average yield :

Per Cent.

Metallic iron..... .... ......... . . .. .. ....... .. .. from 58.45 to 51.10

l'l.~e.tallic manganese .. .. .. . .. .

.. . . .. .. . .. . .. from 0. 20 to 5 60

Silica........ ..

.............. .... . ........ from 2.40 to 7.87

PhosphoruE> .. .. .. .. .. .

. .. .. .. from 0.147 to 0 858

One analysis showed 16.39 per cent. of silica. Another anslysis gave 1.396 per cent. of phosphorus. The-above analyses were

174

ECONOMIC RESOURCES.

made in the laboratory of Messrs. Cooper & Hewitt, Reegelsville, Pennsylvania.
The analysis of the iron produced in May, 1890, showed the presence of:

Silica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0. 253 Manganese. . ... . . . ....... . . .. .......... , . . . . .. ......... . . . 0.144 Phosphorus . . ............. . .. . ......... ... ..... . ....... . .. 0.412
Sulphur. ..... ..... .. ...... ... ............ . , . . .............. 0.000

0. 337 0.124 0.393
0.000

The character of the ore, as ready for shipment, differs from that in the beds only in concentration.

THE ANALYSIS OF THE ORES. FROM THE DB:ATON (COUPER) MINES.

I.
Metallic iron.. . . . . . . . . . . . . . . . . . ... , ... . 48.56 Silica . . . . . . . ... , . , . . . . .. ..... . . ... . 14 .25 Phosphorus . . . . . . . . . . . , . , .. , .. . .. .. . . 0 .363 S~1lp~ur . ... . .. . , , .. ... , . ........ , . . .. . Trace. T1tamum .. .. ........................ . 0.011 vVater .... . .... . .... .. .. . . .... . ...... 1.30 Lime ... ... . . . .. . ..... . ..... . . ... .. . ..... . Alumina . . ... ... ... ... ...... . . . . . . ..

II. 49.32 11.04 0 .335
. 2 . 53 0.73

III. 49.80 12 .03 0.287
Trace. 9.0-!

One individual analysis gave iron only 33.12 per cent., and others showed the phosphorus below 0.3 per cent.

MODE OF WORKING THE ORE BANK~.
Until comparative~y recently, the ore was simply dug out of th e banks and screened, thereby losing a large portion of the best ore. The product was thus concentrated to nearly 50 per cent. of metallic iron. In some cases, the ore was roasted before use, whereby further impurities, as adhering clay, were removed.
Washing of the ore is not adopted in the small er workings, but this method is much more costly than where the pay dirt is washed, not only on account of greater cost of labor, but also because of th e smaller product. Under such conditions the richer deposits can only be worked. Now a great change has been brought about by the use of screw washers, whereby ferruginous earth with only a small

BROWN IRON ORES.

17 f).

per cent. of iron concretions cau be concentrated and sent cheaply into the market, with composition as given above. In a few cases,. the cost is further reduced by the use of steam shovels. Under the former system it frequently costs a dollar a ton for raising the ore_ At the Deaton mine, the ore can be put on the cars at less than fifty cents a ton.
The plant for washing costs $2,500 and upwards. But in the larger pits this has now become necessaty. Still, even during the summer of 1891, many small pits were being worked, and the ore transported by wagons, three miles or more, to the railways.
THE ORE PRODUCT.
In 1890, the brown ores derived from the Knox series amounted to about 200,000 tons, shipped outside of the State. Besides this quantity, about 60,000 tons were consumed in furnaces in the districts.
vVhilst railway facilities are close at hand for the shipment from. many districts, yet there are many others too distant to be, as yet, in the market.
OCHRE WORKS.
Recently ochre works have been established at Rockmart for the manufacture of paint from the ferruginous clays in that district.
At Cartersville, an establishment has been in operation for someyears. The ocherous clay is not then obtained from the Knox series,. but from decayed, metamorphic rocks south of the town. Hencefurther notice will be postponed for a future report.

176

ECONOMIC RESOURCES.

CHAPTER XXIV.
RED IRON OR "FOSSIL" ORE .
CONTENT.~.
HEMA'l'l'l' E "FossiL" ORE. liioDES OF OccuRRENCE.
HEMATITE.
Hematite has a hardness of 5.5 to G..J; specific gravity 4.5 to 5.3. "\Vhen crystalline, the luster is metallic, but it also occurs in an "earthy form. The color of the earthy form is red, with a cherry red or reddish brown streak. When crystalline, the color is steel grey or iron black. The fos,il ore belongs to the red variety, although it often contains small concretionary particles, having a steel grey or iron black luster. Hematite is the sesquioxide of iron, and, when pure, contains 70 per cent. of metallic iron and .30 per cent. of oxygen. Hematite, especially the earthy -varieties, arises from the dehydration of limonite, which itself may be formed from the decomposition of the carbonate or sulphide of Iron.
THE FOSSIL ORE.
Fossil ore is essentially hematite-of the earthy variety, and is a mineral of secondary origin; in short, it is a limestone converted into iron ore, and contains the impurities of the original limestone. Above the drainage level, the calcareous matter has been completely removed, leaving the ore in a concentrated state, but containing more or less sand and clay as impurities. Below the drainage level the calcareous matter still remains, to a greater or less extent;

FOSSIL ORES.

177

or, in other words, the ore bed is a ferrnginou'J limestone, containing from 10 to 25 or 30 per cent. of iron. The structure of the ore is essentially that of a mass of broken shells intermingled with small flattened nodules. This form is best seen in the ore above the drainage levels, from which the calcareous matter has been removed. The ore at greater depths approaches a massive, granular structure. This more compact mineral is known as "hard ore," whilst that above the drainage level, which is richer in iton, is designated the" soft ore." Owing to the concentration of the iron by the removal of the calcareous matter, the soft ore may contain iron to the extent of .50 per cent. or more. The change from the soft ore to the hard ore is sometimes gradual, but at other times sudden, with thP. lower portion of the same outcrop much harder and more compact than the upper bed.
The source of the ore appears to be the ferruginous shales, in which the ferruginous limestones are interbedded, and which have been, in part, converted into ore beds, owing to the percolation of rain waters, and the deposition of the iron into the ;)ssil beds, and the simultar1eous removal of an equivalent amount of calcareous matter. The exact process, however, i-; not known; but from the structure and preservation of the forms of the shells it is manifest that the greater part of the ferrugination took place subsequent to the formation of the limestones.

:VIODES OF OCCURRENCE .
The fossil ore beds in Georgia are entirely confined to the Red Mountain series, which is part of the Silurian system. This ore bearing horizon is commonly correlated with the Clinton beds of New York, although the typical subdivisions are not sharply defined in the southern Appalachian region. The thickness of this formation in Georgia, as noted elsewhere, reaches 1,100 feet. Whilst a portion of the formation, especially the eastern outcrops, contains massive saiHlstones, yet in the richer portion of the series
(10)

178

ECONO.MIC RESOURCES.

almost the entire succession of beds is made up of shales with occasional :-;andy flags; indeed, the fossil ore bed has often the form of ferruginous flagstones. The ore beds vary in thickness from 10 inches (or sometimes less) to as much as 7 feet, although thicker, in places in Alabama. The common thickness, however, is from 20 to 36 inches. It is sometimes in one solid bed, or divided into two or more layers, and, occafoiionally the layers are separated by laminations of shales; thus considerable variation is produced, although the continuity of the beds is remarkably constant. The ore appears to occur somewhat abo\'e the medial horizon of the Red Mountain serif.s, and in a hotizon higher and newer than the heavy sandstones, such as are found in Taylor's ridge and eastward.
vVhilst the Red mountain beds commonly lie at angles of 20 or 30 or less, yet the formation is folded and distorted to a very great degree, so that the beds sometimes clip at as mucl,1 as 80. Thit-~ folding, or undulation, sometimes gives rise to a superficial appearance of a duplicate set of beds, as shown in figure 24. At this point

FIGGRE 24.-At Wessboro mines. Folding and faulting (F) ofbecls. Ore bed (0).
not merely are the undulations seen, but also r:;harp faults. vVhilst the Reel Mountain ridges rise up to form bold mountainr;
in Taylor's ridge and eastward,-owing to the protective cappings of sandstone rock, yet the Red Mountain ridges which skirt Pigeon and Lookout mountains contain no hea\')' beds of sandstone, and thus the features are not so strongly marked across the country; but in many places, these foothills, composed of the ore formation, have been protected by interrupted cappings of F~rtJPayne chert, which

FOSSIL ORES.

179

ba ve preserved the ridges and left a serrated chain of hills, rising two to three hundred feet above the valleys, as shown in plate IX. Upon these ridges, where not obscured by the chert, loose rectangular blocks of the fossil ore often mark the occurrence of neigh boring bedl:l of iron ores. However, the iron ore is commonly obscmed by the covering of disintegrated red shales. 'Vhere the capping of chert is iuterrupted, the ridges are iutersected by tramoverse depressions, which sometimes cut the ore beds in two, and expose their outcrops in the gullies, thus causing the continuity of the ore to be interrupted at the surface. At greater depths, however, these interruptions probably are of rare occurrence; and the or.e extends downward forming sheets beneath the drainage level. Above the drainage level the shales are e\erywhere decayed, thus leaving the roof.<; of the mines in weak condition, although they become stronger the farther they recede from the surface, but below the drainage level, adjacent to the harder ores, the rocks become com pact. In many localities the ore has a preservative effect upon the hills, and is found near the surface, and more or less parallel with the hillslope. In such cases, the overlying shales are quarried oft~ without any attempt at mining, and the limit of such removal does not usually exceed 15 feet; but the ore is often taken out from beneath the shales by mining processes, as shown in plate IX.
'Vhilst the ore beds, in some places, arc situated in the upper part of the Red Mountain series, yet the horizon is not fixed but somewhat variable. In many cases, there is only one bed; yet, in others this is lwoken up into two or more layers with shaly partings. vVhen these shaly layers are thin, they do not prevent the mining of the ore; but in places, they become thick and then the amount of ore in the indiddnal beds is insufficient to pay for the .removal of the intervening rock. In some cases, the ore becomes shaly or sandy, and is too poor for working.
In the Red Mount~in series, the shales above the drainage level are mostly red, although greenish or bluish where not weathered.

180

ECONO.MIC RESOURCES.

Also there are occasional layers of limestone, which have escaped ferrugination. Some of the shales become very sandy flagstones, and contain a large percentage of iron, but not sufficient for economic purposes. Indeed, the amount of iron in the worka-
ble beds is only a small percentage of the metal in the Red Moun-
tain series. Below the drainage level, besides the ore beds, there are other layers of limestone, which have not been ferruginated. Sometimes the soft ore, near the surfaces, graduates into hard ore, below which again it becomes soft, owing to the admission of percolating waters, due to fracture and local faulting. The hard ore, below the drainage level has also a greater thi:ckness than the soft ore at the surface.

FOSSIL ORES.

181

CHAPTER XXV.
LOCAL DISTRIBUTION OF FOSSIL ORE.
CO;:i!TENTS.
DIR'l' SELLER 1\-IOUNTAIN, SHINBONE RIDGE. LooKOUT MouNTAIN. TAYLOR'S AND DICK'S RIDGE,
DIRT SELLER MOUNTAIN.
This is a synclinal plateau entering the county from Afabama. Its surface is somewhat undulating, owing to unequal atmospheric erosion. This table-land rises 600 feet above the valley or 1,400 to 1,500 feet above the sea. This is the only table-land built out of the Red Mountain series, which usually gives rise to narrow steel) ridges. The strata lie at low angles and the fossil ore layer commonly occurs near the top of the series, still remaining covered with only a few feet of shales. where seen, it is composed of the rich "soft ore" variety. The ore bed is covered with disintegrated shale, which has been removed in workings, for the extractioJJ of the ore. Mining operations have not .been carried far underground. To the northern end of the mountain a branch railway has been constructed from Lyerly.
SHINBONE RIDGE.
Skirting Pigeon aud Lookout table-lands, as well as the eastern side of Sand mountain, the serrated ridges of the Red Mountain series noted elsewhere form prominent features, as shown in plate V., page 48.
These narrow ridges rise from 100 to 300 feet above the valley.

182

ECON0111IC REtlOU.RCES.

In some localities, the preservation of the ridges is due to the ore beds, but the higher points usually owe their preservation to the remains of the Fort Payne chert series. Entering the State from Alabama, the first mines occur at Menlo, where the ore bed is divided into layers of nearly eqnal thickness, the whole varying from two to three feet. The upper layers are composed of soft ore.
The strata dip at 20 N. 50 vV. and the m~e lies near the surface
of the ridge upon its western side. Between this ridge and Pigeon mountain, there is a narrow valley. A short distance from the exposures noted, where the strata clip, at comparatively low angles, the ore beds are found dipping at 75; and at one point the local synclinal was noted. The red ore continues northward throughout Shinbone ridge, and dips under the mountain to the west. These ore bearing ridges are, however, interrupted by occasional ravines.
At Btonco, the hard ore is being worked by a shaft over 200 feet deep. Adjacent to the foot of the shaft, the strata dip 80 N. 80 W. .At this locality, the disturbance'> are great. On the eastern edge of the ridge, the dip is eastward; thence the strata pass into an overthrow at the mines, ~nd afterwards Hatten out beneath the plateau of Lookout mountain to the west. As this mine goes below the drainage level, the soft ore gmduates into the hard variety. The former averages about 55 per cent. of metallic iron,
whilst the hard ore contains from -o per cent. downwards (see
Composition of the Ores). The ore bed varies from three to three and a half feet, and lies in variable positions, owing to the physical disturbances. At a depth in the mine, several beds of nnferruginated limestone occur. Although these are compact, yet they are more or less impure, and their weathered remains at the surface produce some of the red flaggy layers, which are of common occurrence at some horiz,Jns in the shale.
The best exposed section of the Red Monntain shales is seen along the railway cut at Dug Gap, which crosses the end of Pigeon

FOSSIL OREB.

183

mountain. It is shown along horizontal exposures, where the average dip is 8 eastward.
Feet

Red laminated shales. -- --- --------------------- 510

Brown shales ___ _ --------------

180

Shales with numerous layers of flaggy sands!one, including

some bands rich in iron, at a point 1,170 feet from the

western end of section ______ - - ------- ... _ .. _______ 600

Reddish laminated shales . ------ _

-- - -- __1,140

Shales with hard flag-stones.- --------------------- 180 Laminated shales.. ____ ___ ____ __- . _ . ___- _. - -- __... ----. 270

Shales with thin flag-stones

_____ _ _____ .. __ .. ___ 720

Hard red sandstones (14 inches thick) and shale beds with iron ote separated into thin seams __ ___ _ _____ __ _ _ 90
Hard sandstone.'>, shales and flag-stones ___ ______ .___ __ __ 450

Shales and flags with 2 feet of ore s_eparated into layers by

thin shales ____ ,_ ____

- ------ - ------- _ 90

Red and brown laminated shales __ ____ .. ------- -- ----- - 480

Ditto, with occasional flag-stones ___ __ . __. _ _____ . _1,280

Hard blue shales passing into red laminated shales, with some

flag-;,tones ___ ____________ ---- - -- ---- _ __

_ 960

Devonian shales at western end of tunnel. __ _____ ___ _

The longitudinal section reduced to vertical thickness gives 1,100 feet as the total depth of the Red Mountain series.
The ore formation gives rise to ridges about the northern end of Pigeon mountain. Again, it skirts both sides of the anticlinal valley of McLamore's Cove, and is seen on the property of Mr. Dougherty and Mr. Clarkson at the head of the cove, where the exposed ore beds have a thickness of from 6 to 18 inches. The ore beds are commonly more or less covered with shaly soil, and the full extent of the deposits is not known, owing to the few natural exposures. These ore belts continue n'orthward, along the eastern side of Lookout mountain, almost to the Tennes'>ee line.

184

ECONOllliC RESOURCEf-l.

Along the Chickamauga and Round mountain railway, there is a longitudinal.section across the series, having a length of about half a mile. In this section, there are fewer flaggy beds than at Dug Gap, just described. At this locality the shales are more massive and less laminated than to the eastward; The strata dip at 20 N. 70 \V. with some local disturbances.
A short distance south of the railway just mentioned, the W essboro mines are in operation. The position of the ore beds is similar to that just mentioned, but with local disturbances produced ft'om faults and changes of dip, vatying from 20 to 70, as shown in figure 24.
Here the soft ore, in the hillsides, has a thickness of 2 feet. The covering of the ore is removed until the limits of profitable working is reached, beyond which the shales are undercut for short distances, as shown in plate IX. But deep mining ia not continued far into the hillsides.
East of High Cliff Postoffice, there is a separate basin of the fossil ore series, bounding an anticlinal valley. The ore where seen occurs in red shale, and has a thickness of only from 6 to 10 inches, but there may be other localities where it is thicker.

IN LOOKOUT VAI,LEY.
The Reel Mountain series forms a chain of serrated hills (see plate V., page 48) skirting both sides of Lookout anticlinal Yalley, that is, both dip from the valley and pass under the two mountains on either side. Near the Alabama-Georgia line, as also near the Tennessee State line, the beds unite and cover the lower anticlinal formation.
Throughout the series in Lookout ,alley, the ore is generally met with, although interrupted by ravines crossing the ridges. In many places the soft surface ore has been extracted to as great a depth as would be permitted by the system of removing superincumbent earth. (See plate IX.)

PLATE IX.

FOSSIL ORES.

185

Underground muung has not been resorted to except at Rising Fawn. On the ridges about the furnace, most of the superficial soft ore has been exhausted, but the hard ore passes down at low angles beneath Lookout mountain. The total thickness of the hard ore beds reaches 7 feet. Only in one locality, on Pudding ridge, north of Rising Fawn, is the surface ore as thick as 7 feet ; even here the principal layer is only 3 feet, with the remaining 4 feet interbedded amongst shaly seams. Throughout the ridge the soft ore is generally from 20 inches to 3 feet in thickness. In a boring at Rising Fawn, Mr. Eleven found the hard ore 7 feet thick at a depth of 80 feet. Throughout the whole valley there are many workings in the foot ridges beneath the table-lands. The soft ore east of New England City has a thickness of about 2 feet, and is largely used for the manufacture of rE>d ochre.

TAYLOR'S AND DICK'S RIDGES.
Near the Alabama line a limited amount of ore is seeu in the easteru side of Kincade or Simms' mountain (a part of Taylor's ridge). Some ferruginous sandstones ocrur at Kitchen's gap, east of Holland. At High Point, the ridge has been pt'eserved, owing to the presence of heavy bedded sandstones. On the land of Mr.
Sculett, where the rocks dip 60 N. 30 vV., on the eastern ridge of
a synclinal fold, fragments of fossil ore are found over the sandstones. At various points to the northward, the ore is also seen. In one place it is said to be 34 inches thick. Nearly east of Summerville Mr. Cleghorn owns an ore bed 'from 16 to 20 inches thick; this is of a good quality. It dips 26 S. 40 E., and is somewhat steeper than the easteru face of the mountain, ftom the summit of which the ore descends in the form of a mantle, thinly covered with shales, which have been removed by washouts in several localities, thus exposing the ore in the ravines.
At various points throughout the ridge the ore is exposed. On the Greenbush-Lafayette road, the ore is seen upon the eastern

186

ECONOMIC RESOURCES.

siCle of the mountain and in ravines, where it has a thickness of 12 inches. Taylor's ridge and Dick's ridge together form a synclinal basin, with rocks of the latter ridge dipping 80 N. 60 W. at Wood's gap. In Dick's ridge, to the northward on Mr. Hamilton's land, the ore is from 10 to 12 inches thick. At no point north of this place is the ore known to be thicker. Ore blocks also occur on Dick's ridge at G:ordon Spring, and also near Ringgold.' On White Oak mountain, a continuation of Taylor't> ridge, no important ore is seen. On the ridge above vVest Armuchee creek, near Subligna, the ore outcrops on Mr. Simms' land.
The ore horizon of Taylor's ridge is above the massive sandstones of the Red Mountain serie:->, and consequently, has suffered from atmospheric degradation, which has been carried so far as to remove t~e valuable ore from Horn's, Rocky Face and John's mountains, the strata of which reach to the horizon of the fossil .ore scnes.

FOSSIL ORBS.

187

CHAPTER XXVI.

COMPOSITION OJ!' FOSSIL ORE.

A:<ALYSES.

The soft ore is rich in iron. Its commercial value depends also upon the quantity of silica and of phosphorus present. Examples of the analysis of the iron from Shinebone ridge have been furnished me by Mr. Beuk. One of these analyses show: Metallic iron ____ __ --- - -- ---- --- -- __ - ______ ___ 60.72

Silica .... ------ -------- ------ ------- - - -- ----- ----- 8.28 Phosphorus ______ _ ------ __ -- ---------. ____ .J31
Besides these components, there were small quantities of alumina and lime. This analysis, however, is above the average in quality, both [l.S to the percentage of iron and the low amount of phosphorus, which is usually higher in quantity j however, the soft ores eommonly contain 50 per cent. and upwards of metallic iron. Such high quality of ore as that just given is often used for the manufacture of red ochres. Sometimes the hard ore contains 40 per cent. or more of metallic iron, whilst again, in the deeper workings, the metal commonly diminishes to 25 or 30 per cent. Of the better quality of the hard ore the following analyses were made for the Dayton Coal and Iron Company, and were furnished by Mr. Beuk. The ores were taken from the Bronco Mines on Shinbone Ridge, and the analyses were made by Dr. Gust. Bidtel. Metallic iron. __ ___ ___ ______ ___ __ _____ 40.65 41.30 45.32

Silica ----------------------- - _ 6.30 Alumina ... _______ ________ . __ ----- _ ___ 7.00
Lime ____ ----- - - --- - -- - - -- __ .21.00 Phosphorus -- ------- ----- -- ------ 0.42

6.10 13.67
18.64 13.62 03.51 09.58

188

ECONOMIC RESOURCES.

The lime is given as oxide of calcium, not as the carbonate. Many of the hard ores are self-fluxing. In the poorer ores the silica increases to 20 per cent. or more.
The following are some of the analyses make by Dr. Gustave Bidtel, for the Dade Coal and Iron Company, and fnrnishea by Mr. Julius Brown.

ANALYSES OF R[SING FAWN HARD ORE.

Iron.
30.38 28.3.4 24.13 22.46 27.81 26.28 30.39 27.79 32.19 31.10 28.91 29.41 31.08 29.87

Insoluble Residue.
8.21 10.64
8.91 9.56 11..36 9.35 9.76 8.65 !:! .22 11.67 8.46 9.71 15.16 8.07

Cnnstic Lime.
26.79 25.71 30.48 30.79 25.56 28.39 23.56 26.87 23.04 22.44 28.62 27.43 24.64 26.88

Phos]lhorns.
.3:31 .289 .269 .337 .270 .268 .368 .285 .304 .308 .322 .338 .274 .304

ANALYSIS OF RISING ]'AWN SOFT 0RH:.

, 'il icn ___ - _ Metallic iron Phosphorus __

- -- -- ~- .-- -- u.1'1
- ~ - -. -- 59.00
----- --- - . 92

FURNACES.

189

CHAPTER XXVII.
THE IRON FURNACES.
At Cedartown, the Cherokee Iron Company has, for more than twenty years, had a furnace with capacity" of 20,000 tons a year. It was originally a charcoal furnace, but coke is now used. Its product is a high grade of iron.
At Etna, there is a charcoal furnace of 10,000 tons capacity per annum, and making a high grade of car-wheel iron.
At Rome, a large new Coke furnace :went into blast in 1891, using red ore along with brown ores. Its capacity is about 20,000 tons a year. In April, 1892, they commenced making charcoal iron, using a large proportion of brown ores from Cedartown district, and a small proportion of red ore from Dirt Seller mountain. At Ridge valley, or Hermitage, another r.:.odern furnace is located, bnt it has not been in blast for some years.
At Rising Fawn, the Dade Coal and Iron Company have a furnace of 85 tons capacity per day. The ore is partly obtained at this point, but much is shipped to it from other points. The limestone is from the foot of the mountain near the furnace.
Dotted over the country there are the remains of several old, small furnaces, which have now no other than historic interest, m:uking the early efforts of local production of iron.

190

ECONOMIC RESOURCES.

CHAPTER XXVIII.
MANGANESE.
CON'l'EN'l'S.
UsES OE MANGANESE. KINDS OF ORE: Pyrolusite, Braunite, Psilomelane, Mauganite, ~Wad. MANGANESE ORES OF 1'HE KNOX SERUS IN GEORGIA. Co~IPOSITION OF THE ORES. MoDES OF OccuRRENCE.
USES OF MANGANESE.
The uses of manganese in the arts are not so popularly known as those of iron, and, indeed, many people upon whose property it occurs have very little idea of the extensive applications of compounds of this metal.
The largest demand is for the manufacture of spiegeleisen and ferro-manganese, which are alloys of iron and manganese; of certain bronzes; of chlorine, for bleaching purposes ; in decolorizing glass; in coloring glass, pottery and brick, and a variety of smaller applications. By far the largest quantity is used for the two first named products. These are used in the manufacture of Bessemer steel and other iron manufactures. It not only renders the metal hard but indirectly improves the produ~t and gi ve.'l valuable properties in a number of ways-such as reduction of oxides of iron fonned in steel m~nufacture; the increasing of the power of carbon to combine with iron at high temperature, and the preventing of its separation as graphite at low temperatmes, etc. For many purposes its value is recognized; and steel rails now commonly contain from 0..5 to 1.5 per cent. of metallic manganese.

MANGANESE.

191

The demand for manganese ores is constantly increasing. In the United States the product between 1837 and 1879 did not amount to more than 50,000 tons, of which 19,950 tons were obtained in Georgia between 1866 and 1879.* The total output. of the ores in 1880 were 5,761 tons, of which the Georgia yield was 1,800 tons. The consumption has rapidly increased, as shown by the following table of the product for. the whole country :

S1' ATES .

1888. To us

The greater part of the Georgia shipment was made from the Cartersville district, but in 1890-'91 over 3,000 tons were shipped from Cave Spring district, whence a few hundred tons were previously shipped. Besides these manganese ores, a large quantity of rich manganiferous iron ores are used by which the production of manganese compounds is largely increased.
KlNDS OF ORES.
Economically, only the oxides of manganese are of any value to us in Georgia, and of these the characteristics may be given :
Py1olusite m Peroxide of Manganese.-It is a soft mineral, having a hardness of 2-2.5, and specific gravity of 4.8. It has an iron black color with a black powder. It is commonly a crystalline mineral, and when crystallized is orthorhombic, and is often needle-shaped or fibrous. It has a metallic luster, and even when granular massive, it has often a glittering appearance. In composition it is dioxide of manganese, and theoretically contains 63.3 per cent. of manganese and 36.7 of oxygen. It often occurs in crystalline forms lining cavities or as incrustations.
: Minerul Reonrces of the United States, 1988, p. 1l5.

192

ECONOUIC RESOURCES.

Psilomelane iH a heavy mineral of 5-6 degrees of hardness. Specific gravity is 4-4.4. It is black or steel blue. The form is commonly botryoidal (like bunches of grapes); stalactitic or in irregular shaped ma::~ses. when freshly broken it has often a bluish, glossy, sub-metallic luster. In composition psilomelane varies, being largely peroxide of, manganese, with more or less water. It also contains a variable amount of baryta ftom a trace to 17 per cent., and potash to the extent of 4 per cent. Thus the manganese in the ore varies, when freed from clayey matter, from 45 to 60 per cent. of the metal. with this mineral, pyrolusite and braunite are commonly associated.
Bnmnite is a mineral whose hardness il-l 6-6.5, and specific gravity 4.8. It occurs both massive and crystalline, of black or lJrowoish black color, and dark brown powder. Luster is submetallic. It may be regarded as an anhydrous sesquioxide of manganese, containing silica. When pure it contains 69 per cent. of metallic manganese.
.Ma?iganite.-This is a mineral of medium hardness, hardness being 4-4.5; the specific gravity is 4.3-4.4. It crystallizes in orthorhombic prisms. It is also crystalline massive. Its color is black with a black or brown powder. Luster is metallic. It is a sesquioxide of manganese with watet; and when pure, the composition is manganese 62.5, oxygen 27.3, water 10.2 per cent. Upon loss of its 'Yater the mineral changes to pyrolusite, braunite, etc.
Wad m Bog.J1anganese.-This is a light, earthy brown or black ore, and is essentially an impnre peroxide of manganese, containing from 15 to 45 per cent. of the metal.

THE MANGANESE ORES OF THE KNOX DOLOMITE SERIES OF GEORGIA.
The principal ore is psilumelane, although commingled with it, mote or less of all ihe above named oxides probably occur.
The psilomelane occur.~ in inegular or concretionary masses, and is more or less kidney-shaped or botryoidal. The masses are often

MANGANESE.

19~

porous. The surfaces are usually covered with the powder, but when freshly broken they are conchoidal and show the steel-blue color. In some portions of the deposits, especially at a depth, the mineral is blacker and more crystalline, probably from admixture of braunite. In other cases the interior of the masses contains, or is interlaminated with, pyrolusite, or the surface is coated with it. These manganese ores occur in detached masses from the smallest particles to a ton in we\ght, besides the larger po<:>kets in the beds.
Scattered through the clay there are extensive accumulatio,ns of black powder, which may be mixtures of various oxides above described. All of them contain some water and often to the extent of several per cent. With all of the manganese ores more or less silica is included, even in the concretionary and stalactitic masses, and in the prepared ore more or less clay adheres to the grains or lumps.
Besides these ores there are in Georgia many admixtures of manganese and iron ores which are of value.

COMPOSITION OF THI!: ORE~.
At the disposal of the survey, analyses from a few localities have been obtained, but they are types of the ores in the Knox series. At the mine of Major J. M. Couper, south of dave Spring, the purer ore yielded the following analysis to Mr. J. Blodget Britton: Metallic manganese _____ __ .. _.. ____ ____ _.: ___. ____ . ___ 53.44 Ferric oxide ___________ -- _______ __ ____ _ ____ _____ 2.83

Baryta __ --- - ----- -- ---- - - - - - - - ---- --- - 8.62

Water ________ __ - - - ---------- -- --- - - - - ------- -- 1.56

Silica ____ __ ____ . . _ -- __ __ _ - - - - - ------- - -- -- - 7.79

Alumina

.. -- - - . _

___ __ ___ _____ ___ - - - 1.52

Lime ____ __ ____ ___ _ - - ---------- --- --- - - -- ____ __ 0.08

Phosphoric acid (Phosphorus, .064.) --- ---- -- - -- - -- - 0.147 Oxygen with manganese, undetermined, etc _______ . ___ __ 24.013

100.00
(13}

194

ECONOMIC RESOURCES.

In_this case the potash was not determined. In other samples

the amount of watir is larger. For commercial purposes the

analyses of car load lots is of more .value than that of picked

samples.

On December 1st, 1889, a car load of 30,200 pounds, from

Major Couper's mine, yielded the following results:

Manganese __ _____ ___ __ -- --- ___ - --- -- - - __ _ __ ____ 46.749

Iron __________ .--- --- - - -- ___ __ _

_ 1.746

Si1ica ______ ____ _______ __ --------- - -- __ ___ __ _13.050

Phosphorus _____ ____ _ - --- ____ _____ ---- _ _ 0.059

In October, 1890, shipments from residuary surface ores yielded:

I.
Manganese ___ _.42.685 Iron __ ___ -- --- 1.729 Silica.. ___ - - _10.000 Phosphorus ______

II. 42.938
5.240 8.009

III. 42.578
1.50 11.95
0.089

IV. 42.307
2.40 10.39
0.072

On Mr. Asbury's property, northeast of Cave Spring, surface ore sent to Carnegie & Co. gave the following result:

Manganese Iron .. _ Silica ___ __ Phosphorus _____ .

- - - ----- - ___45.189 7.840
--- 7. 62 0.053

The ore from the Barnsley estate at Woodlands gave the follow~ ing analysis to the Pittsburg Testing Company:

Manganese_ _____ ____ .... . __ . ___ _.. . ____ __. __ -__ . -43.730

Iron _. __ __-____ . ___ __. ___ __ _.

- - _ _ _ . _ _1. 10

Silica ______ ... _

----- --- ____._:3.5:0

Phosphorus ______ _ __ __ _ __ __ __

- ---- - -- --- - -0.129

Many other analyses of car load shipments to Carnegie & Co. have been seen but the above are representative products of the washed ore.

MANGANESE.

195

In all of the ores moisture is included to the extent of from 1 to 8 per cent. The silica varies from 7 per CQut. up to J 6 per cent., which makes the ore less desirable, as it should not contain over 12 per cent.
The iron ranges from 2 to 14 per cent. or more. The shipper is paid for the iron, but its low price compared with the manganese reduces the value of the ore. In many deposits the amount of iron is so large that the mineral may be considered as a manganiferous uon ore.
The presence of phosphorus has an important bearing on the value of the ore, as its greatest use is in steel manufacture. Good ore should not contain ovet 0.2 per cent. of phosphorus. However, the ores of Georgia manganese are usually as low in this objectionable element as those of Virginia, which yield the largest supply. A large number of shipments of ore from Georgia show only from 0.05 to 0.167 per cent. of phosphorus, and the ores are consequently low in this element.
In the working of this ore it is very important to reduce the quantity of silica or chert by sorting and washings.
MODES OF OCCURRENCE OF MANGANESE ORES.
Manganese ores occur in the Arcbrean rocks of Georgia, as near Mount Airy, in certain semi-metamorphic rocks, whose age has not been settled, eastward of Cartersville, and in the Knox dolomite series of the Lower Paleozoic group. The Cartersville ores have been extensively worked for many years, their product in 1887 being 9,024 tons and in 1888 15,568 tons. Thos~ mines border the zone of the 1present survey, but in this chapter they will not be discussed further than the statement that they are associated with certain metamorphic sandstones and shales, and are often of a more highly crystalline character than those belonging to the Knox zone.
Manganese occurs in mountain folds all the way from Nova Scotia and New Brunswick, along the Appalachian ''ally from Vermont to Alabama, and in a like district of Arkansas. This

196

ECONOMIC RESOURCES.

metal is not confined to one Paleozoic horizon but occurs in Cambrian rocks of Virgini~, the Knox or Calciferous series of Georgia, beneath the Upper Silurian of Arkansas*, whilst on the Bay of Fundy the ore is found in Lower Carboniferous rocks. Throughout the Appalachian regions the manganese deposits occur in formations skirting the northwestern side of the crystalline rocks, which, in Georgia, are seldom more than 25 miles distant.
The manganese deposits of Polk, Floyd and Whitfield, and border of Catoosa, counties have not been correlated with those extending from Tennessee to Virginia, aJild occupy, in part, a different horizon. WhilAt in those States, the ores occur near the contact of quartzites, of various ages, and succeeding shales and limestones, sometimes being in one or another of these beds*, the manganese of the belt from Polk to Whitfield counties occurs in beds of residual clays and cherts, belonging to the Knox dolomite series, and more particularly on the ridges of the western portion of the zone.
The occurrence of manganiferous clays is common in the mountain states. But in this western manganese belt of Georgia, the clays and cherts have been entirely derived from the earthy and impure Knox dolomites, deecribed in the local geology of Bartow county, in the first part of this report. There, the limestones are shown to be in part earthy and in part highly chP.rty. These are eas-ily disintegrated by leac~ing of the calcareous matter, leaving more or less confused sheets of clay in some places, whilst in others there are cherty accumulations, or these only partially depleted of the calcareous matter. The clay deposits have been the most easily eroded, and hence form valleys qont!lining often low ore bearing hills. The more cherty beds afford protection against erosion, and hence are most commonly seen on the ridges, although
*See the excellent Report of Dr. R. A. F. Penrose, on the Manganese ores of Arkansas. Geological Survey of Arkansas, 1887.

MANGANESE.

197

sometimes the top of such ridges are covered with a mantle of red clay, with little or no chert.
The ore was originally bedded in the clayey or cherty dolomitic sand, perhaps as the carbonate, but more likely as a hydrous oxide, in position simqar to its modern occurrence, in the clay. It probably now differs from the original form of deposits by such ~haoges as are ineident to the beds which have been disturbed upon the removal of the calcareous matter. Whilst the depth of decay of the rock is known to exceed 210 feet, in places. The exploration for manganese has not been carried to the solid rock, except where occasional protrusions of semi-undecayecl rock approach the surface, -in which the ore is sometimes seen; yet occasionally masses of rock have escaped decay and are embedded in the decomposed rock or clay, thus sometimes causing the structure to be deceptive.
The manganese is found in the form of grains, nodules, pockets or lenticular sheets, conforming more or less to the bedding. These lenticular beds and pockets are of various sizes and forms, and may be very much disconnected, or occasionally united with stringers.

FIGURE 25.-Decay of Knox dolomites; L, the lower calcareous beds, weathering to siliceous loams; C, cherty dolomite, weathering to sandy soil with cherty gravel and loose blocks on the soil; M, pockets of mnnganese or iron in the decayed remains of limestone; S, surface red soil with fine concretious ore.
The relation of the lenticular beds to the undecayed rock is indicated on the late Bank's property of Major Couper.
On the side of a ridge, on the Couper property, the cherty beds (c) are seen at several horizons, dipping at about 20 southeastward.

198

E CONOMI C RESOURCES.

Between the somewhat disturbed beds, there are the residual clays derived from the limestones (L), and in these, manganese pockets (M) are seen (as shown in figure 25).
On this same hill the upper beds have been most disturbed, and above the manganiferous residual clays the cherty layer is very much broken. Overlying this again is the surface mantle of manganiferous red clay. In this section iron ores oceur in po!>ition above and below the manganiferous beds.
The ore in the individual pockets may amount to hundreds of tons. These pockets sometimes contain massive ores, or else are composed of an aggregation of nodules, the whole following the bedding of the original rock, which generally dips southeastward.
There are also thin seams of ore or layers of nodules penetrating the clay or rock in various directions, and brown ore is often commingled in the beds. The chert and cherty clays are usually gray, or sometimes brown, or pockets of black clay are colored from presence of finely eli vided ore.
The color of the beds varies. It is often deep red or chocolate tinted from the presence of manganese. Again, it may be yellow, brown or black, and beneath the surface often like that of the typical gray cherty land.
The depth to which the ore descends is not known, but as the lenticular beds sometimes dip 20, or more, the pockets of the ore may be eventually reached in solid rock, which, however, will be generally found only below the drainage level, as the rock decay is very deep.
Closely related to the manganese beds, brown ore is often found, even almost in contact with the manganese, as at Tunnel Hill. These iron ore beds, however, are of great extent and more constant than the manganese deposits, but the higher price of the manganese permits of the working of the less concentrated mineral.
The chocolate-colored surface clays result from disintegration of the rocks which may be free from any large cherty particles. Such

MANGANESE.
conditions occur on the summit of many ridges, whilst the low~r porti01;s often show, in places,. more or less partly undecomposed and often cherty rock.
Through the surface residual clays the ore is scattered in small particles, nodules, or even large masses of a ton in weight. It is possible that a portion of these grains and concretionary masses are not simply residual from the decomposed rock, but are of secondary chemical or molecular origin; owing to segregation in the porous residuary earths, and thus concentrated since the decay of the rock, especially in the red surface clays.

200 '

E GONmU C RESOURCES.

CHAPTER XXIX.
LOUAL DISTRIBUTION OF MANGANESE OREI:! IN THE KNOX SERIES.
CONTENTS.
UAVE SPRlNG DIS'l'.RIC'l'. WOODLANDS 0~ BARN8LEY DISTRICT. TUNNEL HILL DISTRICT. WORKINGS O.F MANGANESE DEPOSITS.
There are three principal distl'icts of manganese occurrence in the Kno'x dolomites of northwestern Georgia: These are on ridges extending from south of Cave Spring northward to near the Etowah river; a belt near the border of Bartow and Floyd counties, north of the Etowah river, in the region of Woodlands (Ba~nsley estate) and the Tunnel Hill district, on the border of Whitfield and Catoosa ronnties.
These districts are of broad extent, and include the distribution of the belts occupied by parallel ridges.
CAVE SPRING Dl:OTRICT.
Manganese ores occur along with the iron at many localities, but the most important deposits are on a belt commencing in Polk county and extending eight or ten miles northeastward, with occasional scatte:J:ed deposits to near the Etowah river.
The largest deposits which have been exploited are those of the Georgia Manganese and Mining Company, commencing in Polk county about two miles south of Cave Spring, and extendi~g two and a half miles northeastward. The best deposits are on lots 1140, 1162, 1163 and 1141 (Bartow), 3d district (Polk county); 1009 (Ware) 1233, 1216, 1217, 1160, 1161 (Dougherty) and also on lots 947, 998 (Hancock), 1146 and 1142 (Floyd county).

MANGANESE.

201

The principal works are on a bill 195 feet above the valley of Cedar creek. The summit is covered with a red or chocolate or brown clay, varying from 2 to 15 feet in thickness, and containing manganese gravel. The ore of the surface clay is mostly in small grains and nodules, although masses of a ton in weight have been met with. Through the clay there is also much coarse manganese powder, which is not of value at the present time. It is probable that this clayey surface of the ridge was formerly more extensive, but bas been washed from the sides of the hill.
Beneath the clay covering the deposit is brecciated cherty clay and the disturbed remains of the decayed manganiferous cherty limestone. (See figure 25, page 197.) Through this clay some layers appear to be entirely free from man"ganese. But other seams contain lenticular masses or pockets of manganese ores; and the general position is probably that of the original beds of dolomite, dipping at about 20 southeastward. A shaft has been sunk to a depth 50 feet and has penetrated large masses of ore.
Stringers of manganese extend irregularly through the ore-bearing lands. While much of chert is broken up and cemented into brecciated conglomerate, masses of partially undecomposed cherty rock occur in the clays. As far as the shaft has been sunk there is no appearance of the original solid rock.
Near by, on the sides of the hills, the partially solid strata appear with the beds, dipping, in some cases, as low as 10, nearly eastward. Layers of manganese ore are seen, especially in the clays of the decomposed limestone, above and below some of these beds. Much of the ore is concentrated by the remo~al of calcareous matter, although part of the manganese has also been lost. Some of the manganese concretions in the clay may have been segregated from the mineral dissolved out of the original rock, and thus a portion of the "shot-ore" pellets and concretionary nodules may be arcounted for, especially in the Emface clays. (See figure 25, page 197.)

202

ECONOMIC RESOURCES.

At other openings, the ore is seen in more cherty decayed rocks than that just described. Between the conditions of the surface, red clays and the ore in the cherty residual clays, there is every variety of conditions of occurrences.
The ore beds, just described, have associated with them two extensive deposits of bro,vn ore. This commonly close association of iron and manganese ore has already been refened to.
Northeast of the Georgia Manganese and Mining Company (Major J. M. Couper, President) property, the surface ore is shown on the lands of Mr. Asbury (lot 922), Mr. Simmons, and others. On Mr. Asbury's, the lower part of the hill is cherty, and the manganese accumulations are scattered over the red or chocolate colored clay.
Again, to the northeastward, the manganese occurs on ridges of red laud belonging to Mr. W. I. Taylor (lot 840, 3d district), and on other adjacent hanks.
On a ridge to the eastward of the last deposit are the Rice or Hatchet manganese beds (lot 822, 3d district), near New Prospect church (lot 822). Mt. Harper, of Rome, and others own portions of this ridge. The summit of the ridge is of red clay, but the lower portion is of gray cherty formation, with masses of the rock of the same structme as the other deposits seen in the Cave Spring district. Brown iron ore also occurs on this ridge.
The localities given arc only a few of the known deposito; in the district, hut they locate the belt, and are typical. There are many places, whete explorations have been made, pits sunk, and more or less ore takeJJ. out.
The ores in this belt are not confined to one series of ridges but occur on several parallel hills, and extend on the Polk-Floyd county line, from Major Couper's mine to near the C. R. &C. Railway, as seen on the lands of Mr. Stokes__:__the belt of country having a breadth of several miles.
Longitudinally, the deposits are interrupted, not only on account

MANGANESE.

203

of the topographic features, but on account of the nature of the deposits being large in some portions of the beds, and almost inexplicably nisappearing in others.
The geological conditions for the occurrence of the manganese ores continue from northern Polk county to the Etowah river, although narrowing somewhat in breadth in passing northward; laterally, the belt extends ftom Van's valley, to near Spring creek.
Manganese and manganiferous iron ores also occur in the narrow Knox basin west of Cave Spring, already referred to in connection with iron ores. The manganese is on Mr. Simmons' and other properties. These deposits are about two miles west of "Hematite Siding" on the East Tennessee, Virginia and Georgia Railway. The basin is narrow and only a few miles in length, and totally disconnected from the Cave Spring district by Cambrian shales.
THE WOODLANDS OR BARNSLEY DISTRICT.
On the low ridges adjacent to the valley of Tom's creek, manganese is found in deep red or chocolate colored loam, like that on the top of Couper's hills, near Cave Spring. In places there is scatteted chet't upon the surface of the ground. The occurrence is similar to that near Cave Spring. One pit, 20 feet deep, was opened, and fifty tons taken out of it. In part, the deposit resembles a breccia, with manganese oxides for the cement. In this locality, there are a large number of deposits exposed on the surface, but not opened (see land lots 95, 63 and 84 and lot 36 of Mr. Morrow, and lot 97 of Mr. Conway). Brown iron ore occurs in proximity to all of these deposits, and so does beauxite.
The ores of the belt continue in ridgE's to near Nannie, where large surface accumulations of manganiferous nodules were seen on the land of Mr. Price.
TUNNEL HILL DISTRICT.
A narrow belt, mostly a chain of ridges, extends from a point west of Tunnel Hill, east of northward, into Tennessee. This chain of ridges is of variable elevations, sometimes rising over 100

204

ECONOMIC REf:>OURCES.

feet. n is prim:uil a chujn of gray h ty lant) , al bough man y
p int show but littl ' ch .L"t upon h urfac , where t hat is of r ed so il. 'Ibe or in the anr facle pits is mostly iu t h red re inual clay, which baJ:J a variable depth.
pon this belt, at about t nree mil from T tmnel J-lill, h at a Minincr ompuoy have made some exteru ive op nin t\ud diffi.r nt shafts-on said to b 21 fi et iu t h r idnal decayed cLel"ty c1ay1l. Mangane. e, often lo: ] re ern:blin.,. that l; 'of ar-
t ... ville (m()re or l :s crystallin e) is l'i en ou th stufa .e about
the e mines, which wer I. , ua t th ti.me of my vi it. At seve1a.l
pit up n th sndace brown iron m e 1 al so xpo. ed . 'l'b two miuernl in one place, come i nt lo e Flation hip. Part of t be iron is a fhr -mtmgau ' or" Th d p ore in t h e g1ay ar th wn ttot een, wing to the shaft being lol'ied.
Manganese ore was seen to limited extent upon the ridges of Knox dolomite southwest of Tunnel Hill and at other points, but the quantities were not large.

THE WORKINGS OF MANGANESE DEPOSITS.
Hitherto the manganese bearing surface clays have heen screened, as in case of brown ores, and several pockets have yielded a few hundred tons.
Pits ha ve not often b - n nnk mot thun b nty r tbil'ty fc t.
The 1 L eri u attempt at prop rly worlcing tho l 'O ' in thi belt wa 'r'l Jnruen ] b ' M aj . J. (. ouper, ~\t tl1 mines uear ave Spting. H ere an improved p.laut wu cou t.Ju ted w:itb two ' rn i. b r .II. , d tlbl log wa her screen , fiv e- g i.ggers, tc. The water for wnsbiu" is brought fr m edat ree k, a nl.iJ e a..;vay. It .is only by meau f Lbe improved m Lh d10 f wn. hiuu t ha the sepal'utiug f t he sil iceo m1 matt l' fl'Om the ore can b Hati factorily aoa rnplished.
At Tunnel Hill a still more extensive plant has been constructed, but it has not been in operation up to the present date.

MANGANESE AND IRON.

205

CHAPTER XXX.
ORIGIN OF MANGANESE AND IRON DEPOSITS.
The position and general relationship of the various belts of manganese ore have been described. But if their origin were better understood, this greater knowledge of the necessary condition~ of depoeition would be of service in determining the variations in the modes of occurrenoe and distribution of the ores.
The rocks of the Paleozoic belt of northwest Georgia were formed from the degradations of those of the crystalline or metamorphic zone to the eastward. From the enormous decay of those rocks, the manganese, as well as the iron, was obtained. Many of the crystalline rocks contain much iron; and where iron occurs, smaller proportions of manganese usually are found. Along streams and springs one often sees deposits of yellow or red oxide of iron, and sometimes stains of black (from manganese). Th'lse encrusting deposits have been derived by chemical solution from old(j.r minerals and have subsequently been redeposited. Such transportation, ac0umulation and deposition can be seen going on to-day.
Among the commonest crystalline rocks in Georgia are hornblendic, or syenite gneiss, and granite, garnet rocks, etc. Manganese is associated with the iron of the hornblende, garnet, pyroxene or other rocks. Thus in the decay of these silicates, iron, manganese and aluminous compounds are liberated. Some other materials, suclt as rhodonite or silicate of manganese, hold the metal in a more concentrated state in pockets in crystalline rock. But the great supply comes from the concentration of the metals from the common rocks, containing only small a proportion of iron and manganese.

206

ECONOMIC RESO~RCES.

The decay of the crystalline rocks has been in progrees for au enormous length of time, but a great portion of the disintegrated material is washed off into the streams and carried into the sea to build up new lands.. The crystalline rocks at Atlanta are decayed so far that they may be considered completely rotten to a depth of 95 feet. However, incipient decay may reach as much as 300 feet In the disintegration much of the iron, manganeee, and some alumina have been leached out of these rocks and deposited elsewhere.
The agents of rock decay are carbonic and various vegetable acids acting mainly on and near the surface of the rock; also sulphuric acid, arising from the decay of pyrites in the rock. These acids, in the presence of reducing agents, haYe the power of dissolving out the iron oxide and manganese, along with the magnesia, potash, soda, etc. bf the rock. The removal of these compounds leaves the rocks porous and favors the erosion by rains and rills
The carbonates of iron and of manganese are carried off by the streams and are sooner or later deposited as the oxide or sometimes as the carbonate; the carbonate of manganese, appearing somewhat more stable than that of iron, is apt to be carried farther than the iron, or at least more or less separated from it; for the carbonic acid upon exposure escapes and the mineral becomes oxidized, as seen in the coatings of the red or the black films of these metals upon pebbles, rocks, etc.
The iron may be taken up and afterwards deposited as the sulphide, but this does not appear to be the case with the manganese.
Such being the primitive somce of the brown iron anu the manganese ores, their deposition would be expected along the streams nnd in basins lying not distant from the zone of rock, which gave origin to the metallic accumulations. Thus the manganese belt is situated upon the northwestern flank of the crystalline or metamorphic formations.



MANGANESE AND IRON.

207

The Paleozoic rocks which contain the manganese and iron were derived from the same sources as the metah; (the calcareous matter being indirectly secreted from sea water through the agency of marine organisms); and amongst these accumulations the ores as well as clays and beauxite were deposited. The~;e ores are most abundantly founi in the limestones, and to a less extent in the shales, but east of the belt of exploration they occur in the sandstones and slates.
As has already been seen the ores follow tht trend of the ridges, being in zones whose general course is a little east of north. Also it has been shown that the deposits are not continuous throughout th& zones. It has been further pointed out that the richer deposits are on chains of hummocks trending westward.
Any one familiar with the various coast lim~;,; is aware of the common occurrence of low islands, numerous channels and lago~ms, such as are found along our own shores. The manganese, being converted into the solu b'le carbonate by superficial waters, at its original highland source, was borne by the ~:>treams which were eventually retarded upon entering the dismembered water basins along the coast. Adjacent to the streams, and in the quiet waters of the lagoons or the estuaries, the conditions are favorable for the conversion of the soluable carbonates of manganese into oxides. Under these conditions, the metals borne down by many streams, in both solution and to a small extent in a finely divided mechanical condition, would haYe been deposited in. separated basins, all of whic.h we.re, however, in a general trend, parallel with the direction of the coast line. Thus the interrupted character of the ore beds can be accounted for.
The metals are generally disseminated to a small extent amongst all the rocks, but they are concentrated only in limited areas.
The same streams brought down more or leso clays and sands as mechanical se.dirnent. These were deposited along with the metals and greatly in excess of them. (See Origin of Beanxite.)

208

ECONOMIC RESOURCES.

As the ores under consideration occur in limestone deposits, it is probable that the lagoons may have been similar to those amongst aoral reefs; even the intercalated siliceous beds are poorer in the metals than the more calcareous layers. The ores of the clay and sandstone regions may have originated in local basins similar to those on our own coast, interrupted by sand bars ~nd islands.
Other sources may have given rise to a small quantity of the ores, but those of Georgia have originated entirely from the decay of crystalline rocks brought from the older Archrean lands into the basins in which the Knox dolomite was being accumulated.
In some cases the ores were originally segregated into large pockets. But the secondary decay of the Knox rocks in removing calcareous matter, bas further concentrated the metals into a smaller volume of rock. Especially upon the surface, this is noticeable, for.here the clays and sands have been to some extent washed away, which has scarcely been the case within the mass of the rock.
Furthermore, the ores Hpon the surface in the residual clays may not b.e entirely in place, hut have been partly concentrated by washes from other portioll'l3 of the higher hills, now reduced far below the level of the protecting gravel ore, on account of the erosion of the land surfaces.
In this connection it is again suggested that the concretionary and stalactitic nodules may have been originated in part by a secondary solution of the finer particles of ore ~nd been redeposited in more concentrated forms in the surface clays; So, also, in the crevices of the lower clays, and in the spaces amongst the brecciated rock, the ore sooms and cementing ore were concentrated by the filtering waters, from the man~nese poorly scattered through the rock mass.
In all cases the ore is largely associated with siliceous materials, part of which came from the lands, but part from those secretions along with limestones which produced the chert, and this

MANGANESE.

209

excess of silica is that which must be rejected in the use of man-

ganPse compounds.



If the workingsJ:of the manganese beds b~ carried down below

the drainage levels and decay&of th(rock, the larger pockets of ore

will probably be similar to those seen in the clay, and the partially

decayed cherty rock, but in a more compact form. However, the

ore in smaller pockets and nodules will likely be found less c~ncen

trated and more sparsely disseminated as the great volume of

calcareous matter of the rock has not been removed by solution.

(14)

210

ECONOMIC RF;SOURCES.

CHAPTER XXXI.
ALUMINIUM ORES.
CONTENTS.
NoTE oN ALrM AND ALuMINIUM. SouRCES oF ALUMINIU~r-Betmxit e : Cryolite, Kaolin, Clay HALLOYSITE AND GIBBSITE.
NOTE ON ALUM AND ALl'MINIUM.
Aluminium compounds ate much sought for in the manufacture of alum, etc., which is used in great q nantities as a mordant for setting the colors of dyes, ann still more largely for sizing in the manufacture of paper, these two requirements consuming an enormous tonnage of the different ores.
To these demands others have been added in the production of aluminium. The uses of this metal are now growing very rapidly, .owing to the reduction of its price. Its earlier uses were restricted on account of its high price. Until 1884 all of the metal used was imported. That yeat the importation amounted to 590 pounds, valued at $8,416. In 1~83 Colonel Frislnnuth, of Philadelphia, ptoduced 63 pounds, and in 1884, 115 pounds. Since then the production has very rapidly increased, so that in 1889 it amounted to 47,468 pounds, valued at $97,335,* and in 1892 the ptoduct was increased to about 350,000 pounds with a further diminution in price to 50 cents a pound, although it has been again advanced in price as the supply is not equal to the demand. It is variously estimated that the cost of production can be reduced to from 18
" Bulletin of Eleventh Census, No. 79.

ALUliHNIUM ORES.

211

to 20 cents per pound (Hunt.) The demand for the metal is rapidly increasing on account of its lightness (one-third that of copper) durability, etc.

SOURCES Oll' ALUMINil:l\L
The primitive sources of aluminium are the crystalline rocks which contain this element. Indeed, next to quartz, it is the largest component of crystalline rocks and shales. Amongst the older formations it is locked up in the fornt of the feldspars and micas, in granite, gneisses and schists. In o~her rocks it occurs in various shales, clays, kaolin, etc. Also several minerals are largely composed of it. Thus corundum (with its finer varieties, sapphire and ruby) is pure alumina; cyanite is a silicate; so are garnet and topaz, but these contain various other elements. The sulphate of aluminium occurs to a limited extent in a natural state.
The most important aluminous minerals are cryolite, kaolin (with allies including clay) and beauxite.
01'yolite is the double fluoride of aluminium and sodium. It i8 imported entirely from Greenland to the extent of nine or ten thousand tons a year, at a cost of from $9 to $10 a ton. It contains thirteen per cent. of aluminium or about twenty-four per cent. of alumina, but its value is enhanced by its contained soda.
Kaolin and Cla,ys.--Kaolin occurs in clay-like masses, in texture fi'om compact to mealy. Hardness 1-2.5, specific gravity 2.4-2.63. The luster is earthy to sometimes pearly. It is usually unctuous and plaRtic. Pure kaolin is white, soft and clay-like, and made up o microscopic pearly scales. The composition is typically: silica 46.3, alumina 39.8, water 13.9 per cent. It may contain iron, lime, magnesia or potash in small proportions as impurities, which affect its fusibility as the purer mineral is infusible. Kaolin is a decomposition product of the feldspars,.and is liable to contain free quartz, or indeed, some undecomposed feldspar.

212

ECONOMIC RESOURCES.

Clays are primarily of the same origin as kaolin, but differ in that they contain more or less fine quartz, and undecomposed feldspar, etc. The composition is extremely variable, from almost pure typical kaolin to even a predominance of free quartz.
The kaolin and clays are not considered here in connection with their importance in brick making, pottery, etc., but as association::; of beauxite and iron ores. In the brown iron ore beds, clay ".horses" of great size, and many other beds of white clay are of common occurrence. 'These are sometimes tinted reddish or purple. They also occur of yarious colors, often tinting streaks through the clay. As a type of their composition, the analysis from a clay "horse" in the brown ore deposit at Grady is given in the chapter on clays.
The economic valne of these deposits will be considered as a separate subject. In their associations with beauxite care must be taken in the separation of clays as they reduce the value of the mineral shipped.

HAJ.LOYSITE AND GIBBSITE.

Halloysite is clay-like, massive or earthy. Hardness 1-2, gravity

2.4. The massive varieties may be somewhat pearly with con-

choidal fracture, color white or tinted. It absorbs as much as 20

per cent. of its weight of water. It is infusible, but it is decom-

posed by acids. The typical mineral contains alumina 37.7, sili1:a

43.3, and water 19.0 per cent.

The mineral obtained from the Fort Payne chert, in Dade county,

and analyzed by Mr. H. W. Shephard, of Philadelphia, showed a

colloid form (favorable for porcelain manufacture) and gave:

Alumina __ _. _ _ _ _ _ _ ___ . _. ___ . __ . . . _ 30.76

Ferric oxide.... ------- -- __ _ ________ _ .. . - - - -- 0.36

Silica __ _ ---- -- -- - \Vater __ - - ______ _.

_ --------. ___ __ ___ _

45.15 23.5.5

99.82

ALUMINIUII[ ORES.

213

This mineral occurs in the Fort Payne chert (Sub-Carboniferous). The cherty li1i1estone when weathered leaves kaolin-like clays intermingled with the residual chert. In places these white clays occur in large pockets or irregular beds. Sqme of the deposits form earthy or again porcelain-like, halloysite. Such deposits occur on the property of Mr. Blevin, south of Rising Fawn. Large pockets also occur on property of Mr. Alexander, about .four milea from Subligna, on the eastern side of Taylor's ridge. " 7heu more exposure8 are made, there is no reason why many beds may not be found in the deposits of this formation, which is quite widely distributed.
In the manufacture of aluminium or its compounds, this mineral is inferior to beauxite only in containing a larget quantity of silica, and a smaller proportion of alumina than the former mineral.
Gibbsite, another mineral composed of hydrous alumina in stalactitic, mammillary and incrusting forms, has been found on the Barnsley estate in connection with beauxite. It has a smooth surface, with internally a faint fibrous structure. H=2.5--3.5, gr. 2.3. In color white, grayish, greenish, a reddish white. It has a clayey odor when breathed upon. In composition it is alumina 65.6, water 34.4 per cent.

214

ECONOMIC REHOURCE8.

CHAPTER XXXII.
BEAUXITE.
CONTENTS.
PROPERTIES. ANALYSES. DISTRIBUTION AND COMPOSITION OF GEORGIA ORES. USES OF BEAUXITE. MoDES oF OccuRRENCE. ORIGIN OF BEAUXITE. BEAUXITE IN GEORGIA.
PROPERTIES.
It is a concretionary pisolitic granular mineral, also earthy and clay-like. The luster of the more compact varieties is often waxy. Hardness from one to about three; specific gravity 2.55. In color it varies from white to gray and deep red, according to amount of iron present. If the iron be regarded as an admixture, the mineral is a hydrate of alumina, with a composition of: alumina, 74.1; water, 25.9 per cent. In this case the composition is near another mineral-diaspore-which is not found in large quantities. But a portion of the alumina is replaced by variable quantities of ferric oxide, and silica is present, probably from admixture with kaolin. Titanic acid is always present in the Georgia mineral, and traces of lime, magnesia and rarer elements also occur. Accordingly, the mineral is of variable composition. Its appearances are deceptive, as often the most perfectly concretionary forms are of lower grade than those less promising. The clay-like varieties have been called Wocheinite.

ALU)UNJUM ORES.

215

Sometimes the pisolitic conctetions are deeply co lored with iron, whilst the matlix is of lighter color. Near the urface the mineral

Fwun~> :26.-Section of a con cretionary pebble of beaux ite, showi ng pisolitic structure. The pellets vary in size from small g raim to an inch in diam eter -but th e smaller sizes are commonest.
is often vesicular, owing to the removal of t he alumina ftom the interior of the cavities, in which siliceo us O\' ferl'llginou s dust alone is often left. Thi removal of aluminous matter redu ce the value of the mineral. The quantity of iron often increase with th e depth of the deposits below the . ul'face; still the iron is no objection, as a vahmble by-product is obtained in the manufacture of alumina. A numbet of analyses of beauxite were made by Prof. H. C. White, Pre ident of the State College. These were chosen as type of different varieties from variou localities in Floyd and Bartow conntie. , and were not taken frorn the deposits, becaus~ t hey were known to be of good quality.
ANALYSE3 OF GEORGIA BEA XITE.
Sarnple 1.
At Flowery Branch (lot 21, 23d district) nea r H ermitage, Floyd >COUnty .

216

ECONOMIC RESOURCES.

Variety: 'Vhite porcelanous mass, with subordinate pisolitic grains; associated with white clay beds upon the side of a ridge: .

Alumina ___ _____ __________ __ ___ -- ----- -- --- -~ ----46.72

Ferricoxide ____ ___ - --- ------- - ----- -- . 2.1-!

Silica _

-- - ----- -- . -----

Water_______ __

Titanic acid ___ ___ _____ _

- - - -- - 29.01 . 20.15
-- - -- - - 0.87

Sam:ple 'lJ.

From Mr. Doyle's (lot 906, 3d district) farm about seven miles northeast of Cave Spring, Floyd county.
Variety: Large concretionary pellets of whitish color stained with iron oxide. Interior of pellets partially dissolved away, leaYing a semi-vesicular mass somewhat pooret' in alumina than wonld be expected. It occurs in the valley:

Alumina ______ _____ . ____ _ ----

_______ - ----- .52.13

Ferric oxide . ___ .. . ______ __. ___ . ___ _. _ _ ____. _ _ 1.12

Silica ___ __ - - - ---- - -------------------- __ --- ___ 19.56

''Tater. . -------- - --- _______ .. ------ ___ ___ 24..,.:L

Titanic acid . . -- -----

-- - --- ----- 2.0R

Sample 3.

From land of Mr. Culberson, one mile from Cave Spring. Variety: Small pisolitic concretions in mass, grayish white, with some iron stains. It occurs on top of a ridge:

Alumina _____ - - -- ____ ___ ___ ----_------_ 39.75

Ferricoxide ___ ______ ___ __ __ __

_ ___ ---- - 1.62

Silica ___ ______ _____ _ ____ ___ _ -- - - ------------ _41.47

'Vater ___ __ . - . ___ _____ __ ____ -- --- -- _ ___ _16.14

Sarnple 4.
On a farm of Mr John Henry (lot 910, 3d district) near New Prospect church, six miles northeast of Cave Spring.

ALUMINIUM ORES.

217

Variety: Light reddish porous mass, as the interior of the grait1s is largely dissohed away; somewhat earthy. At a depth the min-

eral is not likely to be so porous as on top, and consequently richer in alumina. It occnrs on side of a ridge:

Alumina_____ __

------- __________ __ ___ _o6.1

Ferric oxide ______ __ --- ___ __________ __ ___ _10.64

Silica _ __ ___ ----- - ------------------------ -- __ 2.56

Water _____________ -- ---- --- _ ~ -------

_30.10

Sample 5.

Near the last named locality.

Variety: '"'hitish mass, with occasional pisolites. Taken from

side of a narrow gully:

Alumina _______________________ _

- 58.61

Ferric oxide_ _ _________ .

2.63

Silica ______ _ -- ---------- ------=- ---- ----- - 8.29

Water_________ _

----------- -- -- - -- 27.42

Titanic acid

- ----------- 3.15

Smnple 6.

On land of Montague & Company (late Mr. Connaway, lot 97, district 16), Bartow county, north of Kingston.
Variety: Earthy and white with reddish concretions. It is
located on side of a ridge:

Alumina ____ ---------~--- ---- --- ---------- 43.18 Ferric oxide __________________ _ __ ____ __ _ _______ 8.74

Silica _ ___ -------- ___ . --- - - _

_ ___ 28.11

Water ____ _________ _______

______ _______ 19.22

Sc;.mple 7.
On lot 61, 23d district. Variety: Earthy looking mass of large concretions. Adjacent deposit is of higher grade. The sample was chosen to see whether

218

ECONOMIC RESOURCES.

much beauxite were lost in the rejection of the poorer and more clay-like earths. It is a clay mixed with much beauxite:

Alumina _____________ ---------- - - - _----- . --.36.86

Ferric oxide -

1.28

Silica

. ----- -- - - ---- ------ _______ 40.02

Water __ --- -- - -- -

------ --- .20.64

Sample 8.

On land of Mr. A. W. Bobo (lot 534, 3d district), about three miles north of New Prospect church, Floyd county.

Variety: Small concretionary boulder, with small pisolitic grains. Stained with iron oxide along fracture lines. It occurs on side of a ridge:

Alumina ___ _

- ' ( . 2

Ferricoxide __ ------- ------- ---- -- --------- 2.16 Silica __ ___ _ --- ----- - - _____ _ ____ -------- - _ 6.62

Water . ... . __

. ___ -----

__ ___ __ 31.1

Sample 9.

On land of' Mr. Shaw, two miles southwest of Adairsville, Bartow county.
Variety: Mixed white and reddish vesicular concretions:

Alumina_ -------- ... Ferric oxide_ . ___ __ _. Silica . _ . _ _. __ - _ "rater ___ __-- __

51.22
- . --. - -. -- - - 4.83 --- -.13.33 ___ 29.82

Sample 10.

On lot 2:3, 16th district, Bartow county. Variety: Hard red porcelanous mass of concretions. Occurs on surface of a ridge:

Alumina_ --------- - --

---- - .53.31

Ferric oxide ____ __ ---- ___ --- __ _ - -- - - ----- -- __12.92

ALUMINIUM ORES.

219

Silica ___ __ ---- - - _

------ ---- - ---- - -- _ 1.16

Water ____ . ____ _ ------ - ---- ----- - ---- - -- - . _29.60

Titanic acid __ ___ __ __

- - - 3.22

Sample 11.

On Mr. Seay's land, lot 108, 16th district, east of Linwood. Variety: White, small grained pisolitic in mass :

Alumina ___ . _________ __ __ __________ ______ ______ ___ 45.21 Ferric oxide_. __ .. _____ ______ .. _. _____ ________ ________ 0.52 Silica ___ ___ _ ___ -- - - . __ ---- -- ___ ----- 35.88 Water __ _ .. _____ . ___ ______ ___ _ _____ ______ ._ ______ 17.13

Sample 1f8.

On lot 115, 16th dh;trict, belonging to the Barnsley estate of Woodland.
Variety: White, small grained pisolitic in mass. Situated on a flat-topped ridge:

Alumina ______________ _______ .. __ - _____ ____ _______ .61.25

Ferric oxide ___ - - ----- - --- - - - - - - -- - --- - ---- -- 1.82

Silica ___ __ -- - - --- - - -- ------- . - -- - - - --- --_ 1.98

Water . . - ----- - - - _

:31.43

Titanic acid ___ _

- - - - - - -- 2.38

Samples 13, 14, 15. Other analyses of beauxite from the Julia mines (Barnsley estate) yielded the following results to the Pittsburg Testing Laboratory, and kindly furnished by Mr. B. F. Armington:

Alumina _____________ ____ . ... . 67.53
Ferric oxide _ __... - - -- - - - .... trace Titanic acid . -- - - -- - ... ___ 2.92 Silica ___ -- --- - -- - --- - ____ _ 1.34 Water ____ _ _----- - __ _______ _ . 28.00

60.61 0.21 4.18 2.47
32.00

60.63 trace 4.76 3.20 31.00

99.79

99.47

99.59

220

ECONOMIC RE':iOU RCES.

Sample 16.

From the Knowles property:

Alumina ____ __ _ ______ _ - - ----- -- - ----- ---- - - - -61.88 Ferricoxide ___ __ _ __, ____________ ----------- - __ 0.21

Silica ---- --- ---- - - - - ---- --- ----------- ___ __ ___ _ 2.13

Titanic acid _ - - - - _ -- ____ . _

---- __ 4.04

" Tater_ __. __ ____ _____ - _. _.. _ _ ______ -. __ - ~ ___ _ .3 1.50

99.7fi
Titanic is always present, and where not determined separately, it is included with the alumina.
From these analyses, the yariations in composition are seen to be vety great. Some of the samples were from pits, others from the surface.
The vesicular varieties are mostly superficial, and in some cases contain a smaller amount of alumina. The iron seem~; to increase upon descending beneath exposed surfaces, and consequently the redder varieties are more abundant at a depth. Still the amount of ferric oxide is often small, considering the depth of color of the mineral. In some cases, the silica, as if free, renders the mineral gritty, but much of it is combined, so that the siliceous mineral h1ay be regarded as containing a kaolin-like constituent. Indeed. the beauxite is commonly associated with a clay, often of white color. (See clays.)
The ore varies greatly in its affinity for the contained water. In some cases this is easily. driven off by roasting, but other samples require to be heated to redness before losing all of its water. In the above analyses, where 28 to 32 per cent. of water occurs, a portion of the moisture is evidently hygroscopic.
DISTRIBUriON AND CO~fPOSITION OF FOREIGN ORES.
Beauxite iR so named from its oecurrence near the town of Beaux in France, where it occur.~ to a depth of 30 or 35 feet and said to

ALUMINIU.llf ORES.

221

extend for 90 miles. It also occurs in Austria, Germany, Ireland and Scotland.
In America, it was first worked by ::VIr. J. vV. Hawkins, near
Hetmitage, in Floyd county, Georgia. The same belt extends into Alabama. It was also found by Dt. Brauner, State Geologist in Arkansas.
The analyses of foreign ores upon the next page is taken from a treatise entitled, "Aluminium," by Mr. Joseph M. Richards:*

THE USES OF BEAUXITE.
Owing to the large percentage of alumina, and its solubility in acids, the demand for the mineral is rapidly increasing. Of minetals available in commercial quantities, none is so desirable for the manufacture of the compounds of aluminium, especially alumina (the direct source of the metal), the sulphate and compound alums.
The mineral, when powdered, is decomposed by "chamber acid," (dilute sulphuric acid), and the silica is left behind and separated. By this process the iron is also dissolved, and, being objectionable, it must be separated, or reduced to an ineffective condition; consequently, the mineral is not accepted for use by this process when it contains more than from 2 to 3.50 per cent. of iron. However, a large proportion of silica is admissible, up to 14 or 20 per cent., or even more, but if too much is present the quantity of the product is greatly reduced. Owing to competition with the foreign mineral, grades below 55 per cent. of alumina are not genemlly acceptable.
As has been seen, titanic acid is generally present in onr beanxites. This is not an objectionable component, for it can be retained along with the alumina, as so much of its sulphate as is formed acts like that of the other metal in setting the size oe the color in paper mannfaetnre or in dyeing.
;'Publbhed by Henry C. Baird & Company, Philadelphia.

ANALYSES OF EUROPEAN ORES.
i ll 1 1 1 21 1 3 1 4 1 5 1 6 1 7 8 9 1 10 1 12 1 13 1 14 115l l6 1 17
Alnmina ...... C\0 ofril .n-ts 12 43 44 61.8\J 45.76 55.6176 .3 50.f;ij -l!l 02 7:1 .0 t)3 .Hi 72 . 8744.454 1 ll4. o 2!-l .SO Ferric Oxide .. :Ui .U 12 (l 2 36 ::' . 11 1.96 18.9(3 7.17 6 .2 14. 36 12. !!(} 4.:Ui 23.55 13.4930.310 .4 2 .0 3.67 Silica ......... 3 - 0~ 1. 0 7. 95 15 . 05 6.01 6.41 1-!.41 1. 0 5 . 14 10. 2i 2.1 5 4.15 4.2515.012 . 0 7 .fl 44.76 Potash ad'fl. soda .... . .. . . .. .. . . . .. .. . 0.38 .. .... .. .. 0 . 211 0.31 .... . 0 . 79 0.78...... . ... . .. .. Water ........ 12 . 0 12 .0 40 . 33 35 70 27.82 27 .\ll 32.3316 ..1 28.38 25 .91 18 .00 8.34 8 .50 9 . 72:! .924 7 13 86
11, 1 and 2, Beauxite from Beaux; 3, from Irish Hill; 4, from County Antrim; 5, Glenravel; 6 and 7, Hadamar (Hesse);
8, Klein-Steinheim; 9 and 10, Landorff; Commercial quantities from Dublin, imported and .made into alum. Wocheinite varieties: 12, dark; 13, light; 14, Red Brown Beauxite; 15, yellow; 16, white; 17, white, Wocheinite from Austria.

ALUMINIUM ORE~.

22 3

By another process the mineral is fused with soda. In this case, the quantity of silica is restricted to from two to four per cent., a~ more would make its use too costly. It is by this process that the alumina for reduction to the metal is made. Iron in the beauxite is not an objection, for a valuable by-product is obtained.
Ah\minium is now rapidly growing in use in the arts. The abundance of its compounds is coextensive with the clays. In commercial quantities, its oxide, or pure alumina, prepared from beauxite, or hydrated oxide, is the chief source from which the metal is extracted in the largest quantities. The aluminium has such strong affinity for oxygen, that the separation is difficult. Iu the more recent and cheaper processes, the metal is reduced by powerful electrical currents, from alumina dissolved in molten cryolite (which is not decomposed) in an electrical furnace. The affinity of oxygen for the metal is better appreciated by stating that the Pittsburg Reduction Company finds that a horse-power of electrical current, working from 18 to 22 homs, liberates only one pound of metal.
The Yalue of beauxite is regulated by the price of the imported mineral, which can be delivered in Philadelphia or New York at about $6.50 per ton. But the Georgia beauxite commands a higher price, on account of its easier solubility compared with French ores. It has been sought for shipment 'to Germany. As much as $8.50 to $13.00 per ton have been paid for Georgia beauxite in Pittsburg and Syracuse. At interior markets, the transportation from the seaboard must be added, so that the Georgia beauxite can be shipped with better advantage to Cleveland, Lockport, SyracuHe and Pittsburg, than to tboHe coastal cities.
Another application, when deHiccated, is its value as a refractory material in open hearths, especially in the basic processes of steel manufacture.
The quantities of Georgia beauxite are extensive, and with the increasing demand, a large supply can be obtained.

224

ECONO.MIC REHOURCES.

~lODES OF OCCURRENCE 0~' BEAUXI1'E.
Beauxite occurs amongst the residual deposits of the decomposition of the Knox dolomite series, and extends from Polk county to Gordon. It is also found in continuation of this belt in Alabama. So far, it is not known outside of this formatio;J, although Halloysite, a mineral of similar composition, occurs higher, in Sub-Carboniferous series. At .Beaux, the mineral occurs in grains in compact limestone. In Arkansas, the beunxite lies between soft Tertiary beds (Branner), adjacent to igneous rocks.
In Georgia, beauxite deposits are associated with the higher members of the Knox dolomite series, and the belt is closely coincident with the manganese zone, but not with the more cherty members of the series. In elevation, the beauxite bearing ridges are usually 800 to 1,100 feet above the sea. The beauxite occurs upon the sides of the gently sloping ridges, especially in coyes amongst them, and not usually upon the detached and subordinate valley ridges, as in the case of the best iron ore deposits. Brown iron ore deposits occur in the vicinity of all accumulations of the aluminous mineral seen, and manganese is found upon higher portions of the same or adjacent ridges. Beauxite appears in nodule.~, and in more or less earthy forms, in pockets, and in ill defined IJeds in the residual clays of the Knox dolomites. Its mode of occurrence is more or l(>SS similar to that of brown ore, (>Xcept that the softer mineral has not withstood surface degradation as well as the iron or manganese ores. Sometimes the nodules are small, but again large boulders are seen. Thel'e deposits are known to reach a clepth of 50 feet or more, but the full extent has nowhere been proved.
The surface of the ground is frequently yellowish, and with bnt little flinty covering. Upon it, boulders, nodules, or sometimes pebbles of the concretionary mineral, are strewn. The mineral is oftee only sparsely scattered through the snrface clays, in which

ALU~HNIU~f ORES.

225

occasional boulders alone may occur, as if dumped into the mud of a sea bottom ; such, of course, is not the case, but this condition probably arises from the creep of earth down the hillside during long ages; thus, the' beauxite beds are sometimes covered by from two to eight feet of clayey deposits. Consequently, the source of the beauxite is sometimes higher than the localities, where it appears upon the surface, although generally it is to be found near by.
THE ORIGIN OJ<' BEAUXlTE.
This is an open question. Its situation along with the iron and manganese ores in dolomites suggests a common genesis. The formation skirts the crystalline rocks of central Georgia, whence the materials were originally obtained. Prof. Brauner says that the Arkansas beauxite, although in Tertiary rocks, is located near eruptive syenites, or hornblende granites. Such rocks in Georgia have given rise, in part, to the iron and manganese minerals. The feldspar, in othets, contains the aluminium, and there remains only the necessary Rolvent to transport and deposit it as the mineral beauxite.
In the weathering of the rock~ carbonic and vegetable acids remove the iron, manganese, lime, etc., from the hornblende, and potash and soda from the feldspar. So also carbonic acid in water can dissolve small quantities of alumina; thus the same waters can remove the iron, manganese and alumina.* The alkalies derived from the decay of feldspars can also dissolve the alumina. Thus.
transported, the alumina may be precipitated i in the lagoons in
*When alumina is precipitated by fixed alkaline carbom\tes, a small portion of alumina remains in solution at first, but this is deposited by degrees after the solution has stood a few days in the open air, at a temperature sufficient to expel the carbonic acid.-( BeTgman.)
t The above explanation of the origin of the beauxite deposits is supported by
Coquand in writing upon the French mineral, but differs in not being due togeyser action.
(lo)

226

ECOKOMIC RESOURCES.

which the ferruginous and manganiferous clayey limestones were being formed. The white clays associated with the beauxite and iron ore deposits are usually of fine texture, indicative of deposition in quiet waters. The frequent replacement of part of the alumina by ferric oxide further shows the presence of both metals in the original solution, but in variable quantities at different times and places.
Upon the subsequent decomposition of the Knox limestone, the calcareous matter being removed, the ores were concentrated, leaving accumulations of beauxite more prominent than in the original beds.
The position of the beauxite appears to be more or less in pockets and lenticular masses in certain strata, and if workings are ever carried beneath the decayed rocks, the mineral will likely be found in pockets in compact limestone. Indeed: some of the apparent clays may be found to be the soluble aluminous mineral, which is so far as known in Georgia, generally more or less oolitic and concretionary, as are the iron and manganese deposits. The beauxite beds or pockets are less interrupted, and are much more extensive than the latter named mineral.

BEAF XITE IN GEORGIA.
'
The general distribution of the belt of ore is now known, and a large number of deposits have been visited. Often they have been found on different parts of the same ridges with apparently no reason for their intervening absence.
The beauxite also occurs on many properties adjacent to those given but not mentioned, as land boundaries were not known.
About a mile northeast of Cave Spring, a light colored yariety occurs on the summit of a ridge belonging to Mr. Culbertson. The bed appears to be quite extensive; and some of the ore is reported as giving a higher analysis than that of the specimen reportell on a previous page.

ALUMINIUM ORES.

227

At other points, a mile and a half south of Cave Spring, the mineral is also reported.
Northeastwar<.l, about six miles. from Cave Spring, both the reel and the whitish mineral occurs on the laud of Mr. John Henry, lot 910, :3d district. This is on the west side of the ridge and exposed by washouts descending the hill (see analysis). Much ore is shown upon the surface.
At a short distance to the north, is New Prospect church, and back of it, on lot 820 (Mr. Myles Mosley), is a light gray, earthy looking mass, with concretions of beanxite, beneath from two to four feet of gray soil. This is near the western foot of a ridge on which are iron and manganese ore'3. Indeed, near the beauxite, a siliceous iron ore is seen.
On lot 534, 3d district, is the deposit of Mr. A. W. Bobo; it lies in a cove on the eastern side of a ridge. It is a mixture of gray with some white and red beauxite, and much clay is associated with it. The grade is high (see analysis). It has been profitably worked. On properties near by, other deposits (Mrs. W. S. Johnson's, lots 692 and 677) are reported, and extensive deposits of iron ore have been worked on adjacent lots.
Upon the eastern side of a ridge1 cast of the last named, Mr. J. A. Howell's land (lot 610 or 615) contains beauxite in a cove, and also large deposits of brown ore.
On lot 906, 3d district, Mr. Doyle'r; farm contains beauxite (see analysis). This is in the valley, and may be only float. It lies on northwestern side of another ridge. To the east, Mr. Scott's farm,
lots 897 and 960, :3d district, now owned by Mr. J. vV. Hawkins,
contains the white and red mineral, occULTing on the lower part of the ridge and covered with more or less creep soil. On the side of
u: .valley eastward, beauxite occurs on property of Mr. R. S. Brammon
(lot 22d district). Upon the western side of a ridge, east of the C. R. & C. Railway, Dr. J. C. Reece has much light colored

228

ECONOMIC RESOURCEH.

beauxite on lot 60, 22d district. This occurs on the western side of a ridge. This land here is gray, with very little chert.
In this district we thus see that the beauxite occurs on numerous parallel ridges, extending from Polk county northward to near Hilver creek. Indeed, there seems no reason why the mineral may not be found nearly all the way to the Etowah river, along the more rugged western portions of the Knox dolomite series, west of Spring cteek valley. Some beauxite ha;, been reported east of this stream, but the existing conditions are different from those farther west.
Northeast of Rome the beauxite belt reappears, as on the lands of Mr. Wisnant and Mr. Walters and other properties. The belt continues northeastward, and is extensively developed near Herlllitage. This is the localtiy where :Mr.J. W. Hawkins first found it in.1887. More than 4,000 tons have been taken out of a pit on lot 61, 23d district (to October, 18Hl). This pit is more than 100 feet in diameter and 50 feet deep without reaching the bottom of the deposit. The beauxite is of red and white colors, the different varieties prevailing in different parts of the pit. It occurs in nodules and bouldere made up of concretionary pisolites, bedded in an earthy mass. Or, again, it may be in the form of loose gravel-like masses, in which case it is apt to be silioeous. One of these boulders yielded <>ixty-four wagon loads. At this digging more or less earthy mineral and clay bands oceur along with the beauxite or between the pockets. Also horses of clay prevail in the pit, so that more than half of the material has to be rejected. Much beanxite is lost with this refuse. The redder mineral seems to prevail in the lower parts of the accumulations.
The deposit is covered with from four to eight feet or mote of light tinted red clay. Some of this surface covering is probably of creep origin, as it occurs on the side of a ridge. The surface is strewn with some cherty fragments. The beauxite here appears to be in great lenticular pockets:1peculiar to certain beds of the origi-

ALUMINIUlli ORES.

229

nal rock. The bedding is mostly obliterated, but some bands of red clay, dipping southeastward, indicate the relation to the original bedding. The locations of the beauxite are near the head of the cove in the ridge. In another opening on the same property the white clay also prevails. Boulders of beauxite are occasionally scattered through the clay beds.
On Flowery branch, lot 21, 23d district, light colored beauxite and white clay occm on the gently rising ridge. (See analysis of clays.)
In this region beauxite occurs on many other propertie,.:;; and is said to be found on lots 22, 19, 30, 39, 103, 104, 147, 134, 136, 23d district, by Mr. J. W. Hawkins.
The ore of this region is shipped from Cunningham station. There are many iron ore deposits in this (Armstrong Mountain) district, which are more or less associated with the superficial cherty accumulations. Northeast of these deposits the beauxite is found on Mr. Shaw's fatm, lot 31 (?), 16th district, about two miles south west of Adairsville. Here the mineral occurs as boulders in yellow clay. In descending into the mass the pisolitic grains become fewer. At the surface it is a light L'eddish mass, with the interior of the grains dissolved away, and the partial cavities containing a light reddish powder (see analysis). The situation of the deposit is on the west side of a flattened ridge. This chain of deposits continues to the border of Gordon county. In a coye on lot 32, 15th district, on property of Mr. J. M. Pinson, there is a large deposit of the white mineral, but it has not been analyzed. West of Linwood (late Hall's Station) beauxite occurs on the Barnsley estate (lot 115 and others in the 16th district, Bartow county) at ~Woodland. It is found in large boulders beneath a yellowish, sandy clay soil; on a flattened and also on more rugged ridges. H is a light colored, in part compact pisolitic mass of high grade (sea

230

ECONOMIC REF:IOURCEH.

analyses), and again in loose oolitic gravel. Iron and manganese ores occur near by. On the east side of the valley there are oth~r deposits of high grade, which contain gibbsite. Large exposures may now be seen since the removal of three to fiye feet of soil.
Other ridges to the eastward contain large deposits of beauxite. On the ridge to the westward of the Connesenna creek, near Cement, beauxite occurs in yellowish reel clay beneath yellowish soil, covered with only a small amount of chert, although the ridge is generally cherty. An example may be seen in the deposits of Montague & Co., lot 97, 16th district. Woodland is in a narrow valley excavated out of Upper Cambrian slates. Beyond, various ridges contain beauxite, as lots 107, 108, 109, 102, etc.
Eastward of Linwood some of the propetties show large deposits, as that of Mr. Seay (lot 108, 16th district). This beanxite is whitish, oolitic and porcelaneous in places. Other deposits are reel. On lot 108, the mineral is covered with from six to nine feet of yellowish soil. There are extensive iron ore deposits in thi~; l>ame region.
In the Knox series in the eastern part of Bartow county, beauxite also occurs, and at many other localities in the formation it may likely be found. The Bobo, Hermitage and Barnsley deposits are those where the principal workings are located. At other localitie~; in northwestern Georgia, beauxite occurs upon the narrow belt of Knox dolomite associated with white clay and sparingly with brown iron ores. Thus heauxite ii'O found on a lot of Mr. Taylor, west of Summerville. Elsewhere, in the narrow belts of the formation, bea uxite may be looked for, as well as in the broader belts of the Coosa basin.

ALU)IINVM.

231

CHAPTER XXXIII.
ALUi\fiXUi\f, ITS SOURCES AND "C"SES.
BY R. L. PACHARD.
FROM AUTHOR'S SHEETS 01' "MfNERAL RE30URCE3 OF THE UNfTED STA'.rES FOR 18nl."
NoTE.-Owing to the rising importance of aluminum iLnd its sources of supply, the editor hfls deemej it advis~tble to !tppcnd the paper to th11t ol this report of the survey of the State as it was only received after the Georgia report was iu type.
BAUXI'rE fN El:ROPE.
"The mineral received its name from Baux, a village in the south of France, where it was first found, and the more highly ferriferons variety was regarded and worked as an iron ore, but proved too refractory. It sometimes ran as high as -!2 per cent. metallic iron. The analysis by Berthier revealed its true character. The geological occurrence of the bauxite of Baux was studied by H. Coquand (Bttll. de la Societe fieologique de F'I'Ctnce, vol. 28, p. 98, 1811), wl10 describes the mineral as of three varieties, pisolitic, compact and earthy. The pisolitir. variety does not differ in structure from the iron ores of Franche Comt6 and Berry, although the color and composition are different. It occurs in highly tilted beds alternating with limestones, sandstones, and clays, belonging to the upper cretaceous periods, and in pockets or cavities in the limestone. The limestone containing the bauxite and that adjacent thereto is also pisolitic, some nodules being as large as the fist, and pisolitic bauxite has sometimes a calcareous cement, and at others is included in a paste of the compact mineral. i\f. Coquand supposed that the alumina and iron oxide composing the bauxite were brought to the ancient lake bed in which the lacustrine limestone was formed by mineral springs, which, discharging in the bottom of the lake, allowed the alumina and iron oxide to be distributed with the other sediment. In some cases the discharge occurred on land, and the deposit then formed isolated pat'Ches. He refers to other similar deposits of bauxite of the same period in France. Sometimes the highly ferriferous mineral predominates over the aluminous (white), at others diaspore is found enveloping the red mineral, while in others it is mixed with it, predominating largely, and sometimes manganese peroxide replaces ferric

232

ECOKO"MIC RESOURCES.

oxide. In some places the ground was strewed with fragm ents of tnbero.us menilite, very light and white.
l\1. Ang~ (Bull. Soc. Geolog. de France, 1G, p. 345, 1888 ) describes the bauxite of Var and H~rault and gives an alysis of it. Over 20,000 tons were being mined in this region annually at the time of writirlg his report (1888). In the red mineral of Var druses occur with white bauxite running as high as 85 per cent. Ah03, and 15 p er cent. H zO, corresponding to the formula AlzO g+ HzO. He refers to the prevailing theory of the formation of bauxite, according to which solutions of the chlorides of aluminum and iron in contact with carbonate of lime undergo double decomposition, formin g alumina, iron oxide , and calcium chloride. Other deposits in the south of France , in Ireland, Austria and Italy, he says, confirm this view, because they also rest upon or are associated with limestone. The bauxite deposit in Puy de Dome which he studied could not, however , be explained by tt.is theory because it was not; nssoniated with 11rn estone, b uL rested dhectly upon gneiss antlwt\s J~tUtly ove1ed by bas(llt. Til geological s keLcb mnp of t be deposit Jlear 1.adl'i11.t, I' uy de Dome, wh i h he gives. shows gne~ss, llasa1t witla uncovered bau.,..dte lm:gely predomi nating, and pntcheF.> of miocen e clays, while a geoJoical section o( the lepnsit. 'rl s(tr Yill vey n tc, H mnlt, shows the 1 ed o[ bauxite conformably following the flexures of the limestone formation when covered by more re en t l1ed , Rnd wl1en exposed and denuded occupying cavities and pockets in th e li mestone. This oc urren a is substantially the same
as that of the neigh borin" Buux. 1\f. Ang6 agrees with l\1. Coquand in at-
tributing the bauxite to geyse11ia n origin . 1-[e uses as nn illustration of the contemporaneous formation of ],)auxite the deposits from the geysers of Yellowstone park, which is evidently due to a misunderstanding. He made no petrographical examination of the bauxite of Puy de Dom e, nor did he
attempt to trace any genetic relation between the latter and the accompanying basalt . The occurrence is, however, noteworthy, and an examination might show that it is another instance of the direct derivation of bauxite from. basalt, which is m aintained in the two following instances, somewhat imperfectly in the first 1!o be sure, but with greater detail in the second.
The first is a paper by Lang in the Berichte der Deutschen Ohemischen Gllsellschaft, Vol. 11, p. 2892, 1884. He describes the bauxite in Ober-Hes-
sen which is fotm d in ~he :flolda i u ouncl mfl B e$ up to the size of o. man's heat! , embedrl d in a clay wbich is colbred with iron oxide. The composition var ies ve1y wido ly. The 1etrog1aphical examinnti.on sh we l s ilica, iron oxide, m agnetite, a nd augi te. The hemicaJ composit ion and J etrograph ical
exarrrinntiou shoWB tl e bau.'< ite to be a decomposition prod uct o( basttlt. .By the weatl ering of t he plugiodase ieldspars, aug ite, and ol i vin , ne ndy rtll the ~:~i llca h~d l)een ,removed, to ether with t he greater 1an of the li me ani.l magnesilt; the iron huu been ox ldi;~etl nm1 hydrn.te of alu LDinn forme d as shown

ALUllliNUM.

233

by it~ easy solubility in hydrochloric acid. 'l'he residue of the silica had crystallized as quartz in the pores of the mineral.
'fhe more detailed account of the derivation of bauxite from basalt is given in an inaugural dissertation by A. LiebreicH, abstracted in the Chemisches Cent?albl(ttt, 1892, No. 3, p. D4. This writer says that the well known localities of ba~xite in Germany are the southern slope of the '\Vesterwald near Miihlbach, Hadamar, in the neighborhood of Lesser Steinheim, near Hanan, and especially the Western slope of the Yogelsherg. Chemical anal?ses show certain differences in the composition of bauxite from different places, the sm'aller amount of water in the French bauxite referring it to diaspore, while the Vogelsberg mineral is probably Gibbsite (hydrargillite). The bauxites of Ireland, of '\Yesterwald, and the Vogelsberg, show by certaiN external indications their derivation from basalt. The bauxite of the Vogelsberg occurs in scattered lumps or small masses, partly on the surface and partly imbedded in a grayish white b reddish brown clay, which contains also similar masses of basaltic iron ore and fragments of more or less weathered basalt itself. Although the latter was associated intimately with the bauxite, a direct and close connection of the two could not be found, but an examination of thin sections of the Vogelsberg bauxite sh.:>wed that most specimens still possessed a basaltic (aname>ite) structure, which enabled the author to determiue the former constituents with more or less certainty. The clay from different points in the district carrying basalt, basaltic iron ore, and bauxite were examined, some of which showed clearly a sedimentary character. Some of the bauxite nodules were a foot and a half in diameter and possessed no characteristic form. They were of an uneven surface, light to dark brown, white, yellowish, and gray in color, speckled and pitted, sometimes finely porous and full of small colorless or yellowish crystals of hydrargillite. The thin sections showed distinct medium-granular nnamesitic structure. Lath-shaped portions filled with a yellowish substance preponderated (the former plagioclases) and filling the spaces betiVeen these were cloudy, yellow, brown, and black transparent masses which had evidently taken the place of the former augite. Laths and plates of titanic iron, often fractured, were commonly present and the contours of altered olivine coulrl. be clearly made out. The anamesitic basalt of the neighborhood showed a structure fully corresponding with the bauxite. Olivine and titanic iron oxide were found in the clay by washing. The basaltic iron ore also showed the anamesite structure.
BAL'XITE IN AMERICA.
The American occurrences of bauxite so far observed are in Alabama, Georgia and Arkansas. Prof. Eugene A. Smith, State Geologist of Alabama, has kindly furnished the following information in regard to the bauxite of that State. He writes:

23 4

.ECON<UIIC RESOURCEB.

IN ALABA~IA.

"The mining of bauxite was begun in Alabama in November, 1891, by the

Southern Bauxite :Mining and ,Manufacturing Comp any, of Piedmont, Ala-

bama, which h as shipped up to date ( November, 18U2J abont 3,GOO tons. In

July, 1892, the Republic Mining and Manufacturing Company, of Hermitage ,

Georgia (which is the pioneer in the business), secured a lease of the mines

ot' (.h I nss F mn.tu)e omprmy, at Roc! R u.n, ' betokee cou n ty, and has

shipped up to <late, nbout 1,300 tons. I n a hlition to th is oth companjes

have severnl 'bu nw d tons UJJde.t sheds rhyiJ:u: out. 'l'he ore goes l:o r hil a-

delphln ttud "ntrona, P ennsy lvania; Syra n e, Bu.ft':ilo, Jl ro k lyn, New Yo rk,

* and e t)let p lnces. -:f

-:t Lt, comes into c tnpetition wit.L (ll'e from

Baux in France, which can be pnrchased at a lower price than that at whi ch

this region can furnish it; but it is claimed by the manufacturers that our ore

is more solub le, and therefor e more valuable, tllough containing elightJy less
(Ll mni rla.. * * ( tn] nlu:miun rtma from ;;u pel' cent. to l.iO per (:eu t. avernge

l!ltdo:ld r~nl\'l yais. f the insolu ble m atter sillctt is the h ief in gredient.

The re ont1~ins 1. Lo 3 pe1 eM b. o-r titO:nic acid, and will t1 vera <Y

from 25 per cent. to !llJ per cent. l water . ' l1e or o t ns asso inted

with limonites and kaolins in irregular beds, in the region underlaid by

the Knox dolomite of the Lower Silurian formation. In Alabama these

occurr ences are always near to the foothills of the n1.ountains formed of

the '\Veisner quartzite or sandstone, which is a member of the Cambrian

in this State. The bauxite therefore seems to be associated chiefly with

the lower beds of the Knox dolomite. The best known occurrences are

near Rock Run furnac e in Cherokee county. where it has b een follow ed for a

few miles toward the Georgia line . This is the only place in Al abama where

any systematic mining is done, and this by the two companies above named

whose mines are closely contiguous. Near J acksonville, Alabama, in Cal-

houn county, the ore has also been discovered, but not yet mined commer-

cially .

"The mines are inS. 2), T. ll, R. 11, about three and a half miles nort.h-

east of Ro ck Run furnace nnd close to the Georgia line . In mining the lim-

onite in one place great quantities of bauxite were m oved and lie no"': in the

clump pile. This was before it was r ecognized as baux ite."

The statistical information in the foregoing was furnished to Prof. Eugene

A. Smith, State Geologist of Alabama, by l\'lr. J. M. Garvin, superintendent

of the Rock Run Furnace Company.

He sends analyses, which are included with the others on a subsequent

p age.

I N GEOR GIA.

The Georgia baux ite occurs in the same formation . The Bureau is in-

ALUMINUM.

235

debted to Dr. J. "\V. Spencer, State Geologist of Georgia, for the following

account of its occurrence:

"It occurs in the residual clay from decomposition of the Knox (calcifer-

ous) dolomite formation, which series is greatly developed in Georgia. The

principal belt commences near Adairsville and widens out, extending in a

southwestern direction to Alabama. It occurs in the vicinity of brown iron and

manganese ores. Indeed, the bauxite-bearing portion of the Knox series is

nearly coincident with the manganese deposits. It occurs in pcckets, often

of great extent, and is usually covered with a few feet of clayey surface. A

kaolin is often associa,ted with it. It is mostly in concretionary nodules

forming large pocket.s of small kidney-shaped masses scattered through the

clay. Much of the bauxite is light colored, but other portions contain much

iron. At one locality Gibbsite occurs associated with it. It evidently has a

similar origin with the brown iron or manganese ores, and was probably de-

posited in lagoon9 from solution of decomposed crystalline rocks, which occur

18 or ~0 miles to the east. Alumina is slightly soluble in water containing

CO2, as are also the other metals." The analyses of the Georgia bauxite by

Prof. H. C. White are given below.

An estimate of the quantity of bauxite mined in Georgia, furnished to this

division by Mr. Wm. G. Neilson, of Philadelphia, gives 728 tons for 1889,

1,850 tons for 1890, and 3,300 for 18\Jl. 'fhe total output for Alabama up to

June, 1892, was 3,200 tons.

The Arkansas bauxites occur in Tertiary areas and in the neighborhood of

eruptive syenites, to which they seem to be genetically related. The mineral

is pisolitic in structure, and varies in color and chemical composition (analy-

sis below). It has been mined for iron ore, some specimens yielding 20 per

cent. metallic iron, and is of great abundance (Prof. J. C. Branner, American

Geologist, VII., p. 181).

Having now traced the ore of aluminum to its origin, as far as present in-

formation will allow' the following analyses will show the wide variations in

its composition.

(For analyses foreign and Georgia bauxite, see Chapter XXXII.)

*

*



236

ECONOMIC RESOURCES.

ANALYSES 01' ALABA~1A BAUXITE . [Analyst, Dr. Wm. B. Phillips.]

From Cherokee county.

Jacksonv-ille,
Calhoun county.

Jacksonville,
Calhoun
count)T,
red.

Jaoksonvllle,
r.alhoun county. white.

.'I " ............................. ....................... ....... .....
ffi~~;\~i~~:~~~;~:~~~-: :~: ~ ~~: : ~:~ : ~~: :~ :~:~: : : :;: :
TJ O ~ ..........,....... . ........ ................ ......... ......... .

Per cent. 37.87 39.44 2. 2i 9.20
12..80

Per cent. 18.67
45.94 11. 86 1. 40
2UO

Per cent. 7.73 47.52 19.95
} 23.57

Per cent . 23.71 41.88 .85
23.41

ANAL YS ES OL' BAL'XITE FRO~! ,JACKSONYILLE, CALHOUN COUNTY, ALABAMA. [Analyst, W. F. Hillebrand]

Red.

White.

Per cent. Per cent.
~~!ift.~;~ ~ .;;!~~: :: ~i::;=.:~-~:~:.:~ :,; ~:__T_~_!_0~.!:-i_-T_;_!_0:_~_;

Total......... ........................ .............. ............. .. ...... ...... ...... .... . ...... 100.11 CaO, MgO, and alkalies, not looked for.
BAUXITE FROM PULASKI COUNTY, ARKANSAS .

98. 62

Black.

Red.

Per cent.

810~............. ..... ... ...... .... .......... ....

10.13

~!~8~::::.-.-.-.-.-.-.-~.-.-.-.-. ::::::::::::::::::::::::: 5~:8~

H 2 u............................ .................. 28.99

Per cent. 11.48
5i:~~ .
28.63

Per cent.
ru;5.11
17.39

Per cent. 4.89
~~:~g
26.68

Pe1 cent. 3.34
5~:n
28. 63

Total .. ............ .................... - -1-0-0-. 7-9-l' - -9- 9-.-56-l---!,-7.-84-+- -10-0-.1- 2- l - - -99___6_8_

Per cent. Per cent. Per cent.

: : : .: : : : : : : : :: : : : :_: _: _:,: : : : ::-: : 810~..................... ................... ...........................................

2. 00

t~~?.~::: ::~:-:-::-: ::~::::

::::::~--~ G~:~8

10. 38 50.64
1. 95 3.50

16. 76
51.90 3.16
3.50

1 1. 0 (1;{1.1. 1.................................. .......... ........... ..................... 30.31

27. 62

24.86

Total. .................................................... .................... 1 --"9'9"'.-5=-2=--l-----9,9,..0.~-,:-::-J-U1I)-.:-!.='l~~



ALU.UINUU.

237

METALLURGY.
The electrolytic process by which aluminum is extracted from its oxide, alumina, is now well understood by all persons interested in the subject. In this country it is carried on by the Pittsburg Reduction Company. The principle is that alumina is decomposed in the presence of a melted fluoride by the electric current, and metallic aluminum is liberated. Powerful dynamos fnrnish the current for this purpose. In practice the alumina is dissolved in the fused flux, consisting of fluorides of aluminum and sodium, which is regarded as serving as a vehicle for the alumina. The furnace for effecting the operation is made in the form of an open iron-cased box which is thickly lined with carbon and is provided with a spout at the bottom for tapping of the aluminum. A large block, or series of bars of carbon, carried on an adjustable support and arrDnged to dip into the center of the fu:rnace, forms the anode, the furnace itself forming the cathode. After the flux and alumina have been introduced the carbon anode is brought well down into the furnace and the current turned on. At first considerable resistance is offered, but as the materials in the furnace become highly heated this decreases, and the anode can be raised somewhat. Decomposition soon begins, the alumina being resolved into oxygen and metallic aluminum, the former being liberated at the anode, and, combining with the cH.rbon of which it is composed, passes off as carbonic oxide, while the metallic aluminum, being heavier than the melted bath, sinks to the bottom of the latter and is tapped off from time to time. As the alumina is used up the increase,in resistance indicates the progress of the reduction, and fresh alumina is added. The operation therefore is continuous.
Several new processes were patented during the year 18!Jl in Europe and in this country, the published character of which describes variations (improvements) on those already well known. It would be without the scope of this report to describe these processes until there is evidence to show that they have been put in operation in this country. The Pittsburg Reduction Company and the Cowles Company were the only producers in 1891.
PRODUCTIONS.
The amount of aluminum produced in this country during 1811, including small experimental concerns and that contained in alloys, amounted to 150,000 pounds. The Pittsburg Reduction Company's plant was in operation only five months of the year, owing to its removal to Kensington. In the pre:.:eding yem the production was 47,881 pounds; and in 188U, 19,200 pounds.
In 18S!) it was estimated that the total amount of aluminum extracted up to that date was about 116 tons, but that the indications then were that the. annual pl'oduction would soon exceed that amount. This prediction has been more than verified. The Neuhausen Company was producing at the

23 8

ECOKOJ\IIO RESOL'RCES.

rn~e of 1,000 kllOB n luy ~~~ t.h e cloaa.of I UJ.. (Dingl 1', ::! 2, 2 p. 43 1.) A b ru nch oi this company at Fuges procluces tthout -100 k il s la ily n.u c.l Ill togethe r it. is an.le t;o S~.ty that. over .500 tons of nlu.minum m:e being pr ocl n etl annuall y iu t his country und E nrope . Although the A.ru.e l'ican lll'Od nc:tion luis 11ean fn r ou tstrip ped by th a.lil lll'opean , th er e ttve indicntion s that t.he yeRI' 1A~)2 wi ll s how a u im pi'OV me.nt in thi.tl indtl Lry in tlri s otmtry .
!'RICE.
In the United States the price of aluminum ranged from 15 cents to no
cents per pound, according to quantity. At the beginning of 1HH2 it was quoted at 50 cents wholesale in the market reports. The European price was 5 marks per kilo at the latter date.
USES.
Besiles the metali mgical use of al umi num i 11 casting iron ~mu stee l, to b
r!l ferred to bel '" tl.te .m et.nl is used r r lll1 inJiui ty or small 1\rticles as h a s
a lWll-YB been th case a nd !o1 whi ch its lightn ess st.rengLh , and free ~om from ta rn ish eminen t ly a 'IILpt ib. litdee , with a tota l prod uction of betw en 5 0 and UOO to n.s, of which, perhaps, fj{)Q 01tly are twaill~ble f r m,anu(a 'tlll'e I articles, no extensive use on the large scale could b e expected. The newspapers have fre quently spoken of the Swiss steam launch of aluminum. "~ life-boat of aluminum was under cons truction at Stralsund, Prussia., in December, 1801. It was expected that tbe lightness of the metal would be of great ndvnntsge iu dr1>gging the boat over the sands and in hoisting and loweri.ng it. Th e Jist of pr oposed uses continue to increase. Disregarding them, tho actual liB ia su fll.ciently varied. Small articles, viz., drinking cups , rul ers and 11aper-cutters, perfumery stands, smokers' sets, ash-receivers, to thp.i k Hud ma tch holders, watch caMs. 1 monade shakers , card receive 1s, butter tlishes, rings , spo ne, p icture fra111es, bracelets, napkin rin gs, sleeve 1\nd collt\1' buttons, scad and s ha wl pi ns, pe.m acks, dog coll ars , key chains, haiiI ills, penil cases , a u lrnll \ni ld n s 1Ue ndv r tis ed.
In Germany aluminum tubing is used for penholders, umbrella handles, walking sticks, billiar d cues, chair legs, photograph frames, <tnd newspaper holders.
Powdered aluminum mixed with chlorate of potassium has been used for flashlights instead of magnesium. It is said to make an excellent light and to give no smoke like magnesium.
Lr. .c\.H.recl E . Runt, p l' aident of the P itts burg Heduction 'out pany in a, lec) tme d eHvel'e I iuMnJc iJ , I,'!H, gives strme i.nforn111.tion in re"Rr d to t he nee f Hl nm inrun .in rnilroa 1 work. He Sltye l.h nt l.be met a l h!lS IJeen used 011 RCCOUU't IF its l ightness, fO r slid val r es ((l:xpedme.ntally ) i for valves to COli l rol the pn.asage of the tt.ir I1'om tho stoage to the brake cylinde rs in then w
nnd iar gel' ims or the IVe. tin house air brn ke, U1e ine rtia of the h etn-y

ALUl\HNUl\I.

239

iron or brass valves being a serious consideration; for the fan blades and frames of windmills; in semaphore signal disks and their moving frame work.
The use of aiuminum for canteens and military equipments in the German army has suggested a similar use in this count.ry, and aluminum curb bits, saber-belt plates, canteens, meat cans, cartridge-belt plates, and spoons and forks have been submitted to the \Var Department in \Yashington for consideration. The object is to save weight and avoid rust.
The substitution oE aluminum for glass flasks for the army and its use in general for vessels which are designed for holding foods and drinking fluids have given rise to experiments in Germany to test the action of various flui(ls upon the metal. The results are on the whole favorable to its employment for such purposes. It must be remembered that the aluminum of commerce contains small quantities of other metals and metalloids, sometimes amounting to 2 per cent., so that it is virtually an alloy. The resistance of aluminum to acids has long been a popular belief, and, before giving the results of the experiments as to the action of drinking fluids upon aluminum, the following account of some experiments with nitric and sulphuric acids is given to show that the former belief in the resistance of the metal to all acid except hydrochloric must be modified. Undoubtedly the physical condition of the metal operated on, as w:ell as its chemical composition, makes a great difference in its power to resist the action of acids, a finely divided metal being much more easily attacked than the same metal in large pieces. G. A. LeRoy (Chemisches Centralblatt, 1892, Ed. I., No. 2, p. 51) found that nitric and sulphuric acids of different strengths acted upon aluminum as shown below under the condition;; specified. He used aluminum foil having the composition 98.29 per cent. to IJD.o per cent. aluminum, 1.60 pEc>r cent. to 0.30 per cent. iron, and 0.10 per cent. to 0.25 per cent. silicon. The foil was polished, freed from fat with caustic soda, washed with alcohol, dried in the bath, cut up, weighed, and introduced into the acids. In this fine condition the action of the acids was as shown in the following table, the weight being the amount of metal dis9olved expressed in grams per square meter. The action lasted twelve hours.

2-10

E CONOMIC RESOURCES.

ACTION OF VARIOUS ACIDS 0:-1 ALlDIINU)I FOIL.

ACIDS.

~ ~. Temper-

Sample~.

a .= a.ture

~ f (centi-

'.11 EO grade.)

A.

B.

C.

D.

- - -- ---:------- - -- - --

Grnms. G1ams. Glams. Gl'a?ll~.
15-20 ts.io 1s . oo 16.40 H.:.o

} [) C-2QO 21.00 21.80 17.50 16. 40

15o-:zoo ~4.50 2!\ . 00 2~.00 20.00

15-20 ~5.80 2:\ , 70 24.60 22.40

] 50-200 19.00 lH. OO 17.\JO 16.30

... 1U8 i.o:oo 15-20
15-20

1~:gg

,~:gg

J50-2QO 29. 50 1\). 60 18.00 16. 60

15-20 l6.:JO 16. 30 H.OO 13. 40

150 240 . 22~. 1!i0. 200 .

no 150 267 .

250.

~10.

220 .

J.OO" ..... ......... .... . } Vi o l nl Vll'l l

100'' .. .... .. ... ......... !Lc.l.!nn. u.cWuu .

According to these results almoHtpure aluminum, \HJ.,5 per cent., is attacked even in the cold by nitric and sulphuric acids , so that the metal Hhould not be used in apparatus for preparing these acids.
As to the action of drinking fluids, coffee, tea, beer, wines, brandy, etc., the following appears to be the state of the case: Messrs. Lii.bbert and Roscher, Chern. Cwtmlbl., 1891, Ed. II., No.18, p. 780) tested the resistance of aluminum to the action of alcohol, ethe r, ald'lhyde, coffee, tea, wines and antisepticH, by allowing aluminum leaf to remain in concentrated solutions of the different liquids four days at the temperat ure of the room, and the fluid s were examined either directly for alumina or were evaporated and the ignited residue so examined. Thb conclusion reached was that aluminum possesHes only a slight degree of resistance to the agents named, except alcohol, ether and aldehyde, and that it is therefore ummitable for wares which are to be used for acid drinks, coffee, tea, etc., or artides which are to be cleaned with soda or Aoap. Its application in daily life would therefore be very limited.
On the other hand, G. Rupp, (Dingler, 283, I, January 21, 1892,) criticizes the methods employed by Liibbert and Roscher for determining the action of the fluids by eHtimating the alumina contained in them, as well as the use of aluminum leaf for their experimentA, which is attacked much more easily than the compact metal, the former being acted on even by boiling water, while the latter is unaffected. His own experiments were made upon aluminum vessels (canteens, drinking cups, etc.) and foil, the object being to determine the availability of the metal for uHe in the army. The carefully dried and weighed vessels were filled with the different fluids or the foil was immerAed in them, and the action was allowed to continue four, eight and twenty-eight da_vs, at the temperature of the room with frequent stirrin g. The fluirls included wines of different kinds, beer, kirHchwasser, P.ognac, coffee,

ALUl\IINUl\J,

241

tea, milk, drinking water, 1 per cent. solution of tartaric acid, acetic acid (1 per cent., 4 per cent., 10 per cent. solutions), vinegar (10 per cent.), soda solution (1 per cent.), besides butter, honey and preserved fruits. The articles were then cleaned, dried and weighed, to determine the loss of weight. The results, which fill a large table, flhowed that in most cases there was absolutely no action and in the few cases where there was a perceptible loss of weight it was flO trifling as to be disregarded. To the objection that continued drinking of fluhls containing a small quantity of alumina would eventually be dangerous, the author points out that thte ash of all the fluids usually drank contains alumina, as well as most foods and drinking water itself. His conclusion is that thbre is no objection to the use of aluminum for canteens and similar vessels.
These conclusions of Rupp were confirmed by Dr. A. Arche (D'io.gleT, Vol_ 284, No. 11, p. :255), whose experiments show that the purity of aluminum (usii1g the percentage of silicon as a means of classification) has much to do with its power of resisting the solvent action of fluids, and they also show that the mechanical preparation of the metal is an important factor. He found that hammered aluminum was least attacked, rolled metal came next, a'ld then the dra.wn metal, while cast metal was much more easily attacked (by acetic acid).
ME'rALLURGICAL USE.
The quantity of aluminum used in this country in the manufacture of iron and steel castings is probably from2i) to 30 per cent. of the total production. In Europe it is estimated by Professor 'Vedding to be 5.Jc per cent. This use, as was explained in the last number of this series, consists in adding from 0.10 to 0.15 per cent. of aluminum to iron or steel just before casting, by which blow-holes are prevented and sounder casting are produced. This u;;e is becorning general. The beneficial effect, as was shown by experiments referred to last year, is due in part at least to the deoxidizing action of aluminum upon carbon monoxide at a high temperature, a reaction which was demon,;traterl directly between the metal and the gas. This subject has not yet received an exhaustive examination. For this purpose it would be necessary to know the composition of the iron or steel operated on in each case and make comparative tests on the different specimens. It is also probable that the method of melting employed has an effect on the result.
A detail of manipulation in the method of applying aluminum, especially in castings for steam and pump cylinders and other castings intended toresist high pressures, is reported in Dingler's Joumal (Vol. 284, No. 11, p. 255). The addition is made by first forming a mixture of aluminum and iron, which is effected by placing the proper quantity of heated aluminum in the bottom of a small ladle, running some iron into the ladle from the furnace, and waiting until the mixture begins to stiffen. Then the iron to be operated on is
(lG)

2-!2

ECONOMIC RESOV RCEH.

run into a large ladle and the iron-aluminum mixture is poured into it, whereby an intimate mixture of the whole is effected. For 100 kilograms of iron to be operated on :200 grams of aluminum are used ( =0.20 per cent.) The iron is not poured at once from the large ladle, but is allowed to stand until it is orangey ellow and a thin film begins to form on the surface. As soon as this occurs the film is removed and the iron is poured. The mold should be kept full. No reason is assigned for this procedure, but it appears that iron containing aluminum is inclined to shrink excessively and that this tendency must be obviated by pouring as cold as possible.
According to a paper read by Mr. .T. w.I,angley, at the Gleu Summit meeting oi the American Institute of Mining Engineers, the practice in the United States in pouring ingots is as follows: The aluminum, in small pieces of _!i
or H pound weight, is thrown into the ladle during the tapping, shortly after
a small quantity of steel has already entered it. The aluminum melts almost instantaneously and diffuses with great rapidity throughout the contents of the ladle. The diffusion seems to be complete, for the writer has never seen the slightest action indicating want of homogeneity of mixture, all of the ingots poured from one ladle being precisely alike so far as the specific action of the aluminum is concerned. The quantity of aluminum to be employed will vary slightly according to the kind of steel and the results to be obtained. For opened-hearth steel, containing less than 0.50 per cent. carbon, the amount will range from 5 to 10 ounces per ton of steel. For Bessemer steel the quantities should be slightly increased, viz., 7 to 16 ounces. For steel containing over 0.50 per cent. carbon, aluminum should be used cautiously; in general between 4 and 8 ounces to the ton. If these statements are put in the form of percentages, it will at once be seen how extremely minute is the quantity of aluminum which causes such marvelous results, for the num-
bers are :

4 ounce5 = 0.0125 per cent.. .. ...... . .............. = 1-8000

5 ounces = 0.015(i per cent. .

= 1-().500

8 ounces = 0.0250 per cent. ..... , H\ ounces ~ 0.0500 per cent. . .. . . . . . . .

= 14000 = 1-2000

SOLDERING.
From the articles which occasionally appear in the trade journals, both in this country and Europe, and the patent list, it appears that the difficulties of soldering aluminum have not been overcome. Some of the new solders are introduced here without comment.
Chloride of silver has been recommended as a solder. It is to be finely powdered and spread along the junction to be soldered and melted with the blow pipe. Mr. Joseph W. Richards makes an alloy of aluminuml part, zinc 8 parts, tin 32 parts, and phosphor-tin, containing i) per cent. phosphorus,

ALUJ\IINU!Il.

243

1 part. The aluminum is first melted, then the zinc is added, and finallv the tin, which bas been u!elted separately and mixed with the phosphor-tin." The nlloy is poured into small bars for use. The object is to provide in the phosphorus a powerful reducing agent to prevent the formation of the film of oxide which mmally prevents the intimate contaq_t of the opposed surfaces. (United States patent 407780, October 5, 1891.) Another formula is, cadmium 50 parts, zinc 20, tin 30. The r.inc is first melted, then the cadmium is added, and finally the tin. (Dingler's Jou.mal, Vol. 284, No. 6, page 144.) Electroplnting the surfaces with copper and then applying the solder was mentioned last year.
Other solders which have been uAed are composed of-
COMPOSITION OF CERTADI SOLDERS FOR ALUMINtTM .

I.

n.

III.

IV.

\',

Per ern/.. Per cent. PeceHt. Pel' cent. Pecent.

~A:nlruJ:m: .irn.~u: :m:: :

..
::.: ::

:::::: ~

::

::::::

::;:::::::::::

12 M
80

9 G 85

7 5 88

G 4
90

4
~
94

In making these solders the copper should be melted first, the aluminum then added, and the zinc last. Stearin is used as a fiux to prevent the rapid oxidation of the zinc. When the last metal is fused, which takes place very qnicldy, the operation should be finished as rapidly as possible by stirring the mass, and the alloy should then be poured into an ingot mold of iron, previously rubbed with fat. The pieces to be soldered should first be cleaned thoroughly and roughened with a file and the solder placed on the parts in small fragments, the pieces being supported on a piece of charcoal. The place of juncture should be heated with the blast lamp. The union is facilitated by the use of a soldering tool of aluminum. This last is said to be essential to the success of ~he operation. Alloy I. is recommended for small objects of jewelry; alloy IV. is said to be the best adapted for larger objects and for general work, and is that most generally used. The successful performance of the act of soldering appears to require skill and experience, but 'the results obtained are said to leave nothing to be desired. Soldering tools of copper or brass should be avoided, as they would form colored alloys with the aluminum and solder. The skillful use of the aluminum tool, however, requires some practice. At the instant of fusion the operator must apply some friction, and, as the solder melts very suddenly, the right moment for this manipnlation may be lost unless the workman is experienced.
ALLOYS.
It is regretted that no statistics of the production of aluminum bronze and

244

ECONO;'IIIC RESOURCES.

ferro-aluminum in this country can be given for 1891. Both of these valua-

ble alloys have been produced by the Cowles Electric Smelting and Alumi-

num Company for a number of years, and have found their way into the

market on a considerable scale. The ferro-aluminum made by this com-

pany was used as a vehicle for adding aluminum to iron and steel in mak-

ing sound castings when that method was first introduced. Aluminum

bronze is coming into use in Germany for torpedoes on account of its strength

and non-corrodibility, and for telephone wires. It was estimated that280,000

kilograms would be used during 1892. The 5 per cent bronze has been used

for some time for nozzles of gas motors on account of its non-oxidizable char-

acter, and the 12 per cent. bronze is used for the pins of needle guns, for

which purpose it is said to be better than steel.

The number of patents which have been granted for aluminum alloys,

either where that metal forms a minor ingredient or has small quantities of

other metals added to it for special purposes, shows that experimenting in

this direction is increasing. .As yet much of this experimenting is done with-

out definite knowledge or aim on the part of inventors. Doubtless, in time,

valuable conclusions may be derived from this kind of work, after rigid ex-

periments with a definite purpose or idea have been undertaken. Of alloys

formed with aspedfic purpose in view, that containing a small quantity uf

titanium, and another containing silver, were described last year. Others

are mentioned in a lecture by Mr. Hunt, president of the Pittsburg Reduc

tion Company, whose statements are valuable because they are based on

knowledge and experience. He says:

"The alloys of from 2P,~ to 12 per cent. aluminum with copper have so far

achieved the greatest reputation. With the use of 8 per cent. to 12 per cent,

aluminum in copper we obtain one of the most dense, finest grained, auJ

strongest meta,ls known, having remarkable ductility as compared with its

tensile st.rength. A 10 per cent. aluminum bronze can be made in forged

bars with 100,000 pounds tensile strength, oO,OOO pounds elastic limit, and with at least 10 per cent. elongation in 8 inches. An aluminum bronze can



be made to fill a specification of 130,000 pounds tensile strength and 5 per

cent. elongation in 8 inches. Such bronzes have a specific gravity of about

i .50, and are of a light yellow color. For cylinders to withstand high pres

sures such bronze is probably the best metal yet known.

"The 5 to 7 per cent. aluminum bronzes haTe [1, specific gravity of 8.30 to 8,

and are of a handsome yellow color, with a tensile strength of from 70,000 to

80,000 pounds per square inch, an elastic limit of -W,OOO pounds per square

incll. It will probably be bronzes of this latter character that "ill be most

used, and the fact that such bronzes can be rolled and hammered at a red

heat with proper precautions will add greatly to their use. Metal of this

character can be worked in almost every way that steel can, and has for its

advantages its great strength and ductility, and greater power to withstand

ALUMINUM.

245

corrosion, besides its fine color. With the price of aluminum reduced only a very little from the present rates, there is a strong probability of aluminum bronze replacing brass very largely.
"A small percentage of aluminum added to Babbitt metal gives very superior results over the ordinary Babbitt metal. It has been found that the influence of the aluminum upon the ordinary tin-antimony-copper Babbitt is to very considerably increase the durability and wearing properties of the alloy. Under compressive strain aluminum Babbitt proves a little softer than the ordinary Babbitt. A sample 1Yz inches in diameter by 1Yz high began to lose shape at a pressure of 12,000 pounds. A similar sample of the sam& B abbitt metal without the addition of the aluminum (having a composition of 7.3 per cent. antimony, 3.7 per cent. copper, and 89 per cent tin) did not begin to lose its shape until a compressive strain of 16,000 pounds had been spplied. Both samples have stood an equal strain of, 35,000 pounds. In comparative tests of the ordinary Babbitt metal and the aluminum Babbitt metal, the latter has given very satisfactory results.
"The following alloys have recently been found useful: Nickel-aluminum, composed of 20 parts nickel, and 8 parts aluminum, used for decorative purposes; rosine, composed of 40 parts nickel 10 parts silver, 30 parts aluminum, and 20 parts tin, for jewelers' work; sun bronze, composed of 60 parts cobalt (or 40 parts cobalt), 10 pal'ts aluminum, 40 (or 30) parts copper; metalline, composed of 35 parts cobalt, 25 parts aluminum , 10 parts iron, ;nd 30 parts copper.
"Prof. Robert Austin has discovered a beautiful alloy containing 22 per cent. alq.minum and 78 per cent. gold, having a rich purple color, with ruby tints.
''The addition of from 5 per cent. to 15 per cent. aluminum to type metal composed of 25 per cent. antimony and 75 per cent. lead makes a metal giving sharper castings and much more durable type. "
Mr. A. H. Cowles makes an alloy for electrical purposes consisting of manganese 18 parts, aluminum 1.2 parts, silicon 5 parts, zinc 13 parts, and copper 67.5 parts. This alloy has a tensile strength of 26,000 kilograms and 20. per cent. elongation. Its electric resistance is greater than that of "neusilber," and it is therefore especially applicable for rheostats. ( C!temiker-Zeitung, March 12, 1892.)
Mr. C. C. Carroll makes an aluminum alloy for dentists' fillings, consisting of silver 42.3 per cent., tin 52 per cent., copper 4. 7, and aluminum 1 per cent. It is reduced to powder and then forms an amalgam with mercury. ( U. S. p atent 475382, May 24, 1892).
Mr. Chas. B. Miller has patented an antifriction alloy of lead 320 parts, antimony 64, tin 24, aluminum 2. (U. S. patent 456898, July 28, 1891.)
Mr. Thomas MacKellar has patented an alloy for type metal of lead 65 parts, antimony 20, and 10 parts of an alloy consisting of equal parts of tin,

246

ECONOMIC RESOURCES.

copper and aluminum. The tin-copper-alu:ninum alloy is first melted, the antimony added to it, and the mixture is then added to the melted lead. (U. B. patent463427, November 11, 1891.)
An aluminum bronze alloy contains aluminum 12 to 25 parts, manganese 2 to 5, copper 75 to 85. It is the product of John A. ,Jeancon. ( U. S. patent 446351, February 10, 1891.)
The antifriction metal (Babbitt metal plus aluminum) contains antimony 7.3 parts, tin 89, copper 3.7, with from~ to 2.5 parts of aluminum. It is patented by Alexander W . Cadman. ( U. S. patent 464147, December 1, 1891.)

ALUM!Ntni DIPORTED AND ENTERED l'OR CONSUliPTI.ON IN THE UNITED STATES

FROM 1870 TO 1891.

Year ending-

I II Qu&ntity.l Value.

Year ending-

I I Quantity. V&lue.

Pounds.

June 30, 1870.... .. ...... ... ................ ..

1!\tl ........ ....... ..................

1!ml........... ....

2.00

1H74...... ......... 683.00

1875...... ......... 434.00

J87G ... ........ .... 139.00

1877.......... ..... 131. 00

1878........ ..... .. 251 .00

1879.... ... ........ 284.44

1880..... ... .... 340.75

18Xl...... ......... 517.10

$ 98 341 2
2,125 1,355 1,412 1,551 2,978 3,423
4,042 6,071

111110 30, 1882.............. . 1833............ .. .
1884 .. ............ .
lSil<i .............. Dec. Ml, 188li.. ........ .....
1887 ............. .
1883............ .. 188\1.. .............
JSI!O.. ............. 1 9J ..............

Pm,d. 566.50 426.25 595.00 439.00 452.10
1 2GO.OO
1,34R. 53
998.00 2,051. 00 3,906.00

$6,459
5,079 8,416 4,736
5,369 12,119
14,086 4,840 7,(62
6,263

COAL.

'
247

CHAPTER XXXIV.

CONTENTS.
ON SAND MouNTAIN. ON LooKOUT MouNTAIN .

CO.\L.

Only a remnant of the Coal Measures exist in north western Georgia, constituting the plateaus of Lookout (with Pigeon) and Sand mountains. The total length of the former mountain, in Georgia, i:> about 35 miles, with an area of 160 square miles; and the area of Sand mountain in the State is 50 square miles. The outlying ridges of Rocky mountain and Little Sand mountain do not contain any . workable coal seams.

ON SAND OR RACCOON MOUNTAIN.

This table-land crosses the extreme corner of the State, contain-

ing several workable seams of coal. The total thickness of the

Coal Measures on this plateau, in Georgia, is 800 feet. A complete

section of the lower 500 feet is given on page 144 in order to illus-

trate the structure of the Coal Measures, and as it is here considered

from an economic point, it may be repeated. Feet
Irregularly bedded sandstone or conglomerate __ __ ___ . ___ _70,

CastleRockcoal __ _ _____ - - - --- - -- __ wanting

Shale _.

. --- _ _-. ----

_________40

Dade coal seam___ ____ __ __ _____ _ __ ____________ average 3

Sandstone and sandy shale, variable _ ,_ , __ ______ _12

Coal (Reese's red ash seam)---

___ __ ______ _,._ _ 4

Shale ____ . _ _

6

Sandstone, or conglomerate-upper half thin bedded, lower half thicker, with shaly seams__ __ . ____ _ .. _... ______ 20

Coal, variable ____

-- ---------------- 0.5-3

'-

248

ECONOMIC RESOURCES.

Feet Sandstones and shale ____ _________ ___ ____ ... ___ __ _. __ 10 Blue shales _ . ______ _______ __ __, ____________ ____ 10
Sandstones, thin bedded, and shales or sandy shale __ _~ __ _15 Coal, 8 to 15 inches ___ _ ______ __ _____ ____ _____ _ _ 1.25
Shales, middle layer:; heavy bedded _.. _ __. __ ___ _ . ___ 54 Coal, smut ________ __ ____ ___________ _

Shale _ _ -------- - ---------------- _______ __ 15
Coal, smut ____ __ -- __ ---. _ - --- -- --- - --------Shale ______ .. ______ ___ ___ ______ ___ ___ . ______ 4

Concretionary beds_ _ . _.. _ --- - - --- - ---- - ---- - -- 6

Shale. __ ______ _

15

Sandstones, thick bedded __. ___ . _ _ ___ ___

15

Shale ____.. ___ _ ________ ..___ ___ ___ __ _

10

Shale with some thin layers of sandstones_ _______ __. . 95

Shales, concealed . ______ __ ____ _ _ _____ ____ _ 90

Limestones_

_____ __ . . . _______ -----

The principal workings are at Cole City upon the Dade coal seam, and also upon Reese's red ash seam. The coal lies in a basin, with a trend about N. 30 E. In the mines, the beds usually dip less than two feet per hundred, although at one locality, the seam rose 70 feet at an angle of 45 (Capt. Evans). The average thickness of the Dade seam is 3.5 feet, and it is moderately uniform over coniliderable areas. However, in places the coal seam pinches out, whilst in others the thickness is 9 feet, and at one place it is 17.5 feet. The Sand mountain coal has been extensively worked since 1873, but it was worked a quarter of a century earlier by Mr. Cooper and by Messrs. Gordon & Russell. The earlier workings were upon Castle Rock seam about 5 miles westward of Cole City. There the seam varied from 3 to 4 feet, but it is wanting near Cole City.
_Section at Castle Rock downward from the brow of the mountain::

COAL.

249

Feet

Conglomerate, capping table-land __ . . . ___ ------

35

Coal ____ __ - -

- - - -- --- - -- ---- -- -- -- ____0.5-3.4

Shale _ _ ------- -- - --- -.------ -- -- - - ------ _ 75 Coal (red ash yein) _ --- -- -- -- -- -------- - ------ ____ 1.5

Shale, exposed __ ---- - --- - -- - -------- - -- - -- _ ___ "- -- 100

At one locality the Castle Rock and Dade seams unite, owing to the absence of intervening shales. The Castle Rock seam in the original locality, is now exhausted as a source of coal. Another seam, called Reese's red ash seam, occurs a few feet below the Dade seam, and reaches a thickness of 4 feet.
The conglomerate of Sand mountain is mostly represented by massive sandstones of variable thickness. The upper conglomerate overlies the Castle Rock seam, which in position, is perhaps the most widespread bed of Coal Measures in Georgia. A comparison with the Lookout coal will be given under the latter locality.
The three seams of the Dade Coal Company, which have been worked on Sand mountain, occur between the lower and Iipper conglomerate. Beneath the lower conglomerate, which is thinner than on Lookout mountain, one workable seam occurs and possibly two; besides which there are still two other seams that may be seen.
The highest of these seams, below the lower conglomerate appears to be the Etna bed of Sand mountain, situated on an insular plateau between the Georgia line and the Tennessee river. The sections at Etna* and Cole City below the lower conglomerate, have about equal thickness, and each contains four known seams. The lowest of these at Etna are from 0.5 to 3 feet, whilst at Cole City, these two are represented by a few inches, which produce a zone of smutty shale along the exposed section.
North of Cole City the table-land rises about 300 feet above the upper conglomerate. Near the Tennessee liue, a mile from Mr. Liedermann's house, the ridge is capped by about 20 feet of sapd-

-:;'Geology of T en nessee, by Jas. M. S'afford, p. 383.

250

ECONO:mc RESOURCES.

stone, beneath which only shale was seen in the few exposures. But at 75 feet below the surface a bed of coal, from 2 to 3 feet thick, occurs. Othet beds may be found, but they were not exposed. Near the Etna line, just mentioned, Prof. Safford records the occurtence of three beds of coal from 2 to 6 feet thick-the middle having the greatest thickness, but containing interbedded layers of slate. This is notable when compared with the deposits on Lookout mountain.
The upper plateau ridge of Sand mountain is limited to a small area, owing to extensive denudations, leaving the upper conglomerate of Castle Rock region most commonly forming the margin of the table-land of Sand mountain; but even this conglomerate is wanting in places tipon the eastern side of the mountain. The surface of the plateau is often deeply indented by thP valleys, formed during the long continued action of evanescent streams. Thus, the sudace of the table-land is left more or less rugged.
Upon the eastern side of Sand mountain, several borings haYe been made by the New England Company; the records of which were furnished me by Mr. E. C. Stevens.

SECTION 1.

Feet

Surface earth____ __ ------ ------- - - . ----- ___ . 18

Sandstone - - ------ ____ ___

. _ _ ___ __46.5

Castle Rock coaL _____ _ __ . ____ _ ------- ___ ____ .wanting

Shale - - --__ Dade coal . _ _ _ . _ _____

_ - ------ - . . 28 ] 25

Conglomerate or sandstone . ____ .. _

Coal______ ___

_____ _

Sandstone Shale _ __ _ ___

Sandstone _ ____ _ __ . C6al __ . __ _ ____ .:. _.
Shale ____ _... . _

_4 3 . 2i)
- -- -- J. 2 J. [j
G .5
21.5 0.75 16.75

COAIJ.

2'51

Feet

Coal _

0.33

Sandstone ______ ____________ ------------. ---------- 5.66

Shale ___ ____ _ __ -- ---

--- . _ ------- ---106

The above section is on lot 91, tenth district.

SECTION 2.

Feet

Surface --- ---- _ __ __ ___

-- - -- ____ _ ___ 3

Sandstone_ _ __ __ ________ __

_ --- ----- _ 7

Conglomerate _____ ________ , _________ ---------- . Al

Castle Rock coaL ___ ____ . ___ . _ . - . --. - -. _--- .. - . . _ . _____ 0.75 Sandstone -----~- _____________ ._________ ___ . __ --- _____ 4.25 Slate __ ____ . ____ . _ __ _ _ __ ______ __ . . . __ ... . _. __ . __ .. __ 20 Dade coal _________ __ _________ __ :___ __ ___ _. __ ______ ___ __ 3

SECTION 3.

Feet

Surface

3

Conglomerate _____

- - ---- -- - -- - __ _ ___ .. ___50.75

Castle Rock coaL. __ .. _____ . _. __________ _ __ _ ____ ___ ___ 0.25

Shale _____ __ __ _ ------ ---- - ------- - ---- 8

Dade coal. _____ ___ __ ___ __ _ ____ __ __ __ __

4

SECTION 4.

Feet

Surface ____ _. . . .. . __ .. ____ __ .

3

Sandstone . _____ ... __

-- - ---- __51

Conglomerate. ---- - -- __ -------- -- _ - -- - . 12

Castle Rock coal ___ . --- --- _ ___ .... - --- --------- 0.25

Conglomerate. ____ .. ____________ .. _ ____ .. _______ . __ 6.25

Shale __ ~ ____________________ . __________ . ____ .. _______ 2.5

Dade coaL ___ ___ ___ ---- - -- --- _ ------- -- - 0.5 Slate __ - -------- .- __ ---~----- ------ __ _____ ___ 30,

252

ECONOMIC RESOURCES.

SECTION 5.

Feet

Surface

1.5

Sandstone _____ . _ . - .. ___________________ . ____ ____ ______ 8.5

Conglomerate _____ ---------- ___ _____ __ --_. __ _______ . 25.5

Castle RockcoaL -- ---- - -- -- ------ - -----

_ 0.25

Conglomerate ___________ . _____________ :._ ____________ 8.75

Shale : _... ___________________ . __________________________ 28

Dade coaL ______ . ____________ . _. ____________ . ______ . _ i

SECTION 6.
Feet Surface . ______ . ____ . ___ . _________________ .. ___ _ _ _ _ ____ 3 Conglomerate_ ___ ___ ____________________ _- . _.. .________ 22
Castle Rock coaL______________ _ _ _ ________ ____ __ ____ 0.25
Sandstone _____________________ ----------------------- 4.75
Shale -- -- - - -------- _ ____ _ -------------- ----- .15 Sandstone._____ _ _ ... ______ _______________________ 70.15 Conglomerate _____ . __ __ ____ ____ - _____ ____ __. __ .. 50.5

Shale __ - ---- -- -- _ ----- - - - -------- - --- - - -- -- 3 Conglomerate --- -- - ______ __ , _________________________ 12

Shale ____ --------------------------- --------- -- ---- - -- 2 Coal _____ ____ _______ -- _______________________ _ __ --. 3.5
Shale ---- .. ___ _____________________ __________ ________ 10.3

Surface _ . __ ___ ___

SECTION 7.
__. __ _ __ __ . _ . .

Feet 5

Shale_------------------------------------------ 7 Coal ____ ____ _ ____________________. __ ______ ______ ___ 1 Shale ______________ ____ _______________________ _ __ __ 9

Sandstone ----- --- __ __ ----- - --- ------- --- ___ ___ 103 Shale - - -- ------- - - ------ ---- ----- _________ _ 6 Sandstone __ _ ___ - - --- - ----------------- ---- - - --- 4 Shale ___ ' ._.____ ___________________________________ .. 129

Limestone..__ _ ___ . _________ ---- - --- . -------- - --- --- -..

COAL.

253

From these sections a con;;iclerable variation of the different strata are seen. At one place, the conglomerate is wanting owing to surface erosion, whilst at another it has been preserved to a thickness of 90 feet. Although the coal seams vary in thickness, they have a wide distribution, and vary in thickness from 0 to 7 feet. So also the strata intervening between the coal seams are constantly changing thickness, yet the general chatacteristics of the formation are constant. Whilst the Coal Measures occupy a long, synclinal trough, yet the individual beds are separated into basins of various extent, and represent the ineli vidual marshes of the Carboniferous period, when the region was occupied by extensive swamps more or less separated by such humnwcks as rise in the extensive swamps of Florida to-day. These changes in surface features gave rise to the thinning and thickening of the coal beds. Yet many of the deposits, although separated,. had donbtless a synchronous origin.
whether represented by a thinner or thicker seam of coal; the Castle Hock bed has a remarkably wide distribution ; so also has the Dade seam. The Reese's red ash seam may, in places, be mistaken for the Dade seam.
The whole surface of Sand mountain is underlaid by coal beds,, but the surface erosion has deeply incised the mouutain and produced many valleys, whereby the beds of coal have been extensively wasted. In fact, the extravagant waste of nature has been something enormous, destroying coal beds in Georgia far more extensive than those remaining.
The coal seams are rarely exposed at the surface, as the outcropping beds are decayed and covered or obliterated by the residual earths forming the superficial soils. Even when the streams have cut through the formations, the coal beds are often indicated only by blackened or smutty shales; the thickness of which is often reduced to less than that of the coal. Consequently, after the locations of the beds have been made, the coal must be exploited

264

ECONOMIC RESOl'RCEH.

in order to tell its value. In some cases the coal seams are so intermingled with coal shal1" as to impair their value.
LOOKOUT MOUNTAIN.
Lookout mountain consists of a plateau encircled by a wall of the uppei' conglomerate, corresponding to that of Sand mountain . . Above this trench, upon the central part of the mountain, portions of a higher plateau re inain, having a thickness above the conglomerate, reaching 750 feet. In the upper conglomerate, near Lulu lake, at Lookout point, beneath High point and elsewhere, a thin seam of coal is observed. Above this horizon there are at least fhe beds of coal. The best section of the upper Coal Measures may be seen along the Chickamanga and Round Mountain Railway, noticed in the scientific description of the mountain, and repeated here. It may be noted that all of these coal seams, in the following section, are in. a horizon above the upper conglomerate, and therefore, above the Castle Rock seam. The coal in the vicinity of Cole City, is geologically lower, but at the same time at a higher horizon than the Etna coal fields of Sand mountain in Tennessee.

SECTION ALONG ROUND MOUNTAIN AND CHICKAMAUGA RAILWAY.

Feet

Laminated shale"! with a few layers of sandstone on

Round moul).tain (partly concealed) __ __ _ __

200

Shales? (concealed) -- . _____________ _

65

Shale__

______ - ------------

9

(b) Coal and shale intimately interlaminated

14

Shale and sandy shale, 1;artly concealed

25

(c) Coal __ ---

0.7

Shale __

18

Sandstone, gray laminated ______ __ ____ -- .

:35

(d) Coal (3.5 to 4.5) dips 1 E. S. E.; altitnde at mouth of Durham Seam Mine, 1,849 feet above tide.

There is a slaty parting in the middle of the seam.

This bed is probably represented on the southwestern

side of the mountain at an altitude 30 feet lower..- 4

COAL.

255

Feet

Sandstone, irregularly and often thinly bedded and

undulating ___ ____ ______ __. _____ ___ __ ___ . _

80

Red shale ____ __ _ _ ___ __ __

11

Black shale ___ ____ __ _

4

Shale and sandy shale with a seam of limestone ___ _ 10

Blue shale above and variegated shale below. _ _

7

(e) Coal(altitude 1,668feet)----- _______ __________ _ 1.8:3

Thin, laminated, blue shales _ _ ___ . _ _ _ _ _ . 70

Red shales. __

. - ---- __ _

35

(f) Coal ___ _ ___ __ __ __ ___

. _. ___________ ~ _ 0.2

Light blue clay

___ __ _

2

Shales and sandy shales, passing into sandstones and

undulating so as to appear and disappear for a dis-

tance of three miles, but characterized by some

recognizable layers, estimated at ____ __ ________ _ 150

(g) Coal _____ _ _ __ .. - _________ . . ___ _ _______ _

1.66

Sandy shales, in steep nndnlatious __ . ______ --- 1 to 3

Heavy bedded sandstones __ ____ __

(h) CoaL _ _ ____

____ ___

25 ________ 0.20to0.83

Upper conglomemte and sandstone (this is at Eagle

cliff)

--- - -- ... --

150

Shales laminated and also tbicl{ bedded ------- - 120

Lower conglomerate and sandstone __ __________ __ 40

Shales, more or less concealed

_ . ___ _ 250 (?)

Round mountain rises above Lookout table-land as a prominent eminence, and upon its western side there is a be~ of coal 27

inches thick, and another double bed with each layer about 2 feet

thick, but separated by about 4 feet of shale. These beds are

above seam b (or that now being worked). The double seam may

be the equivalent of c. upon the eastern side of Round mountain.

There is probably another seam upon the western side of the

emmence.

256

ECONO~IIC RESOURCES .

The dip at the min es is less than one degree; so also the dip of the beds ou the western side of the upper ridge is low, although at one locality it amounted to 12. On the eastern side of Lookout plateau the strata dip northwestward, increasing to 12 or more, bringing the upper conglomerates to the great elevation of High point, but cutting off the eastward contin nation of the basin of the upper coal series, which lies in the central part of the mountain. The basin has, however, been very much eroded. In the vicinity of Eagle point, the rocks dip 20 N. 70 to 80 'V. Still farther northward the strata dip at much greater angles, but again flatten out towards Lookout point. So also they flatten out to the southward; consequently the beds, at least in the central part of the mountain, lie at low angles or gently undulate. It is only iu the central pOI'tion of the mountain that the Coal Measures remain. Several of the beds have a workable thickness.
Below the upper conglomerate there are at least two coal beds known at several points. The upper of these is closely relat~d to the conglomerate, being situated immediately below or within the sandstones. It is, probably, the representative of the Castle Rock coal on Sand mountain, and appears to be one of the mo~t widely distributed of the coal seams. It is of variable thickness and quality. Under High point the coal bed varies from one to three feet, and is shaly.
~outh of :Moore's gap the bed is still thicker. On the western side of Lookout plateau, overlooking Rising Fawn, a bed was opened of variable thickness, from 0 to 8 (?) feet. At Stephen's gap, on the south side of Johnson's crook, a coal seam has a thickness of fl'Om 1 to 3 feet. The position of the c0al at this point may be seen in the following section of the Coal Measure!":
Feet Conglomerate, on brow of mountain_ .. _____ . __ . __ _. _ 50 Shale __ ________ _ ------ - -- -- ---- __ ____ 30 Sandstone __ ___ ______ ___ __ ____ ______ _ __ 15
Coal -- -- ----- ---- -- - -- ---- - --- __ _..4-lOinches

COAL.

257

Feet

Fire clay_ . _ _________ - - -- - - - - - - - - - - - - - - - - - - -

7

Sandstone_________ ____ ______ Shale __. __ __ _ _ _

--- -- ------ - 10 ___ _ __ _ _110

This seam appears to belong to the lower of the two beds noted as occurring below the upper conglomerate. The rocks dip 18 S. 60 E. The same rocks and the upper coal seam occur in the ravine at the head of Trenton gulf, bnt it varies from 4 to 10 inche,;; in thickness.
Another seam of coal occurs about 30 feet below the conglom- erate, and is situated in the shale beds. As there are few diggings in the shale, the development of the coal is concealed by the disintegrated shales. In position this coal seems to be near that of the Dade coal beds. Above Rising Fawn furnace some extensive openings were formerly made, where the seam was from 3 to 5 feet thick, and said to vary from 0 to 8 feet in thickness, but there were no general workings. Owing to the covering of shale on the mountain side, the exploration of this bed can only be accomplished by borings or diggings, and may be founrl to have an extensive development in some localities.
At various points south of High point, upon the eastern side of Lookout mountain, the coal beds reoccur, and also on Pigeon mountain. Along the stream north of Neal's gap coal occurs immediately below the upper conglomerate. About a mile and a half north of Dougherty's gap, in a small ravine trending northward on the east side of Pigeon mountain, a foot of coal occurs beneath the heavy sandstone. This is along a synclinal axis.
'V4ilst there is somewhat of a general correlation between the coal beds of Sand and Lookout mountains, yet the variation in the thicknesses of different portions of the same basins, give rise to changing conditions.

(li)

258

ECOKmUC RESOURCES.

ANALYSES OF THE COAL.

Analysis of the Dade coal seam by Dr. Gustave Bidtel:

I. Fixed carbon _______________ 61.69 Volatile matter ____ __ ___ _____ 27.15 Ash __________ .__ __________ .10.59
Sulphur ____ ---- - - - - - -- -- __ 0;58 Phosphorus _ _____ .___ .. ____ _

II. (Old veius.) 74.8415.86 9.31 1.45 0.059

Analysis of the Reese Red Ash seam (next below Dade seam):

I. Fixed carbon ___ ---- __ __ _66.55
Volatile matter ._, __ ---- ____ 28.64 Ash ____ __ ______________ _ 4.41

II. (New veins.) 83.22
12.92 3.26

Sulphur ____ --- ~ ----- - -~ 1.04

1.05

Analysis of Dade coke :

Ash
26.12 22.91 24.74 16.73 21.73 20.15

Fixed Carbou.
64.98 71.79 68.15 76.58 69.66 70.48

Volntile Matter.
7.92 5.30 7.11 6.69 8.42 8.88

Phosphorus.
.061 .073

Sulphur.
.63 .28

Analysis of Round Mountain coal (seam d), by Dr. G. Bidtel, of Chattanooga : Fixed carbon _______ __ ________ __ __ __ ________ __ ___ .. 79.10 Volatile matter ___ ____ _________ ____ __ ____ _______ ____ .. 16.03 Ash ___ _________ ___ ____ ____ _____ ___________ _____ 4.81

Sulphur_ ___ -- - -- - - ----- --- - - --- ---- --- - - -- - - ___ 0.36 Phosphorus______ ___________ _.. . _____ _ . _________ ___ 0.007

100.307

COAL.

259

Another sample of this coal was analyzed by Mr. A. S. Hewitt, of New York: Fixed carbon ______ . ___ . _-- --- ________________ - -- . 75.956
Volatile matter ___ - - - --- ----- ------- - - ---- --- 21.011 :Moisture ____ -- - - ---.-- ------------ --- --- -- 0.615 Ash (salmon colored)-- - . - ---- - --- -- --- ______ __ 1.940 Sulphur ___________________ . ____ . _____________ ____ 0.478
Analysis of coke: Fixed carbon ______ ____ __ _ - -------------~-- ______ 90.31 Volatile matter.-~- _________ . _____ ___________ __ _ --- __ 1.20
Ash - ----------- ----- ------ ------ -- -- ----- - - --- - 8.53 Sulphur ________________________________ .. ______ ___ __ 0.53
The coke stands a high pressure.

ANALYSES OF RISING FAWN COAL.

Ash.
I. 2.93 II. . 3.92
III. 7.68

Fixed Carbon.
76.59 75.60 75.08

Volatile Matter.
20.01 19.89 17.24

Phosphorus

Sulphur.
1.09

.006 1.27

For comparison the two following analyses of favored types of northern coals is given :

Pocahontas.
Fixed carbon ..... . -- - -- --- - -- _ . 74.25 Volatile matter . _____ _ __ ___ --- ----- . 18.81 Water . _______ _ . . _ .. __ . __ . __ ______ 1.01
Ash __ ----- - - - - ---- - -- - ------ - - 5.19 Sulphur_ __ , . -- - -- . . __ _ - - - - ___ __ 0.73

Connellsville.
59.62 30.18
1.26 8.23 0.73

COAL MINES.
Dade Coal Mines have been largely worked for many years._ The great proportion of the coal is made into coke at the ovens situated below the mines ; it ie then shipped to Chattanooga and Rising Fawn for the production of pig iron. The mines are extensive,

260

ECONOUIC RESOURCES.

and some of the galleries, now honey-combing the mountain, are 3,000 feet long. Two seams are being worked upon at presentthe Dade and Red Ash. The output, from April 1, 1891, to Ap:r;il 2, 1892, was coal 9,888 tons, and coke 104,437 tons, or a total output of coal amounting to about 145,000 tons.
The Chickamauga Coal Company, operating Round mountain coal mines, commenced shipment August, 1892, and their operations indicate an output of 50,000 tons for the fit-st year.
The Dillon Land Company, Mrs. Howard, President, owns a considerable portion of Round monntain, but no mines have been operated i1pon thie property, which is the second largest upon Lookout mountain.
Besides the Dade Coal Company, the New England Company own extensive coal lands on Sand mountain, but have not worked any of their beds. Smaller interests are scattered over both Sand and Lookout mountain.

261

CHAPTER XXXV.

LIUESTONES, LIME ROCKS, CEMENT ROCKS.

CONTENTS.
LIMESTONES. DoLOMITE. DISTRIBUTION OF LIMESTONES IN GEOLOGICAL FORMATIONS. 00STANAULA LIMESTONE AND ANALYSESj CEMEN'l' ROCK. KNOX DOLO~UTE AND ANALYSES. CHICKAMAUGA LIMESTONE AND AXALYSES.

CHARACTER AND COMPOSITION OF LIMESTONES.

Limestone is used for constmction and road-making purposes,

and for lime and cement manufacture. It is largely nsed as a flux in blast furnaces, etc.
The calcareous matter is also a necessity in productive soils, and if not present in them it must be added. Hence, the applications

are extensive and variable. Pttre limestone is the carbouate of lime and contains lime 56,

aud carbonic acid 44 per cent. It is easily scratched with a knife, as the haruness is 3 ; specific gravity 2.50-2.80. It dissolves with effervescence in dilute acids.
Carbon dioxide or carbonic acid gas in water, clissol ves the mineral or rock, to be only again deposited npon escape of the gas from tpe water. Upon ignition the rock gives off carbon dioxide

and leaves lime.

The rock is rarely pure, but often approaches it with a semi-

crystalline texture, and usually light gray color, but it may be of any

color, owing to impurities.

t

The limestone often contains a small proportion of carbonate

of magnesia, in which case its general properties are not materially

262

ECONOl\IIC RESOURCES.

affected. It is sometimes rendered harder by included silica. The most common impurity is siliceous clay. Indeed, the clayey materials are sometimes present, to. even such proportions as to cause the rock to be considered a calcareous clay or shale. Sometimes the limestone and clay are naturally commingled, or again the clay, as an impurity, may occur in layers. For most purposes, the presence of clay in limestone impairs its value. Iron oxides are ofteu present in the rock, not only enough to give it coloring matter, but in proportion sufficient to affect its character. Organic matter may amount to even several per cent. In small quantities, phosphoric acid is commonly present in the limestone, and this adds to its value for agricultural purpose.
Dolomite or J.lfagnesian Limestone is a compound of the carbonate of lime and magnesia, and typically contains carbonate of lime 54.35, and carbonate of magnesia 45.65 per cent. But with this double compound, one or the other carbonate may be in excess. It is a little harder than limestone, bring 3.5-4 degrees, and also a little heavier, with gravity 2.8-3.0.
Unless powdered, it does not readily dissolve with effervescence in cold dilute acid.
The general characteristics are similar to those of common limestone, and indeed, it is not always popularly distinguished from the latter, as it undergoes the same variations.
Hydrnttl-ic o1 cement rocl~ is a limestone or dolomite containing free silica, clay and oxide of iron in such proportions that when burnt the compounds will combine and resist the action of water.

DISTRIBUTION OF THE LniESTONE IN GEOLOGICAL FORl>IA'l'ION8.
OOSTANAULA LIMESTONE AND ANALYSES.
In the belt of country surveyed there are limestones occurring in the Oostanaula shales in the country west of the Oostanaula fault. These are more or less siliceous and clayey limestones, but of variable texture. Upon the western side of and not distant

LUIESTONES.

263

from the Oostananla fault (see map), the limestone occurs in layers up to three feet in thickness, and are more or less veined with white calcite (pure limestone). As a type of this rock, partial analysis has been made from a sample, about three miles southwest of Rome. The pure veinous calcite war; rejected in the sample analyzed by Mr. J. M. McCandless, which gives a type of the massive rock:
Calcium carbonate __ __ __--- - -- - - --- - -- --- - - --- 74.38 Magnesium carbonate - - --- -- _ -- -- ----- - - - - --- . 8.79 Alumina _____ - ---- - --------------- -- - -- ------ 3.50 Ferric oxide __________________________ --- - -------- _ 2.05 Silica _____________ ___ _ - - - -- -- -- ------ - ------ 10.95
The coloring matter is organic, and consequently in burning, a light lime is produced.
Southwest of Rome bluffs of this rock rise 30 or 40 feet above the river. Else,vhere it forms extensive surface exposures.
Throughout the enormous development of the Cambrian shales, east of the Oostanaula fault, there are various beds of more or less impure bedded limestones belonging to the shale series. In color they range from dark brown or almost black to light gray; but they are usually dark colored. These deposits vary from 20 to 100 feet in thickness. Near Cunningham station a boring has been made 90 feet into the rock without penetrating it. It is sought for as a black marble, which is quite beautiful, taking a bright polish, but contains earthy matter, and is not highly crystalline.
If reference be made to this formation on the map, the occurrence of the limestone may be expected at points not distinct from the margins of the various belts of the shales, and in the valleys.
It is also exposed in nearly every stream flowing over the formation.
Some of these beds form fairly good building stones, others are

264

ECONOMIC RESOURCES.

rich in clay or iron, but they have all withstood the action of the weather. Sometimes these rocks form low bluffs.
The limestone is found at numerous places in the narrow belt near the East Tennessee, Virginia and Georgia Railway, from CaYe Spring entirely across Floyd county.
In the northeast portion of Bartow county, the limestone is shown along most of the streams, and also ou the sides of some of the ridges. From near Kingston to east of Adairsville there is a belt of about 45 feet of t.his limestone forming a ridge (a section is friven in the geological descri()tion of the formation, page 100). The rock varies in character; some of the beds produce a light-colored cement, which is extensively manufactured by Major George "raring, at Cement. TJ1e composition of this rock is seen in the analysis by the late Mr. vVilliam J. Land. The best bed for hydraulic purposes is a fine grained compact earthy rock, about seven feet thick:

I.

Calcium carbonate . ---------- _ ----- _43.50 Magnesium carbonate _ . _ __. _ _ . ______ . _ 26.00 Silica ____ ___________ ------ - ______ 22.10 Alumina ____ _______ _______ --- ____ _ . __ _____ 5.45

Ferrous oxide .. ---- -- --- - -- -------- -- --- 1.80

Organic matter ________ __ _ . __ -- __ _ ____ _ 0.15

Watet .. ____

_ ____ ________ 1.00

II. 55.00 26.10 10.00
6.10 2.00 0.50 0.30

Only a very few beds produce hydraulic cement. The cement bed contains much more magnesia than this limestone formation generally does. Its hydrauli c properties are derived from the silica uniting with the lime, magnesia, alumina and iron to form a cement.
Some of the beds of the limestone could be used for construction pmposes. Non-hydraulic lime was formerly made from some of the layers.
The lime works on this belt were started in 1845 by Mr. Charles A. Howard. In 1851' the manufacture of cement was commenced, and is now largely operated under Major G. H. Waring. The ridge is shown on plate X. (opposite), where also two of the kilns are shown.

PLATE XT. LD!ESTONE BLUFF OF TilE OOSTEi'\AULA SHALES AND KILI\S AT CEMENT.

LIMESTONES.

~65

The value of cement-making rock depends upon the above named constituents, which may be regarded as impurities in ordinary limestones, being in such proportions, that when the rock is burnt they will combine and set into impervious cement. There is no reason why at many other points on the liml:'stone beds of the Cambrian shales, cement-making rock may not be found, as well as that where it is already operated.
Indeed, some of the earthy beds of the succeeding Knox dolomite series may be found valuable for hydrauli~ purposes.
In the valleys of the various narrow belts of the Oostauaula series, west of Hocky Face and Taylor's Hidge, similar limestones also occur.

LIMESTONES OF THE KNOX DOLOMITE SERIES AND ANALYSES.

Most of the calcareous beds of this series are magnesian

limestones or dolomites. The structure of the formation is de-

scribed in the first part of the report'; only from the economic

standpoint are these rocks considered in this chapter. whilst some

limestones are in thick layers, others do not show well defined and

uniform bedding (see plate IT.), consequently the compact rocks

have often a thickness of many feet. Some of the belts are earthy

in texture, others are semi-crystalline. They are commonly more

or less siliceous. In color the rock varies from dark to light gray,

so that in any quarry a variety of shades is obtainable.

The dark coloring matter is partly organic, so that the lime made

from the rocks is of a light shade. Tlie more crystalline beds are

capable of Y.ielding good building stone and good magnesian lime.

The character of the more crystalline but dark dolomite may be

inferred from Mr. McCandless' analysis of the rock at Cave Spring:

Calcium carbonate __ _ . _.. ________________ ____ ____________ 53.44

Magnesium carbonate _______ ____ .. ______________ . ______ ..41.15

Alumina and ferric oxide _____ ____ _____ , -------

1.50

Silica . _ ____ ___ _______ __ _ _ ____ ______ . _______ 3. 75

The coloring matter is partly organic.

266

ECONOUIC RESOURCES.

Along the western border of the Knox series, there are heavy

beds of dolomitic limestone exposed on ridges for a thickness of 200

to 300 feet. It is mostly a magnesian limestone and often of clark

color. Its composition is variable, sometimes sufficiently pure for

furnace uses, or again containing much clayey matter. This is the

same rock formation which occurs east of Cunningham station, and

near Hermitage, in Floyd county. East of Cunningham quarries

have been opened, as also on another ridge a short distance to the

northeast belonging to Mr. Gibbons. At these places the

rock is dark brown and mottled with calcite veins. The coloring

is from organic matter, and consequently the lime is of light color.

It makes a very handsome ornamental stone when polished. As it

is somewhat earthy, it is most suitable for inside work, where the

polished surface is not exposed to the weather. The following

sample is from the "Egyptian Quarry," on the farm of Mr. Gib-

bons:

The 0omposition of this rock is seen from the analysis by Mr.

J. M. McCandless.

Calcium carbonate _______________ _- ---- -- - ------ __ 52.05

Magnesian carbonate __ __ ______ ___ ---- ------ -. Alumina __ _______ ____ - - -------- __ ___ - ___

36.32 2.68

Ferricoxide _______ ___ --- --- - -- -------- ____ :...1

Silica ___ -.___ _ __ _ ___

___ _____ _____ __ 6.47

The rocks of this horizon have been used for flux at the Ridge Valley furnace, near Herniitage.
All the other rocks of the Knox series to the eastward have different physical appearances and characteristics.
Of the fine grained, light gray dolomite of Dyke's creek, Mr. McCandless obtained the following composition :
Calciumcarbonate _____ -------------- -- ---- ___ __ ____ 52.64 Magnesian carbonate ____ __ _ __ ____ ___ -- _____ ______ 39.44

Alumina and ferric oxide ---- ---- - ---- -------- --- 1.76 Silica__________ ___ _____ -------- ---- -------- __ _ 6.25

LIMESTONES.

267

Three or four miles east of Adairsville, various dolomitic limestones occur on the ridges. Some of these are suitable for building purposes. At only a few points in Gordon county do these rocks occur exposed upon the ridges.
Just west of Spring Place, in Murray county, and at other points northward these rocks occur in high bluffs. Some of the dark varieties constitute a kind of black marble susceptible of high polish. It is, however, a more or less impure limestone. Again the same rocks form a bluff at Cedar Ridge in Whitfield county.
On many of the ridges of the Knox series, the limestone may be discovered at or near by the summit or npon one of their sides, and also adjacent to the valleys. Still mure earthy ridges are found than on the ridges just described.
Exposures are made at several places along the Rome Railway; at the Kingston lime quarry (in operation); at old kiln southwest of Kingston ; at Hardin's Cave, and on many ridges north of the Etowah river. In some cases, these are covered with cherty mantles, but streams often expose the beds of magnesian lime rock at a depth of a few feet.
On Ladd's mountain (see plate IV., page 44) three miles southwest of Cartersville, is one of the most extensive quarries opened, \vhich supplies three large lime kilns. Here, an exposure of more or less imperfectly bedded, compact limestones, of various textures, is seen to a height of 150 feet. The analysis of the lime was made by Mr. Pratt for the company:
Lime ___________ _- -.-- - -- - _____ _- _-- - -------- 34.070 J\'Iagnesia __ _ - -- -- - -- -- - -- _________ -- -- ____ 55.736 Alumina and ferric oxide ___ ___ . _ . _____ __ _. ______ _ 1.236 Silica_ ______________ .___ __ __________________ ~ __ . 7.252 Moisture __ ___.____ ___ _ __ __ __ __ . . ____ ______ _ 1.622
Occasional layers contain flinty matter which has to be rejected. Some of the layers are suitable for building materials.
At various locations, situated on the ridges ofthe Knox series

268

ECONOMIC RESOURCES.

in Catoosa, vValker and other northwestern counties, the dolomite rises in cliffs as near the end of John's, and near the Tennessee line at Grayville, where high bluffs have been cut into by quarrying for lime (see local geology), as there are extensive kilns situated there.

LIMESTONES OF THE CHICKAMAUGA SERIES AND ANALYSESo

These rocks are mostly pure limestone, non-magnesian. They

occur adjacent to the branches of the Cedar creek, from Cedartown

southoward, along Fish, Camp and Euharlee creeks.

On a number of ridges, in the Rockmart district, the limestones

rise up to form bold bluffs, but except in this region, they do not

form high ridges. The rock is often in compact, thick beds.

Many portions are of light gray color. The texture is compact

and semi-crystalline, as the limestone is semi-metamorphic. Some

of the beds are suitable for building stones. For lime or for fur-

naces, their quality may be inferred ftom tbe analysis.

Sample from Cedartown, iwalyzed by the late Mr. W. J. Land:

Calciumcarbonate ________________ . -- - - _ - -- - 94.37 Magnesian carbonate ___ ' __ __ __ ______ . . ___ __ ... _ _____ 2.10 Alumina __... __ __ ___ - -------- _ _______ ____ 2.23

Undetermined . ---- --- ____ .

____ ______ __ 0 1.30

100.00

Sample from Devitte lime quarry, on side of a bold ridge, ana-

lyzed for the Cherokee Iron Company. This limestone is exten-

sively used in fluxing and fot lime:

Calcium carbonate . _________ ------- __ __ -- - - 95.203

Magnesian carbonate

_ _____ -- ---------

Alumina

and ferric

oxide _____ .

__

0 _

_

_

_

_ _

_

_



_

_

___



Insoluble .. _____ . _____ _____ . ____

_________ _

2.171 0.400 2.300

100.074 Various other ridges are favorably situated for the extraction of limestone, but they do not occur outside of the district given.

LUfES'fONES.

26 9

This rock afforrls our best non-magnesian lime. The limestones exposed in the valleys at the edges of the Rockmart series, in the narrow basin of.Murray and Whitfield counties, are of similar character to those in Polk county, although less extensively developed, but they are available for local uses. In the belts of the Chickamauga series in Walker, Dade and other counties the limestones are sometimes in thick, compact beds, but more frequently the laminations are more developed than in the Polk district, as also their earthy character. Still there is considerable variation, from quite pure limestone to others very impure as may be seen south of Trenton. In the valley of Lookout creek there is a fine grained, .compact, light-colored limestone, which yielded Mr. McCandless the following analysis:
Calcium carbonate________ -- ___ . __ __--- -- __ __ _-- -- _ 55.47
Magnesiancarbonate ______ - ----- - ---- --- ---- --- 25.33 Alumina and ferric oxide (mostly alumina) - -- - .. _ __ _ 9.50 Siliceous residue ___ ___________________ ------ ----- - 8.16

98.46 This rock has the appearance of lithographic stone, but breaks with a conchoidal fracture. Near by (south of Trenton) another light-colored, but crystalliue rock, is of much greater purity.
Calcium carbonate _____ __ ___ __________. _ _------ ______ 91.40 Magnesian carbonate _______ ___ _ _______ -- - .. ----- - 3.75 Alumina and ferric oxide __ ____ ____ __ ____ _.:_ ____ ____ ].80 Siliceous residue ___________ ____ _ ___ _ - --- - - -- - -- -- - 2.82

99.77
The limestones of the Chickamauga series furnish abundance of road material, and by selection good lime and building material, which last is often in layers of convenient thickness.

~70

ECONOJ\IIC RESOURCES.

DEATON LH'I:ESTONES.
As a building material, this series does not furnish a source for limestone. But some of the ferruginous beds, as at the Deaton mines, contains 30 per cent. of iron and are self-fluxing and may yet be used in that connection.

RED MO'C'NTAIN LUiESTONE.
Amongst the shales of this series only occasional thin layers of limestones are seen above the drainage leyel. But in mines below the drainage beds level, a foot or more in thickness occur. They are commonly earthy and siliceous and usually somewhat ferruginous. Except in connection with .mining iron ore, they are of no economic value.

FORT PAYNE LIMESTONES.
These limestones are too much commingled with chert to form good building material, but they produce excellent road material. They usually occur at the edge of the Mountain Limestone, and on ridges succeeding the "fossil" ore beds.

FLOYD LUIESTONES.
west of Rome, and elsewhere, there are limited exposures of
heavy bedded limestones, occurring in this formation, forming good building material and also lime. But the exposures are not numerous.
MOUNTAIN LU!ESTONES.
This rock is of enormous development upon the sides of Sand, Lookout and Pigeon mountains, being most uncovered at the northern end of Pigeon mountain. It occurs in thick beds, and is available for building purposes of all kinds. The color is often attractive. The rock has usually a compact texture. It varies in degrees of purity. High up upon the eaotern side of Sand mountain, a variety with crystalline texture yielded Mr. McCandless the following analysis :

LIMESTONES.

271

CalCium carbonate . ___________ ------ -- .. ------- . ___ . 80.60 Magnesian carbonate __ ..: .. ---- --- .. ---- --- --- -- __ ___ _ 2.45 Aluminaandferric oxide .------------------------ 3.20 Siliceous residue __ ------- -- - --- -- ----- - ----- _____ 12.70

98.95
The upper beds are often the more earthy. Near the base of the series, at Rising Fawn, the rock yielded (J. M. McCandless): Calciumcarbonate ____________.________________ ______ 96.13 Magnesian carbonate _________ _____ ------- - --- ____ 2.05 Alumina and ferric oxide__ .. ________________________ 1.00 Siliceous residue _____ . _____ .. _- __ _ ____ . ___ . _ . _ . ____ _ 0.95

100.13
From these analyses it may he seen that there is a great range in the varieties of limestones, but such as yield excellent lime, good for furnace use and of qualities suitable for building purposes, with often a fine gray or bluish color.

272

ECONO.i\JIC RESOURCES.

CHAPTER XXXVI.
SANDSTO~ES.
CONTENTS.
OF 'HIC CHILHOWIE SERIES. OF THE OoSTANAULA SERIES. OF THE RED MOUNTAIN SERIES. OF THE Sun-CARBONIFEROus SERIES. OF THE COAL MEASURES.
OOSTANADI,A AND CHILHOWIE SERIES.
Quartzite or crystalline sandstone, of beautiful fine grained texture, is found on uncovered cliffs, in abundance, on Indian mountain, near Etna. Owing to its hardness, the cost of building material is high, but when needed, the quantity and availability of this durable material is unlimited.
At a few points in the ridges south of Rome, along the eastern side of the Oostanaula fault, Randstones occur, but the beds are rarely two feet thick, and are not generally exposed at the <surface in quantities sufficient for building purposes.
RED MOUNTAIN SERIES.
Massive and thinner bedded gray sandstones occur on Rocky Face, Chattoogata, Horn's, John's, White Oak, Taylor's and Lavender mountains, as also on Horseleg mountain, and near Loughridge (Murray county). At many localities the rock is sufficiently uncovered and in abundant quantities for building purposes. The texture varies from fine to coarse grained. Whilst the rock is available upon the surface of many portions of Taylor's ridge and White Oak mountains, yet on the mountain sides, and on the western ridges it is not so abundant as in the more eastern ridges. West of Taylor's ridge these sandstones are less important.

SANDSTONES.

273

Brown sandstone, making a beautiful building stone, is more or less associated with the gray sandstone in the ridges named, and some workings have been commenced on White Oak mountain, where blocks three feet thiek can be obtained. Amongst the shales in many places on the ridges above named beds of brown sandstone, from one to ten feet thick, can be quarried, as in Lavender mountains no1thwest of Rome; in Taylor's ridge, east of Summerville and of Lafayette, on Rocky Face and many other localities.
Flagstones or sandstones in thin beds are frequently interbedded amongst the shale:;. These are mmally from two to eight inches thick. They occur not only on Lavender, Taylor's and other eastern ridges, but are well developed in Shinbone ridge, and in the cuts of the Chattanooga Southern Railway across the end of Pigeon mountain and elsewhere. These flagstones are mostly of a reddish tint, sometimes brown, and occasionally gray. They are locally used for chimneys, and may be applied more extensively. Wherever the formation occurs, there are some uncovered flags, but they are often covered so as not to form surface features.
SUB-CARBONIFEROUS SERIES.
The rocks of the Fort Payne formation are limestones, but with siliceous deposits in :'lome place:'i, developed to such an extent as to cause them to be varieties of sand rocks wbich resist weathering proces::;es. They are, however, too concretionary and otherwise unfit or building purposes, but make good road material.
COAL MEASURES.
In this formation there is an abundance of beautiful gray sandstone suitable for any structural purposes. It is sometimes fine grained, but passes to coarse grain, or fine conglomerate when the scattered pebbles are half an inch in diameter. These sandstones occur in massive beds, and produce bold cliffs along the margins of Sand, Lookont, Pigeon, Rocky and Little Sand mountains.
(18)

274

ECONOMIC RESOURCES.

On other beds they vary in thickness of six to twelve inches, and have often a great degree of purity, but again other layers are somewhat earthy. The supply is inexhaustible, and at some points railroad facilities are already available, as along the Chickamauga & Lookout railway, upon the eastern side of Lookout mountain, where it passes the bold sandstone beds of Eagle Cliff.

SLATES.

275

CH:APTER XXXVII.
SLATES.
As a geological formation, the Rockmart slates are described in Part I. As an economic product, only the ridges form suitable locations for quarries. The slates in the ridges are hard, and are frequently very little aflected by weather, except the thin surface coating. At other times the surface slates are weathered to a depth of twenty feet. In many localities, the slates are consequently unavailable, or where available, they are found to be unsuitable for splitting. But in the ridge, at Rockmart, good, cleavable slates have been extensively quarried for many years. Whe~ viewing the vast heaps of waste material, unfavorable impressions might at first be formed; but the wastes in every slate quarry are equally large. These, however, might be somewhat reduced with more systematic methods of working. The available slate deposits at Rockmart belong to various individuals, and the quarrying could be more effectively carried on if the boundary lines were removed by a combination of interests. The three principal owners are: Col. T. F. Dever, the Seaborn Joms Estate and the Rockmart Land Improvement Company.
There are other slate ridges in this district, but none have so far been found as suitable for extraction and splitting, which is a most
a impoJ:tant consideration, for even the best quarries only yield rock
in which there are gre.at wastes. In several localities, as Etna, slates of the Oostanaula series oc-
cur. In some; places those may be valuable, but in other localities the metamorphism has not rendered the slates sufficiently durable.
,

276

ECONmiiC RESOUHCES.

CHAPTER XXXVIII.
CLAYS AND BRICK PAVE:VIENT8.
CONTENTS.
NoTE. liHICJC PAVI!MENTS A~D .KINDS Ot' CLAY REQUIRED. CLAYS OF Non'l'HWEB1'ERN GEORGIA AND ANALYSE~; Composition of Clay;
Kaolin Type; Residual Clays; Clays from Disintegrated Shales; Alluvial Clays.
NOTE.
The subjept of clays is one of the most important in connection with the survey. Not merely are the clays of interest in the manu facture of common brick for local purposes, but there are favored localities, where material suitable for fine qualities of pressed brick and terra cotta are obtainable, and from which shipments to other localities can be made. Another rising industry in the country is vitrified brick for roadways, and only certain clays are suitable for making this popular paving material. Modern improvements in the manufacture of roof tiling are leading to the return to the ancient fireproof and picturesque roofing. Other clays for coarse pottery, and kaolin for fine pottery, are in demand. No subject of economic geology is more important, and consequently thi,; chapter was delayed in its preparation until the last, in the hope that adequate time and means could be given for a satisfactory and elaborate chapter. This time and means have never been at. the anthor's disposal, and, accordingly, only a few noteR, without sufficient study, can be given; but these few notes are better than no report at all.

BRICK PAVEMEN'l'S.

277

BRICK PAVEMENT8 AND KINDS OF CLAY REQL'IRED.

USE OF BRICK.

Iu connection with roads, the question of brick pavements in

cities and towns is notable, on account of the rising importa1ice

of this material and the consequent demand for .suitable clays.

In Holland, and other countries of Europe, brick pavements

have long been in use, on account of the absence of stone. The

durability of vitrified bricks in Europe, has led to their introduc-

tion into America. In Charleston, W.Va., brick pavements were

first laid down eighteen years ago, and are still perfectly good and

smooth. Since their introduction in that city, bric.k pavements

have grown steadily in favor; and during the last four or five

years, so rapid bas been the revolution in street making, that bricks

are now used in 27 5 cities and towns.

'

The merits of different pavements have been thus compared:

"GRANITE BLOCKs-Merits: Durable, clean, healthy. Defects: Noisy, uncomfortable, slippery when worn, expensive first cost.

"STREET ASPHAL'l'UM-Merits: Comfortable, noiseless, healthful. Defects: Short-lived; expensive to repair; slippery on grades; expensive first cost.

"BRICKs-Merits: Comfortable, durable, clean, non-slippery, healthy, easy to repair. Defects: Moderate first cost when supply is local.

The cost of brick pavements varies from $1.05 per yard at Wheeling, W.Va., to $2.32 at Memphis, whilst the cost of granite ranges from $2.50 to over $4.50, according to location, except at Atlanta, where it is reduced to $1.50 per yard.
The bricks form a payement almost as smooth as asphaltum, nonslippery, clean, and being durable, are rapidly growing in popularity, to the exclusion of rough stones. Thus, the bricks not merely snppl)r paving materials in cities, where no stones are available, but

278

ECONOMIC! RESOURCES.

replace them in their natural market. As brick paving is a great future question for Georgia, a few notes are here given to call attention to it and to the required clays, which come into the field of this survey.
The bricks must be vitrified; that is, made out of clays, or admixtures of clays, which will slightly fuse, so that the components are more or less melted together throughout the mass. This requirement necessitates the burning of the clay in closed, downdraft kilns, and at higher temperature and for a longer period than ordinary bricks. The bricks, to be good Jl4tVers, must absorb little or no moisture; be hard, tough, dense, and stanJ a pressure of 6,000 pounds to the square inch. Such bricks have been used for four years at Burlington, Iowa, and show no perceptible wear.
The testimony of 275 cities and towns, in population ranging from Philadelphia, Detroit, Cincinnati and Wheeling to small towns, show the favor into which brick pavers are growing.
In many places, bricks of ordinary size are recommended, so that those rejected for paving purposes can be used for ordinary constructions. In other localities, larger blocks are used. In the former case, the product is somewhat more certain.

THE KINDS OF CLAY REQUIRED.

At Fort Smith, Arkansas, the vitrified bricks are made from a shale containing (Branner):

Silica ___ _ -- ~. Alumina___ _ _ . ___ ___ ___ _ __________ _____ _

58.43 22.50

Oxide of iron ____ ------. ___ ---- .. .. - ----- - _ __ 8.35 Magnesia ___________ . ____ __ __ __ ___ _.. ______ __ _ ____ _ 1.1-J

Potash -- -- - ---- - - - --------- - - ------- ______ _ :J..18

Soda _________ .. __ __ __ _ _. _ __ - - -- - --- - - --- - -- - - - -- 1.(:

Sulphur ______________ ___ _ _ _____ --- -- - -- - __ __ __- _ 1.16

Loss on ignition _ ___________ , __ --- - - --- . ------ 6.20

100.99

BRICK PAVEMENTS.

279

At Bucyrus, Ohio, an exceptionally fine quality of vitrified

bricks is made from shale containing:

Silica ___ ___ _ _ - - - - - - - --- -- -- - - --- ------ 66.66 Alumina. ________ . __ . __ _ _______ . __ -- __ - _____ ___ 19.20

Iron sesquioxide - ---- ___ -- -- _ - - - - __ - -- --- - - - - - 6.18

1.\<Iagnesia _____ _ - - - . -- - . - -- ------- -- - -- - - -- none.

Organic matter ___ ___ ... . ----- - - _ ------------. none.

Lime carbonate __ __

. - ----- __ __ . -- -- 0.72

"Free alumina" _____ . .. _____ ____ __ ________ . ______ _ 7.24

100.00 The color of the bricP.:s is immaterial. Mere fusion is not alone required, but this combined with toughness and hardness. In order to effect this fusion, the clays require iron, or this with small quantities of alkalies. Fire clays are by themselves valueless. On the other hand, clays containing lime in quantities, akalies, or an exces>J of iron, are unsuitable, as these give too great fusibility, so that the bricks will not stand the high temperature of the kilns, or become too brittle. Shales are often more desirable than clays, as they contain less grit, which causes the brick to wear more rapidly away. Again, good pavers are made from an admixture of fire clays or semi-fire clays, which will fuse the whole together; but the less mixed materials are those preferred. These notes on brick paving, are added as an accompaniment to good roads, which belong to the province of the engineer, but the question of clays belongs to geology.

CJ,AYS OF NORTHWESTERN GEORGIA AND ANALYSES.
COJ\IPOSITIONS OF CLAY.
Pure clay or kaolin contains : Silica _____ _ ___ ______ _ . ____ ______ ___ . . ____ - ------ Alumina ____ ______ ______ - - - _ . _.. __ __ _ _____ ___ Water _______________ __ _____ ____ ___ ____ _ -- - --- - --

46.3 39.8 13.9

100.00 It is primarily derived from the decay of feldspar or similar minerals. Comparatively little clay has the above simple composi-

280

ECONOll:liC RESOURCES.

tion. Generally a portion of the feldspar is only partially decomposed, and contains potash or soda. So, also, lime and magnesia may be present in traces. Iron, with smaller portions of manganese, is commonly present even in light colored clays, and in colored clays the quantity of iron is often large. In onr Georgia clays there is often a remarkably large per cent. of titanic acid. In addition to all of these constituents, which are present in onl.v small percentages, there is an admixture of ,free silica. Indeed, the clayey character of these superficial earths is maintained when the quantity of alumina is diminished to only~a few per cent., owing to the exeess of free silica. In nature, the silica often increases fio that the earths pass into clayey sands rather than sandy clays. In north western Georgia, there are several types of clay-(1) the kaolin-like clays, (2) the clays derived from the decay of limestones and calcareous shales, (0) tho3e formed from the disintegration of shales, and (4) alluvial deposits.
K \OLIN TYPE.
These clays occur ae "horses" (see figure 22, page 155) or in sheets or pockets in the residual earths, derived from the decay of the Knox dolomite and Fort Payne chert series. Sometimes they are pure white, with occasional stains of iron, or the stains may pervade the mass in the form of streaks. Again, the clay::; are of purple tint. They often occur in large bodieti. In the cherty remains of other portionf:i of the Knox dolomite, the silireoul' nodules are imbedded in white, siliceous, chalky clay, as near Cave Spring; or in Lookout valley, in Fort Payne chert. From this siliceous matter, the white clay could be mechanically separate<l, if the price would warrant the labor. Some of these clays are of fine quality, as at Woodlands. Halloysite,, as noted before, oceurs under similar conditions in the Fort Payne chert, and can be used for fine porcelain ware. Composition of the white clay is shown in the following analysis by Mr. McCaudless-the sample being taken from beauxite beds on Flowery Branch, Floyd county:

CLAYH.

281

~~\.lumina __ _ _ __ ------- - -_ - ----- _ ___ _ ___ . __ 38.60

Ferric oxide------ - _ _ ___ _...... - --- --- -----. __ -- 1.45

Potash __________ - ---- ---- - - . --- - ----- - 0.09

Soda ______ - ----- --- .- . - ------ ----------- - -- 0.02

.Lime ____ . .. _ - -- - - - -- -- -- --

-- ---- 0.00

~~agn_esia __ ___ __ --- -- - --- ___ - -- -- - - ---- - - 0.30

Tttamc acHL ____, _ - - _ --- - ,_ __ ----- _____ . __ 1.95

Silica ~combined) --- --- ------- ---- - - - -- ------ - - 40.40 Silica (free sand) . ___ _ ---- - ---- ___ ___ ___ _ _ ---- 0.80

Water (oowbined) __ _ ----- - - - --- ------ ----- - - - - - . 16.3-5

Water (h chu. o pic) ____ _____ -----. ___ . _

0.30

100.31

This is a kaolin of nearly theoretical composition, with small proportions of impurities. It contains only the smallest trace of undecomposed feldspar, and alkalies, and conseqnently would form an infusible clay with even the amount of iron prese~t. The iron is, however, not uniform in th e clay, but occurs in creviceFJ.
Such clays are of very common occurrence in association with beauxite beds, and with some iron ore beds. In the latter case, however, iron iFJ apt to be present in larger quantities. A type of th e clayFJ as seen in the "Horses" of the iron ore beds is gi yen in the following analysis (Mr. McCandless) of a sample from Grady.

Alumina ____ . _____ .... --- - - ____ __ ___ _

15.41

Ferric oxide_ . __ ,_- __ _-- - --- _ _____

6.0()

Potash _

- - --- --- __ _ ____ _ - ------ __ 4.55

Soda ____ ----- -------- - ----- - - -- ---- ----- 0.34

Lime __ --.--- ---- __ ____ ___ ______ - ----- ------ - 0.00

Magnesia __ ____ ___ , __ ___ __ __ ----- -- ----- ____ 1.29

Titanic acid ____ ___ __ . _______ ___

_ ___ _ - 1.35

Silica (combined) --- -- - - - - - - --- - - -_-- ------ - -___ 20.10 Silica(freesand).. -------------- - - ------- ----- 46.10 Water (combined).. --- -------- ----- ------ 4.75 Water (hydroscopic) .. __ _ ____ _ .. __ . _. _ __ ___ ___ ___ _ 0.20

100.15
.,.

282

}~CONO~IIC RESOURCE S.

In this clay, nearly half the mass is composed of free sand, and otherwise indicates a condition of rapid deposition, in that it contains much undecomposed feldspar, as shown from the large quantity of potash and soda present. The clay is colored purplewhite. It would he somewhat fusible, but it is worth the experiment for the manufacture of vitrified bricks. From other clay horses, I have seen clay which can be made into white stoneware, but only where the. iron is in much smaller quantities would the color be fit for the finer wares. Some of these deposits are suitable for fire clay purposes.
These clays would justify experimentations, which are necessary before their full value can be determined.
The clays of the above types occur in residual earths, yet they are not themselves residual of tbP. limestones, as they occur in distinct pockets or beds, in which condition they originally occurred amongst the limestones, out of which they have been disinterred by the decay and degradation of the calcareous matter. Their original source, however, was from the metamorphic rocks to the tJast, which were remarkably free from calcareous minerals, and not from the limestones, although occurring with them.
RESIDUAL CLAYS.
These clays are derived from the decay of earthy limestones and calcareous shales belonging to variOIJfl series of the Paleozoic group. There is a marked difference in the charactel' according to their eource or formations. These clays also form the soils, and are described in that part of the report. In some cases these clays produce fair common brick. However, many of them are too poor in alumina and too rich in fusible materials to make fine products. The clays derived from the shales are very siliceous, as also those from the cherty limestones, whilst those derived from the decay of the more calcareous rocks are much more aluminous; but at the same time they are commonly. very rich in iron. In some localities, however, fair brick can be made, when not burned

CLAYS.

283

at too high a temperature, which would tend to melt the product.

Thus. at Cartersville, a fair brick is made from residual clay of the

following composition (analyzed by Mr. Mc"Candless) :

Silica _______ -- __ -- -- ---- --- - -

58.63

Alumina ___________ ____ ----------- - ------- - - - ---- 20.47

Ferric oxide _______ - - - --------- - --- - ------ - ------ 8.58 Lin1e .. ________ -- - ----- - ---- -- ----- .. - ----- - -------- - - - Trace Magnesia _____ __ __.. _- - __ -- - - - - - - ...- - - - ... - - - - - ____ __ 1.42

Potash -- - ------------------~------------------- 3.86 Soda- ----- ----------------------- ___ _, ____ _ 0.14

Titanic acid (with alumina)---- . - -- - ----- - --------- -_ Water (hygroscopic) -------- ---- --------------- 0.20 Water(combined) _ - - -- --------- -- --- - --- -------- 7.06

100.36
The fusibility arises from the large amount of potash in addition to the iron, but it requires a higher temperature to melt the product than if the fu~ible material were mostly lime. The absence of the lime is commented on elsewhere. The red clays derived from the Knox dolomite often contain not only a fait amount of lime, but along with it so much iton that brick made from it would be of very poor quality.
CLAYS F ROM DI8IN'rEGRA1'ED SHALES.
These shales are of variable character, and whilst many of them retain a shingly appearance, yet in composition they are often similar to clays from which good bricks are made. Indeed, to-day some of the finest bricks are made hy the modern machinery from ground shale in preference to their manufacture from plastic clay. In this connection a few analyses have been made and are here
, given, without a detailed study.
An analysis is given of oa light colored hydromica shale on the ridge above the Etowah iron bridge south of Cartersville. It is on the border of the metamorphic zone from which many of the

284

EUOXmiiC RESOlTRCES.

clays originally came, whether to form the shales or to be incorporated in calcareous rocks. Their economic value justifies further investigation (Mr. McCandless analyst):

Silica (freesand) --------- --

_ ---- --- - 62 .30

Silica (combined) __ __ __ . . ___ . __ ____ _ ___ __

9 .3 0

Alumina ___ ------- -- --- ___ ----------

11.50

Ferric oxide .... _____ .. _.. _ __.. ___ ____ . _.. __ .. __ _

5.59

Manganese dioxide ____________ __ _ __ , ____ - -- _ 0.60

Lime .. _ __

-- - -- -- . - --- 00.0

Magnesia .... ---- ---------- --- _ ----- - - ____ _ 1.30

Potash _______ ---- - - -- --- -- - - - __ ----- - 4.20

Soda ________ . - ------- __ __

_ ___ .. ______ _ 0.35

Titanic acid_ .._ ___ _.. ____ __ __. .

1.10

Water (combined) _ ------- -

3.80

Water (hygroscopic)------- __ __

0.15

100.19

In the valley a mile southwest of Cartersville a light red shale, at first regarded as belonging to the Oostanaula senes, yielded to Mr. McCandless an analysis similar to the last:

Silica (sand) ..... .......... .. ________ --- ----- _____ _ 39.20

Silica (combined)-- ___ _ ______ __ ____ _.--. __ ____ _-- _ 19.40

Alumina:. __ ___ _ _____ __ ,. __ __ __ ____ ------ - -- --- - 18.05

Ferric oxide .. _ ___ __ _. ____ . .. ___ __

8.31

L im _

_ ----- --- ----

___ ----- - __ __ 0.00

Magnesia ____ __ ___ _____ ___

-- ----- - -- --- -- 1.55

Potash _____ ________ ___ ___ ------- - ____ -- ------- 4.63
Soda _.. ___ __ ________ .. ______ .. _______ .. _.. _ __ ___ ___ __.. 0.3a

Titanic acid _ ___ ___ --- - -- - --- ----------- ---- -- -- 0.68 VYatflL' (hygroscopic) .... . .. __ _____ ___ ---------- --- ~40

Water (combined) ____

---------- ------ 7.60

100.15

CLAYS.

285

Evidently these clays are of the same formation as on the moun- tain, and their economic value will require testing, but their composition is such as to be of interest.
The less calcareous of the Oostanaula shales about two miles northwest of Cartersville were analyzed and the composition was found by Mr. McCandless to be as follows:

Silica ___ ____________ - - - _ - - _---- - _- --- -- - . -- __ -- _- 52.82

Alumina __ ___ --- ___ -------------- ----- ----

26.17

Ferric oxide__ ___________ ___ _ - _--- __ .___ __ _ . _.. ____ _ 9.46

Lime ___ _ ___ - ----- --- ------------ ----------- trace Magnesia _ _ :_________ -- -- - . ___ - . - - ___ . ___________ . __ 1.08

Potash _______ - - _. ---- - -- -- - -- - - - - - - -- -- -- -- -- - - --- . _ 2.71 Soda __________ . - _ ________ -- .. ___ - ___ - _- _______ . _____ _ 0.20

Titanic acid with alumina ______ - ------------ -- - -- - __

Water (hygL'L npi c) --- - - - ---- -- -- -- ------ ----- - 0.23

Water ( cmbiu d) ----- - -- - --- --- - -- - ------- - - - ---- 7.00

99.67

As this analysis is closely that of vitrifying brick clay elsewhere, the practical test should be made.
Uaen stone (?) At Rockmart, certain of the slates upon the upper
portion of the ridges have decomposed; producing a buff colored hard slate or clay handed with a ligneous structure. It is cap::tble of being sawed or turned into ornaments.
The following analysis was made by Dr. Robert Peters of Kentucky (sample air dri<:d):

Silica ___ _ __ __ ____ --- -- ------------------ 61.66

Alumina_

19.64

Ferric oxide ______ . -------- - --------------- - --- 7.54 Soda ___________ . __ _______ ____ ____ ____ _ __ . ___ . ______ _ 1.05

Potash ___ . ____ . .... ___ .. __ - .... - __ - -. ___ -'- - - --- -- -- - . - . -- 1.27

Lime and magnesia __ -~ - ---- _____ ________ --- ----- -- trace

Moisture not estimated __ _ -- - --- -- -- --- ------- - --

91.Hi

286

ECONOMIC RE!:lOURCES.

Samples of the bricks made from this clay were amongst the most beautiful that I have seen, also the clay vitrified, producing apparently a good paving brick.
Clays making good common aud also vitrified bricks have been obtained in other States from the shales of the Coal Measure. Analyses of these in Georgia have not been made, nor of the shales of the Red Mountain series, both of which are well located - for railway facilities. An approach to the composition of the Red Mountain shale is seen in the analysis of the soil on a future page. That sample, however, is more ferruginous than the normal shales.
A light colored plastic clay from near the head of McLamore's cove, obtained from the Sub-Carboniferous series yielded (Mr. McCandless analyst):

Silica_______________ ________ _________ - -------- ___ 69.33

Alumina _________ ------- - -- - - ---------------- _ __ ___ _ 19.01 Ferric oxide___________ _ . ____ _- --- ____ _____ __ ____ __ 2.02 Lime_ ._____ _________ _~ ___ . __ __ _.. ___ . _____________ trace

Magnesia _ ---- -- _----- - - __ - - - ___ -- _-- __ __ _ 0.87 :Potash ________ __ _____ ._ .- ____ _______ - _ __ _ _____ 2.10

Soda____ _ -- --- -- _ - -- -- --- - -

0.1 '

Titanic acid (with alumina) -- - --- - ---------- - - --- - __ _ Water (hygroscopic) _______ .. __ ---- - - -- -- -- - -- -_ ___ ___ 0.26

Water (combined) -- - -- - ---- -- - - ----- - --- -- --- -- 6.88

100.65

ALLUVIAL CLAYS .
Most of the bricks of nort.hwestem Georgia are made from alluvial clays.
Good brick clay at Cartersyille occurs along the Etowah river. Mr. McCandless' analysis shows:

CLAYS.

287

Silica _________ -- - ---- ------- _ -- ------ - - ---- 69.18 lumina~------------- . ... . - ------- . ------ -- 15.43
Ferric oxide ._____ ___ _ ___ ----- - ---- ----- _ --- - -- 5.83
Lin1e _____ _ ------------------ --- ---- -- --- 0.00 Magnesia_ .. ____ _ . ___ __.. __ __ _____ __ _____ .. _. ____ . .. __ _ 0.71 Potash ________ . ___ _ . _ __ - -- ---- - .. _---- - - - - --. ---- 1.83
Soda . __ ------------- __ ---- ------ -- __ _ 0.15 Titanic acid (with alumina) - ___ _ ------ __ _ -- ___ ___ Water (hyg1 .~ opic ) . . ________________ _ -------- __ 0.22 Water (com bin d) -- . _______________ . ______ __ . ____ _ 6.61

99.96
This clay is derived from the washes of the metamorphic rocks along the Etowah river, and is remarkable for the absence of lime. Its composition shows a less degree of fusibility than the same clay at Rome which makes very beautiful brick. It is possible that at a few feet beneath the surface a still less fusible clay may be obtained.
The Etowah river clays are almost entirely derived from the metamorphic rocks to the east, and consequently they have a similar composition throughout the lower reaches of the river. At Rome the surface clay contains (Mr. McCandless, analyst):

Silica (free sand) ........

.. .. _ ----- 5b.80

Silica (combined) . _____ ... ------ ------- __ . .

17.00

Alumina ..

.. ------- ---------

Ferric oxide _____ _ _______ - ---- - __ ------

13.82 5.74

Lin1e __ ... _. _-- . . _---- -. - .- . - .. - .. -- - ---- -- --- -- - 0.00

Magnesia. _____ . ____ - --- _____ ---- .. ________ -- 0.81 Potash ____ ___ _____ __ ... __ .. - . ___ . _________ .... _____ .. 2.00

Soda __ _ ___ ----- --- - -- ---- - - - --- - - - - - -- - 0.55

Titanic acid __ _____ __ __ __ ------- - - - -- -- -- -- - 1.67 Water (hygroscopic) ____________ . _______ ____ . __ .. ___ _ 0.25 Water (combined).__ ____ ______ ___ ________ . _______ _ 7.35

99.99

288

ECONOMIC RESOURCEf;,

This clay is more ur less fusible, but makes good pressed brick. At a depth of about ten feet below the surface, a light colored clay less fusible occurs. This is of value alone or mixed with the upper clay. In composition it is (Mr. McCandless, analyst):

Silica (freesand)--- -------- - - - - --- ---------- ---- - 63.:W

Silica (combined)._ .. _ -- - ------ ------------ - - --- 14.30 Alumina ___________ ______ _ -- -- ------ ---- - ---- 10.90

Ferric oxide _______ ____ ___ ---------- - ----- -- --- 2.25

Lime ____ _ -- - - --------. ------ -- -- ---------- 0.00

lVIagnesia. ________ ________ _. ____ . _____ . _ _

0.63

Potash _______ ___ ___ _ . ____ __ -- - _ --- _ - - - ------ - 1.83 Soda . __ ____ - - --- --- . _____ ___ ___: __ ___ ___ ____ - 0.32

Titanic acid ___ --- ---- -.- - ------ __ ___ . - ----

1.98

Water (hygroscopic) -- --- -- --------- - ----

0.20

Water(combined).--- -- --- -- ---- - --- - ---- ------- 4.70

100.41
Such clay alone or mixed with the upper clay ought to make vitrified brick.
The analyses of these clays and shales will be of some interest iq connection with the analyses of the soils in studying the history of the clays, and in investigating their economic importance. The facts are here given without deductions, as the study is imperfect, for want of means of research, and the writer is not called upon to make deductions from insufficient data. The river clays, in many places, show two distinct types, as along the Etowah the lower clays are the lighter and less fusible. These clays or ad.:. mixtures of them are capable of making sewer tiles, and upon the eastern side of Lookout mountain, a few miles south of Chattanooga, and elsewhere, roofing tiles can also be made from them.

WATERPOWERS AND TIMBERS.

28~

CHAPTER XXXIX.
NOTES ON W ATERPOWERS AND TIMBERS.
WATERPOWERS.
There are many rivers and streams flowing over the .PaleozoiC' helt, but these have generally a slope not much above the base level of erosion, and consequently the shoals are not high ;: consequently the head of water on any dam would never be high, and seldom range more than five or six, or sometimes ten feet, but the discharge of water is often greater. On the edge of the metamorphic belt the streains descend much inore rapidly, and there greater heads of water could be obtained. Many of these streams furnish power for numerous s.mall mills, and others could be furtherutilized. Their capacity has not been determined, yet it bas been deemed best to give the generalized note as to the character of the shoals.
TIMBERS.
This is another economic subject which will be passed over in this report. For local uses there is generally an abundance of short-leaf pine and various oaks, and away from the present lines of railway much timber, including mountain oaks for tan bark, still remains for future shipment. The varieties of these timbers is. noted in the chapter on soils.

(19)

290

E CONOMIC R ESOURCES.

CHAPTER XL.
-THE LOCATION" OF ROADS AND THEIR RELATIONSHIP TO
THE PHYSICAL AND GEOLOGICAL FEATURES.
CONTENTS.
NO'l'E,-RELATION OF RoADS ro GEOLOGICAL STRUCTURE. ROADS ON 00STANAULA SHALE. ROADS ON K N OX DOLOMITE. ROADS ON CHICKAMAUGA SERIES. ROADS ON RED MoUNTAIN SERIES. ROADS ON FOR'l' PAYNE CHERT. ROADS ON FLOYD SHALES. RoADS oN MouNTAIN LIMESTONE. ROADS ON COAL MEASURES. SUMMARY. NOTES ON CoNSTitUCTION OF ROADS. SouRcEs OF RoAD MA'l'EitiAL.
NOTE.-RELATION OF ROADS TO GEOLOGICAL STRUCTURE.
As the topographical features and agricultural capabilities of any "l'egion are dependent upon the geological structure, so the roads ' bear au equal relation thereto. The roads give access-the features of the country favor or impede road-making.
The country of the Coosa basin is a great valley occupied by many longitudinal ridges trending from a little east of north to the opposite direction. These ridges are not constant, but are frequently broken, cut off, or thrown literally out of their natural positions. The smaller streams have added to the rugged features. 'Thus, there are great valleys extending longitudinally without .important interruption~. Also, there are subordinate and parallel

THE LOCATION OF ROADS.

291

valleys, between the heads of which there. are secondary divides. Some river valleys are 150 feet or more in depth, but the time since they were occupied by the waters to those heights dates back so far that they are greatly modified by atmospheric erosion, so that the greater valleys are generally bounded by more or less broken hills, and do not form rock-bound canons, like the upper Mississippi valley of to-day. The lower lands of these valleys are rolling, anu the streams usually flow near the surface. Along the greater river, the banks are seldom more than thirty feet above ordinary water. Such are the general conditions of the county through which the roads are needed.
The country west of Taylor's Ridge is of similar character, to which, however, must be added some mountain ridges and high plateaus.
ROADS ON THE OOSTANAULA SHALE.
Adjctccnt to the Coosa rive1' the country is generally undulating. The ridges are not great obstacles to road-making, but there are steep descents to the great rive ..s, which can be modified by hillside roads. In this region there are often gravel beds suitable for road metal. The sandy shales do not give rise to deep muds, but the more clayey soil'> hold the waters where the drainage is bad.
East of the Oostanaula Fault the border is characterized by crested l'idges, eastward of which the shales generally form valleys. This is true in most places, where the shales are in belts from one to four miles wide. In the northeastern portion of Bartow, and thence northward, the shales form many valleys, but there are numerous .\i ba l. - uv r 'I] i llitlt' v ui ng d dp. . Spenkin g gencral.l y tb t ~td s l'nnnin~ inn nor t heast ruuucl Ppposit dire in lntve!!O d ~fa ir g mrli ents, aml on. the ridge t h .gtA.(Ii nts ae no difficult. Except ~l ll l'O' .i11 th ' J'i <J re , Lt poll th e WC~te:m umder of h seri , , t;h rol.tds of' tlt is formaii n lla.ve g"l"tflierr t.hnt He ,. n roJly fuir

292

ECONO ~IIC RE SOURCES .

However, on passing from the heads of some subordinate valleys: to others, the divides are characterized by rough features, not seen along the principal highways. The sandy shales do not glve rise to the heavy muds seen in some other sections. The more calcareous portions of the river produce muddy roads like the red Knox lands.
West of Taylor's Ridge, the shales give rise to valleys of moderate width, with characteristic roads similar to those to the east.

ROADS ON THE KNOX DOLOMI1'E SERIE3,
There are two classes of gradients over this formation. In the red land-valleys, and on some of the ridges, the gradients are good, but in wet weather the muds are deep. Sante of the valleys are broad, but in the country characterized by cherty ridges (the western portion) iu Polk, Fh>yd, Bartow, and to a small extent in Gordon a.nd Whitfield counties, and in the counties to the westward,. the vallE>ys are often narrow.. The roads trending longitudinally bave good gradients in most of the large valleys, but in the narrow valleys, their heads are marked by heavy gradients. Hoadscrossing these ridges from east or southeast to the westward can sometimes be built so as to pass around the hills; but more ftequently tbey cross some portions of them, and then the grading may be vety bad, as ridges from 200 to 300 feet have to be ascended, and not always by gentle inclinations. These roads, apart from the main thoroughfares, are often very difficult of travel. And the "bad road" in a given region is only a relative expression; for on a so-called good mountain road, I have had a carriage wheel broken by weight of the load thrown obliquely upon it.
These sharp ridges have commonly loose cherty rock upon their surface, which could be used for road metal. Amongst the red lands of the Knox formation, the conditions obtain for good roads, but the mud may often be deep, the gray lands are more siliceous, and much less muddy.

THE LOCATION OF ROADS.

293

ROADS ON THE CHICKAMAUGA SERIES.
The limestones usually form valleys, often broad, with. good gradien"ts; however, there are some bold knobs or ridges in the Rockmart district. The residual clay of these limestones forms deep, sticky mud when wet, and afterward leaves hard rutted gror~ond. In many places the limestones, in variable beds, floor the valleys and form rough stony roads, where these are not properly built, as seen in vValker and other counties.
The shaly lands, in places, are in gentle undulations, but other slates form bold ridges, as near Rockmart. ThesB soils are commonly shallow, and seldom produce deep mud. There is u,;ually limestone for road-making in proximity to the Chicimmauga soils, which, more than any, need macadamized roads. The shale roads' .are often faidy good, without al'tificial improvement.

ROADS OVER THE RED MOUNTAIN SERIES.
Roads upon this formation are almost invariably across narrow ridges, along which there are no longitudinal highways. Amongst the shales, there is much siliceous material, and the muds are natumlly deep. There are always enough sandstones, or flaggy sand rocks at band for making good road material. This formation give<; rise to the bold ridges-Taylor's, Lavender and others noted.across which there are only occasional roads, which are steep, .owing to the ascent, of several hundred feet. Across the lower ridges, such as Shinbone, these roads are needed at only few localities, and the gaps are generally low.

ROADS OVER FORT PAYNE CHERT AND FLOYD SHALE.
This chert gives rise to crested hills which are often steep. Along these ridges roads are seldom constr.ucted, but highways often cross them. The surface is usually covered with cherty fmgments or gravel. Roads along the foot of such ridges are gravelly. The Floyd shale gives rise to sandy clays which do not produce deep

294

ECONOMIC RESOURCES.

muds, but often these are flat lands, and the ,'loil holds water. Some of the calcareous shales form a good road material.

ROADS ON THE MOUNTAIX LIMESTONE SERIES.
The residual clayey lands derived from these limestones occur only on the. sides of the mountains and in the narrow valleys between them, and ridges covered with Fort Payne chert. These clays produce heavy roads in wet seasons. Owing to the proximity of the gravel on the cherty hills good road-making material is at hand. On the mountain sides, where the limestones come to the surface, the roads are commonly rough, as the ledges of rock are not properly graded.

ROADS 01\ THE COAL MEASURES.
On the plateaus of these deposits, the roads are usually very sandy, but occasionally cross flat exposures of rough sandstones. On ascendi~g the mountains, the sandstones have to be crossed by the roads winding along the mountain sides to the top of the plateaus. As these passes are nDt generally well built, or when built, are subject to the greatest damage from rains, we find some of the roughest roads in the state-this condition arising from waut of properly constructed roadways, for the materials are at hand for building good highways.

SUMMARY.
Roads runmng northeastward and southwestward have been or could be located with good gradients. At right angleR, the ridges can often be avoided, but very commonly such is not the case, where the crossings are often poorly located and badly conBtructed. The roads on the soils derived from the Oostanaula shales have often good gradients, and the mud may not be deep.
The gray Knox dolomite ridges form a broken country, but the mud is siliceous and not deep. The roads on the red lands of the

'!'HE LOCATION OF ROADS.

295

series have better gradients, and are muddy in wet seasnns, followed by ruts through hardened mud.
The muds of the Chickamauga limestones are apt to be deep Th~ roads in the Rockmart slates are not deeply muddy. Materials for road-making are often conveniently near the highways.
The roads on Red Mountain series only cross the ridges, and the quality depends upon their gradients, as the material generally produces fine road beds, except when there are sandstone ledges, which produce rough roads that ought to be properly broken and macadamized. The Fort Payne chert gives rise to gravelly roads, which only cross the ridges. The Floyd shales produce sandy clay roads over flat lands.
The Mountain Limestones form muddy clay roads upon the mountain sides and in narrow valleys.
The Coal Measures originate sandy roads npm~ the plateaus; and tipon the mountain sides the sandstones produce rough, stony roads, where not properly b~ilt.
NOTES ON CONSTRUCTION OF ROADS.
The two greatest impedi'ments in gradients of the roads are: (1) the crossing of spurs in valley roads, when there is no obstruction that would have prevented the road being built around it; this condition is a too common blunder; (2) in crossing ridges or spurs t.be crest of the ridge is cut thus :

FIGURE 27.-Showing bad gradients of roads (abc), especinlly at the summit (D), which is rarely graded in keeping with the rest of the work.
This outline has in part arisen from some attempts at grading, which is often very good to ncar the crest, where the gradient is so

296

ECON,OMIC RESOURCES.

steep as to demand the greatest possible strain upon the horses in order to gain the summit, and then only to plunge down a declination of the same shape. This outline is not alone due to bad construction, but is the fault of nature and negligence of man. It .arises, in part, from the road washings during heavy rains. In every case the crest should be removed, for in its upper portion the strain is greater upon the animals than the tension upon the remainder of the ascent.
On the roads, crossing the ridges, oftentimes more gradual .ascents could be made. Throughout the belt surveyed, it may be .generally said that the roads running parallel with the ridges are fairly well located, with the exceptions mentioned.
The roads do . not generally, except as stated, become so "bad" .as in many clay districts of the north, or elsewhere, even in the state, owing to the more or less sandy constituents of the residual soil; still they need great improvements. With a snpply of road metal much of the district is provided already.
SOURCES OF ROAD MATERIAL.
In the region of the large rivers s01ne gmvel is available. The limestones of the Oostanaula shales afford numerous local supplies. The chert ridges of the Knox dolomite series, and Fort Payne <Jhert, are covered with loose macadam of excellent quality already broken up (see Part I. on the geology of the ridges). It has already been largely gathered for ballast by the Western & Atlantic Railway. This cherty mantle on so many ridges is only superficial, and its remoyal would be of agricultural advantage, and the day is <Joming when it will all be used for road-making, as there is not an excess of it. When this is consumed, or where it is too distant, the limestones already described will supply mauy localities with material for constmcting roads. Especial attention is called to the limestones of the Chickamauga series, \vhich commonly traverse belts of deep, muddy soils. Sandstones are inferior to limestones

THE LOCATION OF ROADS.

297

-for road metal, and such belonging to the Coal Measures are adjacent -to limestones which can be used in preference.
In a few districts attempts have already been made for improving Ithe roads: More has been done in road-making in the vicinity of Rome than elsewhere. The roads leading out of that city may well afford pride to the citizens.
But where the natural materials for road-making are not at hand, rthe day is coming when a denser . popula.tion will demand better bighways, and not only in cities but also villages will brick pavemlents be resorted to as in the numerous cases in other states.

298

ECONO:HI C RESOURCES.

CHAPTER XLI.
GOOD ROADS VERSUS BAD HOADS.
As a condition of good -roads, the location and gradients must be properly chosen, and after that the road bed, the local materials of' which have been indicated.
In Europe, there are few regions, even in the remotest country districts, from Sicily to Norway, where the worst roads are not as <good or better than most of our own best roacls. Apologetically, it has been said that it has taken generations to accomplish this, with a denser population. In france, the majority of the departments are more thinly populated than our northeastern States, and in Norway the population is 'more sparsely scattered than even in any parts of our own mountain regions. The old Romans had care for building good roads, it was necessa1:y for their :Qlilitary operations, even then long before the days of heavy artillery, still onl.v during the last two or three generations in most of Europe haYe good roads been common. Indeed, in old Europe, general good road making is younger than the American nation, therefore, our infancy cannot be pleaded as our excuse.
why has Europe generally built good. roads'? Because the people have discovered its necessity and profit. It is a paying investment, and no lnxury. 'Vould it be a luxury if a poor farmer, with a poorer mule, capable of drawing only a few hundred pounds or wood to a town, and getting fifty cents for it and his half clay's or clay's time, could with the same animal draw double or treble the amount? This is what they do in Europe. !sit a luxury to have roads such that the same animals, which bring two or three bale&

GOOD ROADS VERSL'R HAD ROADS.

299

of cotton, could bring double, and save the time of man and beast"!

This is what good roads permit. Are roads good enough, if ani-

mals can creep along and spend a day for what could be done in a

few hours, when the road is passable? In our field work, and on

good roads, I sometimes drive my camp wagon, etc., twenty or

twenty-five miles in the day, and do also seven or eight hours of

field work besides. But sometimes, it happens that the 1:oads do

not admit of traveling even this amount without accomplishing

any other work than changing locations. Do such roads pay:' Is.

it profitable to travel on roads, which rack the wagons t.o

pieces, so that in a year they require rebuilding. All of these roach;

are in this State, although many are in fair condition. But to-day th~ general feeling is everywhel'e alive, not in Georgia alone, but.

over the whole country, that the waste of money and labor is enor-

mous, simply because of our national bad roads.

In moderately dry seasons, with the roads well graded and.

ditched, many of our leading valley roads, owing to the commonly

sandy charact~r of the clays, ate or could be as good and better

than in many parts of the north, where the clays are stiffer and

mol'e liable to be cut into deep ruts.. But the grad!ents and drain-

age of the roads is often indifferent, and the crossings of the ridges.

are mostly indifferent, and often bad. In wet seasons, however,

most of the roads are rendered difficult of travel, and when cut

into ruts or "holes," the effects are left after the season becomes

dry.

The relative value of different kinds of roads may be seen from the

following table derived from experiments (Haswell's tables).

The traction or force reqnired to pull each ton qf a wagon loacl

oyer:

Pounds.

Good railroad_____ _

____ 7 to 12

Broken stone road iu perfect order _____ __ - ------ --- _ 30

Broken stone road in fair .order __ .. ___ . __ ____ _ _ . __ __ _ 56.

.300

ECO:\O.m RESOyR E, ',

Broken ston ' road, rutted __ .

- ----- _____ ------- -- - 10-!

Macadamized road (mor or lcs: rou<Th) ___ ---- --- _- _ _ _ _ 66

ommon by-road ____ ____ ----------- ------------- 212

'andy road good ----- -------- __ ------------ _____ - 12(i

Grav I road, new _---

---------- --- - 16()

L oo. and road __ __ _ __ _ - _________ - -- --- -- --- - - _ 500

In \\'et weather tb mud road. become far worse than tbe ;;;andy

Fro RE 2 .- Country Roud in Frnnce (nfter Potter).
'road , o that in the !e ng rn n ev n these are ex pen ive. On au.dy road - the traction i: a lway s o high a to make the roads very

GOOD ROA~S VER.'US BAD ROADS.

3o r

co tly. In Georgia, seldom are loa]. carried whi ch exceed a ton . Upou t he hard road in France a team of three h o r~;e. drawv a load of four ton , and co nsequently, th e cost is propo rti onally reduced . ( ee fi g ure 28 .)

FtGURE 29.-Mucl Road in America (after P otter) .

FrouK~; 30.- A. com mon co untry road- " rath er good." (After P otter ).

.3 02

E 'O XO;\riC R ESO R CE. '.


Th e poo r road not m rely recl nce th e load carri ed but le. en,

t he eli tance whi ch can be tla,eled, an l t he life of th e a nimal. Even

o n a good . andy road, it take. mor t han twice th e force to ch a w a

load a. it doe on a fait Rton r oad , or four time a much as on a

Fw R E 31.-Cou nt ry rond in l' m ncc (after P otter ),
good ton e road, both of whi ch are a,ailable in a ll weath er. Bu t in wet seaso n , th e toad.- may beco me impa. ,;;ab le, and e,e n a n
mpty wago n can . ca rcely be ttansportcd t hrough th e mud.

GOOD ROAD.' YERS S BAD ROADS .

30;3

Figute 29 repre ents a road almo. t in sight of a $25,000,000 ~apitol , voted for by the fiumers ; but it can be reprod uced m Georgia.
A common type of fair road is represented in fi g ure 30. In co ntm t, on e may sec almo:t anywh ere in France a co mmon, hard, smooth roadway, and uch ate ofte n shaded with tree , g ivin g comfort to the anima I , so necc at-y in our warm climate (fig ure 3 1). D oe such a co ndition as pictmecl in figures '31-33 occur here?

FLOURE 3?.--Country roud in Ituly (after Potter ).
Even where tree are sti II standing by th e r oad . ide, how often has one .ee n them ruthl c:. ly removed for fear of shadin g a cotton or a co m field, alth oug h th ey ca nnot do harm , a. when located ~pon th e onth ern : ide- of hi O'hway., 'rith ca:ting shadows upon the

304

E CONOMIC RESOURCES.

roads and not upon t he fi elds, giving breath and refreshment to thepantin g mule or horse.
Such an idea as cuttin g t hrongh the sp ur of a rid ge in place of a difficult climb over the hill has not yet obtained amongst u., a i. the ca e in rural France (fi gure 33) .

Fw RE 33.-Country road in France (after P otter).
If t he sto ne roads are bad Iy constructed and allowed to be ru tted, they are scarcely better than andy road., and much worse than clay road , except in wet weath er.
In _tmn portation, a team cannot convey a load g teatet t han it can draw over t he wotst part of the roads. It is not sayin g too
much that the cost of bringin g much of the cotto n to mark t i ~

GOOD ROADS VERSUS BAD ROADS.

305

double or treble what it should be, if all the roads were in good order. Indeed, the cost of these few miles of transportation is commonly greater than that of conveying it from the market to the seaboard. If the time of the man and mules were allowed for, the cost. of marketing every one of the 900,000 (?) bales of cotton, sold in Georgia in 1890-'91, would not fall below a million dollars. Half of this cost, at least, could be saved with good roads, and thus, one application of poor roads alone is seen to cost the State $450,000. a year. But this question of loads of inferior weight is not all, for on muddy roads, the conveying of heavy loads must temporarily cease entirely, with a loss of time that is reducible to money. Not to be invidious, let us quote from roads of another State, where however, the conditions for continuous bad roads prevail to a greater extent than in the section of Georgia under survey. In one county there were ten thousand horses, the feeding of which at twenty-five cents a day, cost $70,000 for four weeks. During four weeks the roads were in such a condition that teaming was out of the question. The horses were idle in the stable. It cost the county at least this amount-the bad ro~ds did. Are there not also many examples in our State? A student of good roads has calculated that in Indiana bad roads cost at least fifteen dollars per horse per annum. This is not an extravagant estimate, allowing for food and loss of time.
In 1890 there were over 721,000 horses and mules in that State. This loss from bad roads amounted to $11,000,000 to the State of Indiana for one year. Apply the same estimate to Georgia which had 271,:329 horses and mules, and over $4,000,000 worth of feed and labor were lost, because of bad roads.
Another point may be emphasized, the common absence of bridges over many streams. The sides of the streams are often steep, and the approaches to the fords are difficult and dangerous. The bottoms of the creeks are covered with large stones, which
(20)

306

ECOXO:MIC RESOURCES.

rack the vehicles, as they cannot be avoided. The strain on the horses, the wear on the wagons, and discomfort to the traveler, are nothing compared with the loss in utilizing the animal power. Often with an excellent pair of horses, it has -been the greatest labor to cross streams with a load of half a ton weight; and this for horses that could easily pull three tons on a first class road. These fords ought to belong to the past. The approaches to the ferries are commonly little better, and these ought to give place to bridges, as they are frequently doing. Besides the difficulty of the fords, in high water, long detours, or even delays of days, are necestary. On one occasion, a storm came up at night. \Ve were assured that the ford across a branch, thirty feet wide, was sate at the higher stage. We entered it; one horse was floated off his feet, and the body of the carriage and contents submerged; with difTI.culty the opposite bank was reached. The delay, owing to the bad roads, caused us to miss the train. This incident and the damage and delays cost the State alone more than enough to build a bridge over this stteam.
The good roads of Europe are often modern. The generally excellent roads of Britain date bacl{ no farther than seventy years ago; and those who advocated them were satirized as visionary. ~Iany of Italy's best roads have been made in the last quarter of a century.
Most European countries place the roads under the control of the governlllent. :France is a republic of small farmers, and they get something from their government in the form of $18,000,000 a year for road repairing, etc. If our State would only expend for a few years as much money as is lost every year to the farmers by bad roads, then Georgia would have highways equal to those of any country. What was good enough for our grandfathers and our fathers, will not do in the age of progress and competition, when the greatest amount of work must be done for the least amount of labor.

GOOD ROADS VERSUS BAD ROADS.

307

About Rome, there has been the application of convict labor to

the public roads, under competent direction, and this district shows

what may be done. It is an object lesson, and one can ride with

some comfort in stormy weather and not find himself belated. But

whether road improvements be made at State or local co::>t, they

must be laid out by competent engineers, and constructed under re-

sponsible supervision, and not under neighborly direction at a

semi-picnic frolic.

It has been estimated that the loss occasioned by bad road::> costs

the United States no less than $350,000,000 a year. What people

do not directly pay for, they do not feel, but he who provides

against losses is the thrifty and well to do man, and so with States;

for extravagant wastes and the gloomy side of bad roads ought not

to be perpetuated.

The bright side of good roads is not merely in dil'ect profits, but

the increased value of lands and the increased comfort in travelling.

A country without railroads is cheap to-day. A district from

which it costs more to convey the product to the nearest market

than from it to the markets of the world must also be cheap. This

cheapness is overcome by good roads.

In another State, cmnks, we are told, wanted good roads. They

were ridiculed_; one man built a mile of good road at his own ex-

pense. This object lesson, rising above laughter, soon resulted in

seven good roads through his county. Not far from a great city

a farm was worth fifty to seventy-five dollars an acre, but could not

be sold. The owner farmed at a loss. At last, a good road was

built, and the land was then sold for $200 an acre, with facilities

for turning it into a truck farm.



As t~is question of roads is one now attracting great attention,

both in Georgia and elsewhere, the digression of the subject may

be excused, as duty has carried me into the question of the relations

of the roads to the geological formations of northwest Georgia, and

the materials for their improvement.


PART III.
SOILS
OF THE
PALEOZOIC GROUP
OF
GEORGIA,
IN POLK, FLOYD, BARTOW, GORDON, :M:URRAY, WHITFIELD,
CATOOSA, CHATTOOGA,WALKER AND DADE COUN'l'IES.
BY
J. W. SPENCER, PH. D., STA'rE GEOLOGIST,
AND I
H. C. WHITE, PH. D., PRESIDENT OF STATE COLLEGE .
(309)





SOILS,

311

AGRICULTURAL FEATURES
REPRESENTED ON THE GEOLOGICAL MAP.

COAL MEASURES . . .. ... . . Table lands, poor sandy soil.

MOUNTAIN LIMESTONE . Mountain sides and valleys, fair soil.

FLOYD SHALES... ... ' .. Flats or valleys, thin soil.
-
FORT PAYNE CHERT..\ .. Gravel ridges, little soil.

CHAT. BLACK SHALES . . . Narrow valleys, no surface soil.

RED MOUNTAIN SERIES .

Crested ridges, little soil except on sides, there fair.

CHICKAMAUGA SERIES . Valleys and some ridges; good soil.

KNOX DOLOMITE . . ... ..

Gray cherty ridges, gray and red plain and valley lands; latter very good soils.

. OOSTANAULA . .. ' .........

Wide valleys, good soil; ridges, thin and poor soil.

METAMORPHIC FORMATIONS ..................

Mountain ridges and valleys, on the border of the Paleozoic group of rocks; this soil often thin and poor.

312

ECONOMIC RESOURCES.

CHAPTER XLII.

FORMATION AND CHARACTERISTICS OF SOIL OF THElPALEOZOIO BELT OF GEORGIA.

CONTENTS.
COLOR DISTINCTIONS. ORIGIN OF THE MATERIALS OF THE SOILS. How THE SoiLS WERE FoRMED: The Formation of Limestone Soils as illustrated
from the Knox Dolomite Series; Sources of Plant Food in Limestones; Formation of Shale Soils; F<Jrmation of Sandy Soils; Formation of Creep Soils; Formation of Alluvial Soils. ACCUMULATIONS AND EFFECTS OF ORGANIC MATTER IN SoiLS. KINDS AND PHYSICAL PROPERTIES OF SoiLS; Sandy Soils; Clay Soils; Calcareous and Marly Soils; Fenuginous Soils. RELATIONS OF HEAT AND MOISTURE 'J'O PHYSICAL STRUCTURE AND CoLOR OF Sons: Sandy Soils; Calcareous Soils; Clayey Soils. NECF~SARY CoNSTITUENT~ OF PLANT FooD: Elements; Medium of Supply; Fixing of Plant Food; Supe.rphospbate of Lime; Potash Salts ; Ammonia Salts. EsTIMATING THE VALUE OF SoiLS: Value of Analysis; Lime; Phosphoric Acid; Potash; Soda; Sulphuric Acid; Chlorine; :B'erric Oxide; :M.oisture; Physical Conditions. CONSUMPTION OF MINERAL CONSTITUENTS OF PLANT FooD DY COTTON, CoRN AND WiiEA'r.

COLOR DISTIXCTJON8.

There is a popular classification of Georgia soils into gray, mulatto and red lands. In limited regions, this distinction is descriptive, where the superficial earths me derived from the same

general rock formations.



But to apply the terms generally, whether to the Pleistocene

soils of southern Georgia, formed by sedimentation in great bodies of water ; to residual soils of central Georgia, derived directly from the decay of gneisses and other crystalline rocks; or to soils made
- out of decayed limestones or shales in northwestern Georgia, is to

SOILS.

313

imply that the value of the soib is independent of the components or of the formations to which they naturally belong. However, in the price of land, there is a differentiation, for under equally favorable conditions, the same colored lands are much more valuable in some districts than in others, and this difference is dependent upon their composition, which may not appear to the eye.
TM.e deep color is given to the land by oxides of iron, or modified by traces of manganese, and by organic matter. This color is associated with certain textures which have general influences in absorbing the solar heat and consequently affecting radiation. All of these conditions bear upon plant growth; but the heat effects are independent of mineral food, hence the color designations are of value only when applied to soils as indicating that they arP. derived from different rocks, in the same region and that the;:;e rock8 and their decomposed products have different enmponents. Thus in central Georgia a red soil may indicate its derivation from a hornblende gneiss or granite, whilst a gray soil is formed out "of ordinmy gneiss or gmnite, which has a different composition from the former; accordingly this color definition has only local values; as for illustration, in portions of north western Georgia, reel and gray soils are both derived from the decomposition of the Knox dolomite; the dark soil, howeyer, is formed ont of the less siliceous beds and are more calcareous, with more phosphoric acid, etc., than the gray soil derived from the cherty and siliceous beds which are sandier, !ltonier and poorer in certain plant foods. But these two classes of soils in .Q1icldle and northwe.3tern Georgia cannot be correlated or separated by their color lines. Indeed, locally, there are other conditions which render their generalized elassification still weaker: as an example; there are red loams upon many bills adjacent to the greater rivers. These soi Is are often very difficult of distinction from the red lands of the Knox dolomite, when the formet have no gravel8 Msociated with them, but the derivation and composition are quite different.

314

ECONOMIC RESOURCER.

THE ORIGI~ OF T!-IE MATERIALS OF THE SOILS.
Primarily, the clayey, the sandy, and part of the. calcareous components of the soils are derived from the decay of the metamorphic rocks of the east and were laid down along the western coast of the ancient lands of middle Georgia. The .calcareous matter, howevet, was in a great part absorbed directly from the sea water through the agency of animal life ann converted into limestones. But the qnestion now is, not the origin of the rocks of north western Georgia, but of the soils from these rocks. These rocks were largely limestones, shales and some sandstones, and these materials were commingled in various ways, so as to form impure beds of various kinds; accordingly we find that the shales are usually ~ore or less calcareous. The magnesian limestones often predominate over the simple limestones; but in either case, they are of various degrees of impurity. The sanclstones are also more or less argillaceous. From these rocks the soils have been formed.

HOW THE SOILS WERE FORMED.
~early all the soilfl of northwest Georgia are re~idual, that is, the remains of the rocks decayed in place.
THE FORMATION OF LIMESTONE SOILS AS ILLUSTRA1'ED BY THE KNOX DOLOMITE SERIES.
The Knox dolomite formation occupies a very broad country, and to the formation of its soils prominence is due. From the analysis of the limestones given (pages 263-271 ), it may be seen that many of the dolomites, which contain t=wen a smaller amount of impurities, hold as much as 3.75 per cent. of silica or sanc1, .and 1.5 per cent. of alumina .(with a tmce of iron). Other compact rocks consist of as mnch as 6.25 per cent. of sand, whilst the impure earthy limestone, such as prodnces cement, contains 22 per cent. of silica, 5 or 6 per cent. of alumina, 1.5 to 2 per cent. of ferric oxide. Here, then, are the materials for the red soil of the formation. The action of carbonic and of organic acids dissolves away the calcareoufl .

SOILS.

315

matter, leaving the silica, alumina a.nd oxide of iron, etc. This decay is unequal upon even the same bed of rocks, as is seen in plate III., opposite page 43, or in figure 34.
T

Figure 34.-Formation of Soil from decay of Limestone. Shaded portion represents the residual enrtb (r) derived from the decay of Limestone (k).
Upon studying the analyees of the soils it appears that tboee formed fl'om the 01dinary Knox dolomite contains about 67 per cent. of silica, and some 5 or 6 per cent. of alumina, whilst others contain 12 to 15 per cent. of alumina, besides iron, etc.
As the calcareous matter is dissolved out of the rocks, the alumina and silica remaining form clay and free sand, easily acted upon by the rains and rills, in which case much of the clay is carried off the surface as mud into the rivers, leaving an excess of sand to form sandy loams. Thus, it may be seen that the ordinary soils derived from the limestones contain about ten times as much silica as tpe original rocks did. Accordingly, the conclusion is reached that at least ten times as much limestone as there is silica in the re5idual earth has been removed. In one case the residna~ clays are known to be two hundred feet deep. These would accordingly, represent the remains of two thousand feet of limestone;; th~t formerly existed in this locality. Some of the silica has been washed off with the alumina, and so this estimate may be below the mark. Otf1'er s6l'ls derived from the Knox dolomite formation contain from 80 to 82 per cent. of silica. Such are derived from the flinty portions of the

316

E CONOMIC RESOURCES.

series, which were much richer in silica. These flints were concretions in the limestones, and contained crystalline particles of the magnesian limestones. Upon weathering, the calcareous matter bas leached out, and there remains the flint or chert matter full of cavi-
ties, .and eventually, much of it disintegrates into a. sandy soil.
Along with this comminuted matter, the soil is also more or lesR charged with cherty gravel.
As the Knox dolomite has many layers rich in the chert, so there is a variety of soil arisit:g from tbe same format.ion. The less siliceous beds of the rock usually contain the largest proportion of iron compounds, which produce the residual red soils, generally more aluminous or clayey. Here then, is the basis of the soil derived from the limestone, hut the plant food is not yet mentioned.

SOURCES OF PLAN'r FOOD IN LIMESTONES,
The calcareous matter of the sea water is secreted by shells, crinoids, corals, etc., and the remains of these animal:; form the limestones built beneath the sea.
Except portions of the flinty matter, which are also of organic origin, the siliceous matter or sand and clay have been canied down as silt and deposited along with the growing limestone. This clay arises from decomposed feldspars, and contains the alkaliespotash and soda still in a state of combination. So also some phosphatic matter is deri\'able directly from the crystalline rock, and is held in the mud. But a considerable proportion of it is also secreted by the organisms forming the limestone. The iron and manganese were chemical deposits amongst the forming rocks, the matetials being carried down by streams. The sulphuric acid may be of chemical origin, directly or indirectly derived from the sea water, or sometimes of organic origin and may exist as the sulphate of lime, or as the sulphide of iron. The magnesia, so commonly combined with the lime, is directly derived from the sea water, by a process not known.

SOILS.

317

We now see how the plant food is locked up in the limestone rocks. Upon the decay of the rocks more or less of these constituents are not leached out, and upon their presence the value of the soils in a large measure depends.
Usually the limestone contains ~orne organic matter, often 3: considerable pe~centage, but this original organic matter is in the con~ clition of bitumen-like compounds, and is not in the form of plant food. There are other limestones, such as that of the Chickamauga series, which gives rise to heavy clayey soil.
THE FORMATION OF SHALE SOILS.
The shales in the country under examination are all calcareous, and many of them contain beds of limestone. From this calcareous matter, the fertile constituents are principally derived. These shales are highly siliceous, and in some places the subsoils are mostly made up of small shaly fragments or shingle. In other cases, it is a sandy clay, resembling the Knox dolomite soils, and deeply stained with iron.
'fHE FORMATION OF ~ANDY SOILS.
These are usually formed from the disintegration of sandstoneP, which, if they contain clay impurities, become more or less loamy; if not they are usually light and poor. However, some of the shale and especial'ly the Lafayette soils, are very siliceous, and from them much clay is often washed away, leaving sandy surfaces. Overflows along the river lowlands also leave local sandy deposits.
'l'HE FORMATION OF CREEP SOILS.
In the lower parts of the valleys, and upon the hillsides, there
are various clay soilH which owe their origin po the gradual creep-
ing down of the more clayey materials from the higher ridges. In characteristics, the soils partake somewhat 'of the nature of alluvial deposits, but the materials are not assorted to the same extent.

;)18

ECONOMIC RESOURCES.

FORMATION OF ALLUYIAL SOILS.
Such soil is formed out of the muds deposited by nvers or in estuaries. On the hills adjacent to the larger streams, in the belt snrveyed, to an elevation of one hundred and fifty feet above them,. there are the remains of alluvial deposits with often a bed of gravel beneath. These aecumulntions represent the remains of a sheet of mud belonging to recent geological times, which bas been correlated with the Lafayette series of sonthern Georgia (see part I. of this report). The heavy loams do not usually extend more than two miles from the large streams. Since their deposition, they have been greatly denuded, and only remain in broken patches. They are o f'ten liable to be mistaken Jor the red residual clays of the Knox s~ries (when no gravel is associated with them). These loams are apt to contain more aluminous matter than the residual clays, and hence, they are somewhat heavier soils.
There are other and more modern alluvial deposits formed by the overflow of the rivers, but such are not widespread, and are very local.
Under these conditions, almost all the soils throughout northwestern Georgia are simply those formed out of the remains of rocks decayed in place.
ACCVMULATIONS A~D EFF~CTS OF ORGA~IC MATTER IN SOILS.
It has now been seen how the physical body and mineral plant foods of soils have been derived from the rocks. For the growth of the higher plants, they need nitrogen in a form which can be assimilated. In course of time the rock dirt becomes soil through the agency of pla.nts. The living plants send out their roots and loosen the earth and render it more porous. They also mech~n icitlly prewnt the washings of the surface. The covering of the surface prevents e-~~~pe, of.carbonic acid and other excretions, which act u pun the underlying materia Is and r~nder them more soluble. Part of this assimilated mineral food, gathered often from depths in the ground, is thus accumulated at the surface; and upon the decay of

SOILS.

319

these plants, this food is in the most favorable conditions for absorption by new growths. Trees often bring the food from depths of four, six or occasionally fifteen feet below the surface. The conditions of greater availability of plant food from the surface soils, than from greater depths, is best shown from the systematic analyses of the _earth of different depths. In our report upon the soils of the Agricultural ExperimeutSt.ati0n of Georgia several analyses of earths taken at different depths are given. (See that chapter as a sequel to the report on northwestern Georgia.) From these results, we find that the soluble lime, potash and phosphoric acid diminish rapidly with depth from the surface. 'This solubility was determined by allowing the soil to digest for thirty days in diluted hydrochloric acid. These soluble portions of the constituents may be cGnsidered as available for plant food, the insoluble only after long action of decomposing acids arising from vegetable decay.
At the Experiment Statio~, in descending from the surface soil to 42 inches, the proportion of lime which is soluble diminishes from 83 to 47 and then to 37 percent.;the available phosphoric acid from 50 to 25 and then to 8.5 per cent.; and the the soluble potash diminishes from 42 to 13 and then to 8.5 per cent. of the total amount. A second set of analyses shows similar results, except in the phosphoric acid, which is mote soluble at lower depths, but there, the character of the strata changes from mixed soil to decayed and porous rock.
In a series of experiments conducted by Mr. D. \V. Langdon at Tuscaloosa for the Alabama survey on soils ranging from the surface to a depth of fourteen feet, the total amount of soluble lime, potash and phosphoric acid dimini~ed from the surface to 7.5 'feet, below which the available elements were in scarcely more than traces. His report did not give the total amount of the constituents in the insolubLe condition. &lme analyses on the soils and subsoils' by Prof. Loughridge in .Pofk and Bartow counties gave the same results.

320

ECONOMIC RESOURCES

This greater availability of the plant food 1n the surface soils than below arises from the solvent effects of carbonic and vegetable acids upon the necessary elements-not only those named above, but otp.er mineral constituents which are equally necessary for plant growth, and which are usually present in sufficient quantities in the soil.
From some of the analyses we find that there are absolutely larger quantities of the elements which form plant food atthesurface than at greater depths. This, in some cases, may arise from the variations of the soils at different depths, being derived from somewhat different sources, bnt as the increase is largely amongst the soluble constituents it is evident that the greater quantity has in part been accumulated by the long successions of decaying plant life which has flourished at the surface.
The organic substance called humus is a mixture of decomposing matter, forming transition products which often act energetically upon the soil. The name humus is given to the yellowish or dark brown pulverulent organic matter. This dark humus has the power of absorbing moisture, and the soluble substan.ces contained in it. The humus when combined with clay forms a moist pulverulent soil or vegetable mould. In contact with alkalies or lime it absorbs oxygen, both from the air and from oxygen compounds in the soil, thus acting as a reducing agent. Accordinglythis humus has the power of fixing in the soil many of the necessary compounds of plant food. In this oxidation a series of organic acids is found which ultimately ends in carbonic acid and water. Prof. A. A. Julien's expe~iments on rock decay show that these vegetable acids have greater decomposing effects upon minerals than even catbonie acid, and also dissolve various alkalies, silicates, etc.
The decomposition of the vegetable components also converts parts of the nitrogen into ammonia and nitric acid, from the compounds of which it is again absorbed by the succeeding generation

SOILS.

32'1

of plants. Humus also acts as a solvent of ammonia derived from the atmosphere.

KINDS AND PHYSICAL PROPERTIES OF SOILS.
Sandy soils are composed of rounded or angular grains of sand, which are usually quartzose, but often with particles of other undecomposed rocks, or with an admixture of clays. Pure sandy soil is sterile, but when it contains clay or minerals which make clay upon decomposition it may become fertile. The sand is porous and permits the escape of water. It also absorbs solar heat quickly and cools quickly, but if the grains are fine, or it becomes earthy, this property of sudden absorption decreases, and the power of" retaining heat increases. The sandy soils are warm and dry, and when they contain humus or clay they may suffer from drouth .. The available plant food is in a condition of easy absorption, hut: without a supply of foreign food the soils are not durable.
Clay Soils.-Pure clay or hydrous silicate of alumina is not w fertile soil. Clay soils contain more or less free eand ('vhen in excess this forms a sandy loam), and various other constituents, as lime, iron, etc. Clay has the property of not only retaining plant< food, but when such is in solution it absorbs a large percentage of' it from water passing through the earth.
Clays are colored yellowish, brown or red by ferric oxide in dif- ferent conditions; blue or gteen by ferrous oxide; pink, brown or blad\.: by manganese; gray to black by humus. Clay absorbs moisture and swells np, thereby retaining its water and producing cold soil. But the dry clay retains heat. Moist clar is usually plastic,. but this plasticity is reduced by the presence of lime. These plastic clays are tough when wet, but crack upon drying and expo~-;e the roots of the plants. During long wet seasons the heavy clays. favor the reduction of iron compounds to the condition of ferrous oxide, which is injurious to plants. Few of om clays are heayy,
(21)

322

ECONOMIC RESOURCES.

but they are mostly mixed with free sand, which reduces them to the condition of loams, with the accompanying advantages OYer both heavy clays or loose sandy ooi!R. But these loams vary greatly.
Calcwemts and Marly Soil.s.-Every fertile soil is more or less calcareom;. This calcareous mattet may be in the form of grains, constituting calcareous clays or loams. But the lime is often in the form of an impallJable powder intimately mixed with the clay, cons\ituting a marl, by which name it usually goes when it contains 10 pet cent. of lime. Calcareous soils are stiff, but they are pulverulent when moderately moist, and very productive on account of the mineral promoting decomposition of organic matter, as well as easily supplying this elt;Jmer~t to the plants. Lime also renders day more porous.
Ferruginous Soil.-Most soils contain an abundance of irou. The :iron in the condition of ferric oxide giving it the red color favors Jhe absorption of solar heat. In its hydrated state it absorbs 1moisture and retains the soluble plant food. It is apt to form harcl .concretions in the clays. The ferric oxide is beneficial, except \W hen it is more or less protected from the atmosphere and in contact with vegetable matter and moisture, when the ferron.~ salts are genemted, which blight plant life. In such cases drainage is parJicularly necessary.
These conditious pre\'ail in swampy lands, so that they are sel.(loru productive until long after dmillage, when the iron has been / exposed and converted into ferric oxide.
iRli:LI\TION S OF HEAT !ND MOB1'CRE '1'0 PHYSICA L STRUC'fURE AND COLOR OF HOILS.
These have been summed up as follows: "Sandy soils, when of dark colors, are most heated during the day, and cool down most during the night, and, in consequence, condense most clew; but sandy soils of light colors are rapidly heated beoouse of the coar~eness of the gmin~ while they retain well

SOILS.

323

the heat so absorbed because of their color, and such soils condense

comparatively little dew.

"Calcareous soils, well pulverized, when of dark color, are

strongly heated during the day and retain their heat well at night

in consequence of their fine grained texture, and condense little

dew; when of light colors, are very slowly heated by day and

cool very slowly at night, and so also condense little dew.

"Clayey soils, when very dry and of dark colors, are strongly

heated by day and retain their heat at night; when of light color,,,

are slowly heated by day b,ut retain their heat.

" Clay soils, when well moistened and of fine pulverulent text-

ure, soon allow the moisture to evaporate and then become warm

and remain so; but when of light color retain the enclosed moist-

ure because they absorb less readily the heat necessary to its

evaporation, and remain long cold.

''Clay soils, thoroughly wet, and of the consistence of soft mud,

are very slowly warmed, but once heated, remam warm, while

those of light color remain long cold and wet." (Prof. E. A.

Smith.)

He also adds that:

"A sandy soil is kept uniformly warm and moist for a long time

by a subsoil of clay; whilst a cold, wet clay soil is warmed and

dried by a subsoil of sand. A loose covering of stones as well

as vegetable matt~r protects the ground from both extremes of

heat and cold, and then shallow soil per se is subject to extremes

of temperature."

.

NECESSARY CONSTITUENTS OF PLANT ]'OOD.

Elements.-Plants contain the following chemical elements: carbon, hydrogen, oxygen, nitrogen, phosphorus, sulphur, chlorine, iron, magnesium, calcium and potassium. Besides these elements, silica, alumina, manganese, sodium, etc., in small quantities are found in plant ashes.

324

ECONOllfiC EESOURCJ,S.

Medi1tm of Supply.-Of these substances, the carbon, as carbonic acid, is mostly absorbed from the air; the hydrogen and oxygen in the form of water, are a main supply of plant food derived through the soil; nitrogen, as ammonia and nitric acid, or compounds of these, are derived directly or indirectly through organic remams.
The other elements are chiefly mineral, and are taken front thesoil which contains them in small quantities.
Fixing of Plant Food.-In writing of the original sources of tl.te soil, a portion of the constituents of plant food has been shown to come from the decomposition of the rocks. But this is. not the only f:iOnrce. In the soil the hydrous clays, hydrated ferric oxide, hydrous silica, etc., can absorb and fix mineral conf:itituents-dissolved in waters percolating through them. Thus potash, ammonia, lime compounds, phosphates and silicates are largely absorbed, whilst those of soda and magnesia, chlorine, sulphm and nitric acid are absorbed only to a very sma ll extent. But some of the solutions of the above substances lJaYe th e powet of displacing others; or most of them may be more oJ" less war;hed out again by an exceso of water passing through the soil. The surface Hoi! fixes a larger amount of salts than the deeper earths.
In our soils the co mpounds which are mo1;t affected by ~/:row ing crops anrl oooneot need rfplacement-ell;c!usive of organic compounds-are phosphoric acid, potash and lime, especially the two former.
Snperpho.~phate of lime soon becomes insoluble in the soil, owing: probably to the excess of lime in the soil. It is rendere d still more insoluble by the reaction ot' the iron and alumina, but it is left in an extremely finely diYided state, in which condition it is easily absorbed by the plant.
Pota.~h Salts are absorbed by hydtous clays, fenic oxide, hy-
drous silica, etc. Accordingly, in the formation of soils, and leach-

HOILS.

025

ing by atmospheric waters, plant foods are left in a greater or less quantity.
Ammonia Salt8 are mostly absorbed in a way similar to those of pota<;h.
ESTIMATING THE VALuE OF SOILS.
Vcdue of Analy8es.-Soil analyses of themselves are not always indicative of the quality of the soil, as the plant food may not be available. It is this tempomry propetty that leads agriculturists to turn out fields t0 rest, ot' better still to fallow, or plow the fields without cropping; thus affording opportunity for disintegration of mineral ingredients, and the rendering of them available for plant food.
Analys(~S are valuable wheu they prove the absence of plant food below the limit of fertility, and they show what i.> most needed. Prof. Hilgard's long careful studies have shown that a valuati(ln of the soils may be derived ftom the analyses, when based upon solubility of the r.omponents, and in this case rejects those portions of the elements of plant food which are not soluble in diluted hydrochloric acid. In the analysis of the soils given in this report we have the quantity of both the soluble and in:-;oluble lime, potash and pho;,:pboric acid, upon which deductions can be based.
,Lime.-Ptof. E. vV. Hilgatd ha;; found that the percentage of
available lime present in productive l:loil must not fall below 0.100 per cent. in t.he lightest sandy soil; in clay loams not below 0.25; and iu heavy .clay soils not below 0.5 pet' cent., and better still, 1vith even 2 per cent., above which it i~> of no special value, except mecl\anically.
Pho8pho1ic Acid.-If the pho~:>phorie acid be less than 0.05 per cent. there is a serious deficiency. In sandy loams, with lime 0.10 per cent. of phosphoric acid renders soil fairly producti\e for eight or fifteen years; if lime be deficient, double the amount is required. He has fuuud the soluble pho~>phoric acid present in splendid table-

326

E CO NO~IIC R ESOUR CE S.

lands of the Mississippi river to the extent. of .30; whilst on the black prairie of Texas, it bas amounted to 0.46 per cent..
Potash, if present to less than .06 per cent. in soils, shows them to be deficient in alkali. Deep sandy soil with less than 1.00 per cent. may be productive. With the amount of clay in the soil, the potash increases. In 8andy loams it fall below .30; in clay loam:'; it ranges fl'Om .30 to .50 per cent.
Soda to the extent of from one-eighth to one-third as much as the potash is sufficient.
Sulphuric Acid to the extent of 0.02 or 0.04 is adequate. It rarely amounts to more than 0.1 per cent.
Chlorine is of only slight importance. It is always present in sufficient quantities.
Fer-ric Oxide is a necessary plant food perhaps, but Hilgard finds its greatest benefit derived from the absorptive power of ferric hydrate. Red lands resist drought better than light colored lands. (The moisture also depends upon humus, clay and lime.) The per:;entage of iron varies. From 1.5 to 4.00 per cent. in some conditions may only slightly tint t.he soils. But the red lauds may contain 12 or even 20 per cent. of ferric oxide as previously noted. Red lands also appear to be a carrier of oxygen and facilitate nitrification, even though the soil contains a high percentage of humus. But damp red lands (from bad drainage or overflows) reduce the ferric oxide to ferrous salts which blight the crops.
Moistwe.-At 60 Fah. cultivatabl8 soils contain from 1.5 to 23 per cent. of moisture. Pure clay seldom exceeds 12 per cent., ferruginous clays and also calcareous clays 1.'5 to 21 per cent.; and in peaty soil it may rise to 23 per cent.
Physical Condition.-Beside the chemical composition ofthe soil, its physical characteristics have a strong bearing upon its agricultural value, such as texture, abs0rption of moisture, heat, etc.; and the physical features of the land, bottoms, plains, hillsides (steeper than 20 are almost 1 navailable), etc.

SOILS.

327

THE CONSUMPTION OF MINERAL CONSTI'l'Ul~NTS OF PLAN r FOOD BY COT-
TON, CORN AND WHEAT.

The consumption of mineral _constituents by cotton, corn and

wheat has been calculated by Prof. E. W. Hilgard; the area pro-

ducing the crop is assumed as an acre in each case. The determina-

tion here given explains agricultural phenomena in connection with

the soils of northwestern Georgia.

O~<E BALE or COTTON. 1,350 Pounds of seed cotton: (400 pounds of lint) make
four pounds of ash containing ....... . ....... . .. . 950 pounds of seed .cotton make 41 pounds of ash,
containing . .. ...... .. ..... .. .... .. .. . ... . . .. .. .

Pbophorie Pota~b . Acid.
1.6 0.5 14.7 15.2

Total in seed cotton . . . . . . ......... . . .. .... . ... . . . . lli.3 15.7 Of the 41 pounds of the ash in the seed: The hulls, weighing 475 pounds, containing 9.5 pounds
of ash. The oil cake, weighing 368 pounds, containing 31.0 pounds
of ash. The oil weighing ... . 107 pounds, containing 0.5 pounds
of ash.

950

41.0

FIFTEEN B USHELS OF WHEAT.

The grain makes 18 pounds of ash ....... .. .... . . . . .

;),5

9.0

Two tons of straw make 200 pounds of ash (silica

128 pounds ), containing . . . . . ... .. . . .. . .. . . . . ... . . 8.0 3 .0

Total. .. ... . .... . ..... .. . ... . . . .. . . ... .. .. ... . . ... 13 5 12.0

THIRTY-FIVE B U8HEI. 8 OF CORS .

The grain makes 25 pounds of ash, containing .. ..... . . . . 6.0 13.0

Two tons of stalks, etc., make 200 pounds of ash (50

pounds of silica), containing . . ... .... .. . . .... ... .
-

-15-0 -

16.0
--

Total . . . ... . . . ...... . ....... . ..... . . . ...... ... .. . 21 0 29.(}

From these tables the following conclusion is drawn: if

nothing be returned to the soil-

A bale of cotton (seed and lint) withdraws ... . .. . .. . 16.3 15.7

Fifteen bushels of wheat (grain and straw) with-

draw . . .... . . ... . .. . . . . .. .. ' ... . ... .... . 13. 5 12 . 0

Thirty five bushels of corn (grain and stalk) with-

draw . . . . . .. . . . ...... . .... .. .... . . .. ...... . .. .. . 21.0 29 . 0

328

ECONOMIC RESOURCES.

I the cotton seed, wheat straw, and cornstalks be returned, then there is permanently withdrawn:
The cotton lint (of one bale), containing............ The wheat (grain of 15 bushels), containing....... The corn (grain of 35 bushels), containing..... . .. .

1.6 0.5 5.5 9.0 6.00 13.0

This chapter is not intended as a treatise on agricultural geology, nor will time permit of a full consideration of the subject, which may be found in the reports of Johnson, Hilgard, Smith and many -others; but this epitome will make the report on the soils of Northwestern Georgia more intelligible.

S01LS.

32!!

CHAPTER XLIII.
GEOLOGICAL AND CHEMICAL RELATIONSHIP OF THE SOILS OF THE PALEOZOIC FORMATIONS.
CONTENTS.
Sons OF THE OosTANAULA SERIES: Analyses. SoiLS OF THE KNox SEnn1s: Red Soils; Gray Soils; Analyses. SOILS OF THE CHICKAMAUGA SERIES: Analyses. SOILS OF THE l'tED MOUNTA IN SliRIES: Analyses. SoiLS OF THE Sun-UARBONIFEn'ous S};Rn:s: .Fort Payne Chert; Floyd Shules;
Mountain Limestone; Anrrlyses. SOILS OF THE COAL MEASURES. 1,AFAYETTE AND ALLUVIAL SoiLS. <GENERAL NoTES ON COMPOSITION AND PHYSICAL PROPERTIES OF SOIL.
SOIL~ OF THE OOSTANAULA l:iERIES WITH ANALYSES.
Note.-In all cases not specified the samples of soils taken for unalyses were from the edges of fields or roadsides, so as to ascertain the value of original soile rather than those of variable degrees of exhaustion or of fertilization.
COOSA VALLEY PHAS"E.
Distribution.-Tbis phase is confined to the Coosa valley, southwest of Rome, and a belt along the Oostanaula river extending into whitfield county (see map). This is the Cambrian phase of what is popularly known as the "flatwoods." It is characterized by more or less level tracts with local undulations. The drainage -is often defective and soil thin. This is derived from arenaceous shale, which in places is highly calcareous. The southern end of the belt i~ generallr nncultivated and often covered with large short-leaf pine, post-oak, some black-jack and other oaks. ItH northern extension is characterized by many low ridges, anrl the soils resemble those of the oyerlying Oost.anaula series.

ECONO}llC RESOURCES.

The soil is greenish-yellow, or dark, ot sometimes red (especially towards the northern end). Below the surface the yellowish color is, apparent. It is highly siliceons, and the microscope shows some grains of sand Ti--5 of an inch in diameter, but the great proportion is less than ofr 0 of an inch in diameter; so that the character of ibe sand favors the retention of water, which often accumulates upon its smface. There are several beds of impure limestone crossing the formation, as at Thomas' mills, and in ~uch localities the soil is better t.ban in the more shaly belts.
The sample of drab soil for analysis was taken from two miles east of Coosaville, along the river road, at an e]eyation of more than 150 feet above the river. Here the land was productive.

Arwly8is No. 1.

Lime (total)..

---- -- - --------- __ _

3.029

Magnesia - --~-- - -- -~----- .. -_ ----- _

0.965

Potash (total) , __ . _ . . ___ _ ____ . __ _. _ . _ .. ___ .. _ 0.624

Soda ___ ,__ _ _________________ _

1.115

Sulphuric acid . ____ __

0.:329

Phosphoric acid (total) _ Ferric oxide Silica __ , _

. 0.416
----- - ~ 4.621
67.245

~<\..lumina ___ __ __ __ ___ ----.--- ____ .. ------- _

7.215

Water ___ ___ _ ------------Organic matter___ _ ___ ____ _

--- ----- -- _

3.715 9.762

Undetermined, loss, etc. _______ _

0.964

100.000

Lime(solubleinacid) .. ------- ---- -- - ____ __ _____ __ 2.274

Potash(solnbleinacid)-- -- ---- ------------ ----

0 .376

Phosphoric acid (soluble in a0id) __ _ _ _ . __--. _ 0. 262

The locality of this soil is near the margin of the formation,. and is apparently the more fertile part of the belt. The same char-

SOILS.

33ll

acter is noted north of Rome, as in Gordon and Whitfield counties where the belt in more generally cultivated than southwest of" Rome.
The analysis indicates fertility. But portions of this formation are characterized by stiff, cold soils, whir,h fa,ot the reduction of the iron to the condition of ferrous oxide, which is an objectionable condition. There is considerable variation in the soils, whether in the vicinity of the more calcareous or the more siliceous members of the Coo&;t series, as shown in comparing the above analysis with one made by Mr. J. M. McCandless from a sample taken at Bell's ferry on the Oostanaula river above Rome:

Analysis No. 2.

Lime (total) ___ . ---- _______ _ - .. ____ --- ____ _

Magnesia ___ __ ---.------. --- -~- ---- Potash (total) ---- . __ .. _______ , __ _., ____ _

Soda _ _ _ . _ __ __ _ __ ..

Sulphuric ac~8 __ .. _______ .

P\.hosphoric acid (total) ____ __ ______ .... _

Ferric oxide

_ __ __ _____ _ . _ - ..

Silica____ _

_ __ __ --- _

Alumina . ______ _ . _ . _ ____ __. ___.

Water (hygroscopic) __ _ _. .. . __ _.. _..

Water combined and organic matter Loss ___ - -- ___ ----- _ _ ________ _

0 . 24~:
0.691 .
1.42~
0.689 0.033: 0.112 4.451 77.189 9.429 1.110 4.060 0.560

100.000

Lime (soluble in acid)_ . __ . __ . __ _ ___ ______ _

0.125

Potash (soluble acid) __ _______ _____ ___

0 .4 24

Phosphoric acid (soluble in acid) ___ _ . __ _______ ___ .. 0.077

Under culLivation and drainage the lands ought to be improved.
On approaching the State line the features are similar to those or

ECONO!IUG RESOURCES.

Alabama, where the State survey finds plant food also present, with .the physical conditions unfavorable, and with a deficiency of phosphoric acid iu places.

CONNASAUGA VALLEY PHASE,

The soils of this geological series cover only a narrow zone in
the western part of Polk and Floyd counties. In Bartow, the
eastern and central portions are occupied by different belts. Half
. -of Gordon, Murray and Whitfield counties are covered by tbe same
series; narrow fertile belts cross Chattooga, Walker and Catoosa counties. The series presents three phases :

(a) Adjacent to the Oostanaula fault there is a chain of erested

ridges composed of shales with some thin sandstones (the Knox ~";::tndstoue of Safford, or the Rome sandstone of Hayes). The soil is in part, light colored throughout the rugged portion of the belt, but often red in the depressions between the interrupted ridges, and in the valley west of Taylor's ridge.

On the Georgia-Alabama line a sample of the soil was taken from the roadside. It is a stiff, bard, compact, yello~!sh grey soil, composed of very fine round grain~; of quartz, coated with earthy matter in a matrix of clayey and angular siliceous partieles. Tlie physical conditions of the soil are unfavorable for agriculture; but .::;nfficieut plant food is present as shown by analysis.

Analysis No. 3.

Lime (total)_ _ _ _ _

1.321

Magnesia .. ----- - _ . _ . ---- - - -

0.752

Potash (total)._ ... _ ___ __ _ _ .. -- _ _ _____ _ 0.315

So da _____ _ ___ __ _ __ __ _ . -- ---

___ -------- 0.162

Sui ph uric acid _ __ _ ___ _ ___ _ ___ __ ____ _ . _ ___ 0.085

r:hus.phor~c acid (total) - ---- _____ _ ____________ .- -- -- 0.312 :Berri e oxtde .. ______ .. ____ ... __ _ _ .. ___ -- 3 .654

S ili ca Alumina ____ ___ _

77.993 6.720

Watet ___ --

2.421

Organic matter ___ . - - __ _ .. __

5.404

Undetermined, loss, etc __- _ __ _

0.861

100.000

SOILS.

Lime (soluble in acid)--__ - - ---- - - - - - -- --- - - _ - 1.068Potash (soluble in acid)_ ___ _ _____ __ __ _, _ ___ __ ,____ _ 0.161
Phosphoric acid (soluble in acid) __. . _ ----- -- __ _ ___ 0.183-

Another sample of soil from the same horizon as the last in the lower members of the Cam brian shales near Ringgold yielded the following analysis (Mr. McCandless) :

Analysi8 No. 4.

Lime (total) ---- -----. _ -- - --- - - - - -- ---- - J\IIagnesia. __ - - - - _ -- ------- ____ _

Potash (total) ____ --

- - ---- __ .. _

Soda

__ . _ _ _. __ _ . . ~ ______ ___ . . _. _ _

Sulphuric acid __

__ . _. .

Phosphoric acid (total) ____ _ ___ _ ___ _

Ferric oxide_:.____ Silica___. _

- - ----- ___ _

Alumina ______ - -- - - - ---- --- ------- ----- Water (hygroscopic) ___________ _ __ __ . _

water combined and organic matter __ _ _ ___ .

L oss

-- --

0.220 0.482 0.579 0.314 0.03;.1. 0.143 3.38.5 84.181 7.075 0.334 3.156 0.098

100 .0 0 0

Lime (soluble in acid) __ . __ _ _ _. _ .. _. _ Potash (soluble in acid) _-____ . . --- - ____ Phosphoric acid (soluble in acid) _ __ . _

O.ll G 0.:377 0 .052

This sample is much more siliceous than that further sonth, and also much poorer in lime and phosphoric acid, although richer in potash.
The area of this soil, however, is small, as it forms only a narrow belt, but in Gordon aml 'Vhitfielrl counties, it approximates in. character to red shale lands, and is covered with the same timbe1.
(b) The shales have had their calcareous matter leached out, leaving silieeous splinters, in the form of ~reat beds of shingle-

:3M

ECO NO~IIC RESOl!RCE S .

.covered with only a thin soil and often almost bare. The color is brown, red, greenish and gray. The shales form ridges in the ,greater valleys, which are often well wooded. To some extent, these .ridges border the valleys of section (c), but are most largely developed in eastern Bartow, Gorden and parts of Murray and Whitfield .counties, where the belts are many miles in width. These hilly shale lands are not very extensively settle~, as the soil, :although fairly producti \'e, is subject to drought. The shales are wooded with pines, red, spanish and white oak, hickory and chest.nut, with occasionally black-jaclc
(c) Other pottions of the shale series are more calcareous with beds of limeHtone often in thin seams. These limesto~1e:;; appear in 'lllost of the valleys, and the shales weather into clays from five to fifteen feet deep; resembling the residual clays of the Knox series. 'These soils are of red color and amongst the best in the state. They form the valley, two or three miles wide, extending from .Etna to Cave Spring, Home and to Calhoun; also other narrow valleys in Whitfield, Catoosa, Walker and Chattooga counties. A small anticlinal valley of these soils occurs at Woodland; another belt extends from Kingston to Adairsville and Calhonn. Eastward valleys of the shales of both sectiom (b) and (e) occur in the broad belt extending through northeastern Bartow, acror<s Gordon, and .occupying most of southern Murray and Whitfield, and narrower bc'!ts further north. On both the eastern and western sides of this broad belt soils of section (c) occur, as also in the principal valleys .of th1s zone, which is shown on the map. Thus about Cassville, there is a good farming section aI'd also to the north ward. This is equally the case at the foot of the mountains forming the westem borders of the metamorphic zone.
As the soils of the shale zones often border those of the succeeding Knox dolomite series, which they elosely resemble, the line of demarcation is not alwavs -well defined, and indercl, is agricnltur:ally unimportant.

SOILS.

335

A type of the soil is seen in the analysis from a field of Mr. :Hugh Montgomery, at Cunningham Station. There the soil was a ..(llayey loam overlying the splintery shale. Its color is red, of medium tint. It is composed of free quartz grains, hardly rounded
,{rto of an inch in diameter and smaller), embedded in an earthy
matrix.

Analysis Ko. 5.

,Lime (total)---- ___ _ - - --- - - - ____ -- - ____ - -- -- 3.250

Magnesia ________, ___ - - - - ____ ------ -- ---- 1.060

Potash (total)_ ._,_ _ ___

_ --- _ __ _ 0.326

.Soda __ _ ___ ____ _ -- - - ---- -----

___ ___ _

0.218

.Sulphuric acid ...___ . _____ -=--- ----- - ___ _ 0.214

Phosphoric acid (total) __ .. _ .

.. L

_

_ _____ _

0'.152

Ferric oxide _____ __ - - - ----- - - -----:--- __ 3.212

.Silica ____ --- _ - - -- -- - .. --- _

68.427

Alumina.. _

5.873

Water. ___ _

3.106

Organic matteL ___ ___ _ . ___ . _________ .... _

12.486

Undetermined loss, etc . _ _ .. ____

0.762

100.000

Lime(solubleinacid) __ --- - _ --. _ -- - ----- 2.736

Potash (soluble in acid) _ ---- - - - - ------------ -- 0.204

Phosphoric acid (soluble in acid) __

__ - __ _ 0.114

The soil is decidedly arenaceous and more loamy than clayey. It contains a large supply of plant food in an ayailable form. The fiel'd was covered by an excellent crop of corn when seen.
Another analysis of 100i I (by Mr. McCandlesl:l) from the same formation at SummeniHe is here giYen. It shows this western belt as much more siliceous than that from which sample 5 was taken. It is also richer in potash, but poorer in phosphoric acid :and lime.

336

ECONOMIC RESOURCES.

Analysis No. 6.

Lime (total) -

. _ _ ----

- - ----- 0.295-

Magnesia -- - -- - - - -- - - - . - - - - --- - -- ---- - - - - 0.6llj Potash (total) _ __ . . ___ . __ __ _ . _. __ - __ ___ _. ____ __ . 0.521

Soda _ --- -- .

- - -- ----- ---- - - - __ - - - - --- 0.833-

Sulphuric acid ____ __ ___ _________ "--- - -- _____ _ --- 0.081

Phosphoricacid(t.otal) - -- . ------ - -- - - --- - ---- 0.833 Ferric oxide . ____ .__ _ ___ __ - ____ . ____ . ___ _ 3.403
Silicl1 _ .. _. __ _. __ __ ____ . . __ __ . _. ___ . _ ___ . 78.230

Alumina_ ___ ___

---- --- - ----- - 9.277

Water (hygroscopic) . __ _ __ . . . __ .. _ .. __ __ _ . 0.695

Water combin~d and organic matter_ . _________ . _ __ _ 5.765

Loss __ . . .

_. . ___ . _. ___ 0.148

100.000

Lime(solnbleinf!.cid). -- -- --- ______ _ __

0.1.51

Potash (soluble in acid) ----- - - __ ------

_____ . 0.5.14

Phosphoric acid (soluble in acid) _ ... . __ . _ . __ ___ ____ __ __ 0.075

From Mr. Haskin's farm, a mile north of Ca,e Spring, a sample of dark red soil was taken alongside of a valley which was bounded upon the eastern side by Knox dolomite ridges. The soil appeared to have been derived not only from the shale, but seems to have crept down the hillsides by washes, on account of its strnctUI'e, and also of its aluminous or clayey character. It possesses high fertility. Its composition is seen in Analysis No. 7.

SOILS.

33'T.

Analysis No. 7.
Lime (total)- - - - - ___ ___ . __ ---------------- - __ _ 3.561' Magnesia ----- - ____ --- - -- - --- ___ _ ______ ___ 0.93<2: Potash (total)- ______________________________________ 0.654 Soda _________ -- ----- _------------- _-- ----- _____ _ 0.420 Sulphuric (acid) ________ _ _______________ ----- ___ _ 0.212: Phosphoric acid (total) - __________ . ____ _--- --.- ___ _ 0.136. Ferric oxide _________________ . ___ ______________ __ ___ _ 3.862: Silica _______ ___________ ------ ____ __ _______ __ __ .. _ 60.084 Alumina ______________ ___ _______ __________________ 15.691
Water ________________ --------- - - __ ____ __ __ _ __ __ _ __ 4.320
Organic matter ______ .. - ..- . .. __________ - , __ _____ ____ __ _ 3.104
Undetermined, loss, etc_ -- -- ------------------------ _ 0.536

100.000
Lime (soluble in acid) ---------------------- ------ 3.028 Potash (soluble in acid) --- --------- --- -- ---------- 0.419 Phosphoric acid (soluble in acid) _____ - - --- ------- __ 0.094
Many of the shales of the Oostanaula series are calcareous. The limestones of the Knox series are aluminous and sandy. In the weathering of the latter, the removal of the calcareous and magnesian matter leaves a residual clay not very different from that derived. from the calcareous shales.
SOILS OF THE KNOX SERIES.
RED SOILS.
These soils form most of the lands of Polk, eastern Floyd,. south and >yel!t Bartow, central Gordon, and elongated basins in Murray, W:hitfield, Catoosa, Chattooga, Walker and Dade counties. The lower beds of the geological formation give rise to fertile red lands, whilst the higher and more siliceous members originate gray> cherty ridges and undulating gray plains.
(22)

.

'338

ECONOMIC RESOURCE!'~.

These two groups of Knox soils are very strongly marked. The ,first consists primarily of red loamy lands, from yellowish to deep rorange red loaq1s and heavier underlying clays. The surface is :sometimes more sandy and of light color, where a portion of the 1red clayey matter has been washed out. When of deep color, 'granules of brown ore or limonite are scattered through the soil. 'These soils are usually stoneless, or in occasional localities contain chert, as on some red ridges and hillsides.
'These lands, together with the shale valley lands just described, form the best soils of northwestern Georgia, which are amongst the best in the State. They are commonly adjacent to the shales of the valleys, but, again, the erosion has not removed them to depths :sufficient to expose the shales, as in the valley of Cedar creek, in Polk county, or along the broad red belt from Fit:>h creek extending 'into southeast Floyd and onward to the Etowah river in Bartow county. In the large valleys, and adjacent to the neighboring formations, shown on the map, such lands prevail.
Again the red lauds appear upon the margin of the series south :and near Dalton. The red lands prevail on the ridges and in the valleys of the so nth and central portions of Knox belt in M turay County.
East, near Varnell, the red Chickamauga lands resemble the red Knox soils. On portions of Missionary ridge and other ridges west of Taylor's ridge limited areas of the Knox soils are red, hut the gt'ay generally prevail.
Red alluvial deposits ocour on some of the hills in the river regions to an elevation of from 80 to 150 feet, which is liable to be mi~:~take n for residual red soils derived from the dolomite series. These have a character of their own, and when they contain rounded gravel they al'e readily identified; but without gravel they a1e liable to misidentification. Such deposits are on hills within from one to three miles of the rivers.
The red so.ils are widespl'ead on subordinate ridges, adjacent to

SOILS.

339

!the valleys where they occur. On the summits of some of the

.higher crested gray ridges they also occasionally occur, in which ~ase they are more stony than in the valleys. The red ferruginous

ridges are often poor in phosphoric acid and humus. In the valleys

the available acid may be sufficient. Only this one mineral element

of fertility is necessary to be added where the soils have been ex-

;amined. But on the iron ore bearing knobs the red soil is deficient .in organic matter as well as in phosphoric acid.

The following analyses were taken as types. No. 8 is soil from ~the farm of Dr. W. I. Benham, situated in a broad valley about

four miles west of Cartersville. It is deep red loam and composed -Df very small earthy granules and free quartz. It is highly fertile.

_No. 9 is a deep red soil on an ore bank four miles southwest of
KingRton. It is composed of rounded grains of quartz (-lo to Th
--of an inch in diameter), coated by a large amount of clay. It is

-very deficient in available phosphoric acid and organic matter, but

-contains a fair share of unavailable acid.
No. 10 is from the surface of an ore bank southwest of Cedar-
town. It is composed of rounded grains (1 h of an inch) of quartz
:in much clayey matter. It is very deficient in phosphoric acid and

Drganic matter. In both No. 9 and No. 10 the ferric oxide is in ,great excess, the clayey matter is in abundance, and the soil is

sti.ffer than usually seen on Knox soi-ls.

Analysis Nos. 8-10.
No.8. Lime (total) . . . . . . . . . . . . . . .. .. .. . .. . .. . .. .. .. . . 6. 708 Magnesia........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.214 Potash (total) .. .. .. .. .. . .. .. . .. . .. .. . .. .. .. .. .. il.821 Soda.............. . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . 1.732 .Sulphuric acid ........ ....... .. . .......... .. .. . 0.114 Phosphoric acid (total) . . .. . . . .. .. .. .. .. .. .. .. .. . 0.321 'Ferric oxide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3. 750 1-ilica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 .135 Alumina .............. . .... ... ,,.... . . . . . . . . . . . 6.110 Water. . . . . . . . . . . . . . . . . . . . . . .... . .. . .. . , . . . . . . . 3. 720 Jrganic matt;e.. . .... .. . .. .. .. . .. .. .. . . .. .. .. . .. 4.654
l nO.aterm ilJed, losa_; etc. , . ... . . . . . . . . . . . . . . . . . . . . . 0. 731

No.9.
3.111 1.021
tl 671 1.101 0.420
0.063 10.356 64.500 12.680
4.310 1.204
0.563

No. 10. 3.040
0.876 0.462 0.112
0.238 0.042
10.2Ul 66.61!'! 12.340
3.600 2.104
0.354

100.000 100.000 100.000

340

ECONOMIC RESOURCES.

Lime (soluble in acid) ................ . . .. . ... .. . 5 . 619 Potash (soluble in acid). . . . . . . . . . . . . . . . . . . . . . . . . 0. 509 Phosphoric acid (soluble in acid) . ............. .. . 0.242

2.570 0.408 0 . 044

2 .493' 0.27Z 0.030

In the value of the red valley lands, derived from the shales or the dolomites, the variation is not so great as between them and the red ridges, some of which, however, are rich, but generally poorer in phosphoric acid and humus than at lower levels, The ore,bearing ridges are, agriculturally, the poorest of the red lauds.
The growth of timber is red, black, post and spanish oaks, hickory and dogwood; and some short-leafed pines, black-jacks, etc., on the poorer ridges; also some walnut, chestnut, gums, etc., on the lower lands.
GRAY SOILS.

These are derived from the siliceous members of the upper Knox dolomite series. The surface usually is covered with chert, left upon the solution of the calcareous matter, on or in the gray soil. Beneath the subsoil may be yellowish or reddish. where the chert is abundant the soil is often almost sterile. Upon the western side of the Knox belt the gray lands occur mostly upon ridges of a broken character, some of which are surmounted with a red soil upon their summits, that are sometimes stony. The intervening valleys are often narrow, bnt many contain fertile soils. These ridges have been protected from erosion by the cherty gravel covering, which, however, is more or less superficial.
The eastern side of the Knox belt, in Polk and Bartow counties is characterized by more gentle, undulating country, with less cherty gravel, and indeed, it is often entirely free from it.
In pr?ceeding northward, this characteristic increa,'!Cs in importance, so that in northern Bartow and acroBs Gordon county, the gray lands are mostly stoneless (except ridges upon their western border). This undulating character prevails on various belts in Catoosa, whitfield, Chattooga, Walker and Dade counties, but with interrupted ridges and valleys. In these counties the gray

SOILS.

341

laud is seen in valleys as well as ou sides and tops of the ridges. There are many lime sinks scattered over the formation. The rolling lands are sandy loams, with ofoon little or no cherty gravel, :and with a yellowish subsoil, with sometimes the character intermediate between the red and the cherty gray lands. The soil is often of very fair quality (as sbown in analysis No. 11).
The composition of some types of the soils may be seen from the analyses. No. 11 is from near Seney. It is gravelly land with little depth of soil. It is composed of particles of semi-glossy
-earth, and some rounded quartz grains (2 -h- to 2 h- of an inch in
(liameter ). It is very siliceous soil with a small amount of iron. It is badly deficient in phosphoric acid and low in humus.
No. 12 is a sample of gray soil two miles south of Cedar creek, in north Bartow. It is composed of a glossy matrix, the particles
of which are less than olu of an inch in diameter, in which there
are rounded quartz grains 2 1J-0 of an inch. Here the available potash is low and the phosphoric acid very deficient.
On the farm of Mr. Osbnrne Shaw, three miles north of vVooley's ferry, No. 13, is a drab, gray, mellow siliceous soil composed of rounded grains of quartz (-lo of an inch in diameter) loosely embedded in a small amount of earthy matter. This gray land is on the :mmmit of a rolling country and produces good crops. The analysis shows a soil with more than sufficient available min-eral food, but the humus is not abundant; still the crops are good.
No. 14 is a dark gray soil near ~Wooley's ferry. It is composed of crystalline particles in an opaque matrix composed of very small
grains. It also contains so1ne rounded particles of quartz ( rh
of an inch in diameter), This soil is not stony. It is low in available lime ; deficient in available potash, and very poor iu phosphoric acid. Tbe quantity of iron is large, and the objentionable condition of ferrous oxide favoring the light color prevails.
No. 15 is a gray soil (analyzed by Mr. McCandless) just west .of Taylor's ridge, on the road from Lafayette to Greenbush. There

342

BCONOMIC RESOURCES.

is considerable variation in all of the soils of the same formatiow:: between those situated east and west of Taylor's ridge.
Analyses Nos. 11-15.

No . 11. Lime (total) .... .. ... . . . . ... _ 1.240 Magnesia ....... . ....... ....... . 0. 092 Potash (total) .......... ...... . . 0 .262 Soda .... . . . .... .. ...... ....... . 0 .314 Sulphuric acid . . ........ .. . .... . 0 .092 Phosphoric acid (total) ........ . 0 .01.') Ferric oxide .... . .... . . . .... ... 2 .962 Silica . ... .... . ........ . ..... .. 82 .018 Alumina . ............ . . ...... . . 5 .352 Water . . . .. . ... . ...... . .. . ..... . 3. 115 Organic matter.. . .. . .... .... .. . 3.675 Undetermined, loss, etc .. . . . . 0 .863

No. 12. 1. 62.'5 0.732 0.156 0.210 0.096 0.034 3-212 79.326 6.821 2.312 5.111 0.365

No. 13. 2. 964 1.213 0.436 0.287 0.183 0.240 3 .231 79.039 4.794 2.648 4.113 0.872

No. 14-. 1.04-2 0 .021 0 .092 0 .064 0.0140 .028 10 .350 84 .781 4.222 2.606 3 561 0.354

No. 150 .16(} 0.133 0.54& 0 . 359 0.056 0.071 2.306 86.435 5.224 0 . 7663.5340 .41(}

100.00Q 100.000 100 .000 100.000 100 .000

Lime (soluble in acid) . . .

0. 943

Potash (soluble in acid) ......... 6 .H1

Phosphoric acid (soluble in acid) 0 .008

0. 304 0.072 0.019

2 . 611 0.251 0 .171

0. 769 0 .043 0.018

0. 089 O.HJ7 0 .041

From the analyses a great variation in the value of the gray laud may be seen; yet it is thought by many to be better than red land for cotton (with use of commercial fertilizers), as the bollsdevelop well upon a smaller growth of the weed.

These lands are warm, and, in wet seasons favor the growth of cotton lint which consumes very little mineral food; still much of this gray land, especially the more rugged, is not cultiyated, whilst the less stony in Gordon county is largely under cultivation.

THE SOILS OF THE CHJCICAMADGA SERIES.
These soils vary from red to bluish clays. When derived from the limestone they are confined to narrow belts from Cedartown southward,:in the Fish creek district and also in the Rockmart district. They also occupy many long basins in Murray~ Whitfield, Catoosa, Chattooga, Walker and Dade counties. They often border and join the soils of the Knox series and have similar character-

SOILS,

343~

istics to the red soils, but form heavier clay soils. They form some of the best soils in Georgia. During wet seasons the roads across them are the muddiest in the State.
The shales or slates from which some of the soils are derived, are. closely connected with the limestone members of the series. The more shaly beds occur principally in Polk county; and although they occupy those elongated belts in the northwest counties, as shown upon the map, the separation from the limestone soils are less marked.
These soils are grayish or sometimes reddish and shallow, when the splintery slates come near the surface. When they have disintegrated into mellow land, the soils are loamy. The better soil contains an abundance of lime and potash, with sufficient phosphoric acid to produce fair crops, but rather low in availability. Analysis No. 16 is a sample from a mile east of Berry in Polk county. It is thin and of dark gray color, and mostly made up of subangular
grains of quartz (2i0 of :m inch in diameter) in a small amount of
earthy matrix. No. 17 is of the sam!:J kind of soil as No. 16. It lies on a low ridge, one and a half miles east of Cohutta station in Whitfield county, and occurs immediately above disintegrated shale. Soils in Murray and 'Whitfield counties are derived from beds more calcareou&J than in Polk county. It is composed of vitreous parti-
cles and rounded grains (rlo to ofro of an inch and less in diam-
eter) in opaque earthy matrix. The soils in both cases are fairly productive, but need more or less phosphoric acid. In the former
in sample, the organic matter is rather low; the latter, it is large
and the land more productive.

:344

ECONOMIC RESOURCES.

Analyses Nos. 16 and 17.

No. 16. Lime (total)---- -- _________ _ _ . ___ __ 2.643

, Magnesia ____ __ __ --- ------- ------- --
Potash (total) - - ---- .. -- - ---- - - - -- . Soda ___ ___ __ _____ _ ___--- - --- -----Sulphuric acid ___ _ ____ ___ ____________ _
Phosphoric acid (total) -- -- -- ___ ____ _ Ferric oxide _____ ___ ______________ ____ .

1.106 0.520 0.231 0.164 0.067 4.204

:Silica _____ ___ -- -- --- - ----- - ---Alumina .. - - - - -- -- --- -- - - --- ---Water ______ __ ______________ _

77. 826 4.252 3.516

Organic matter --- --- - ----- - .. - - -- - 4.710 Undetermined, loss, etc. ___ ______ ___ ___ 0.761

No. 17 '1.536 0.648 0.243 0.108 0.193 0.104 4.126 74.723 4.762 2.455 10.623 0.743

100.000

Lime (soluble in acid) _____ ___ --- ___ _ Potash (soluble in acid) -- - -- - - -- ___ _ Phosphoric acid (soluble in acid) -- - - - ---

2.209 0.311 0.049

100.000
1.307 0.132 0.058

SOILS OF RED MOUNTAIN SERIES.
Soils of this formation occur only on the ridges as shown on the geological map. The soils are somewhat similar in productiveness to those of the red variety of the Knox series, but with the lime very much leached out, as would be expected from their occurrence on the hillsides. The laud is sometimes shingly. A type of these .soils of deep red color is seen in an analysis (by Mr. McCandless) '0f a sample from the eastern side of Taylor's ridge on the LafayetteGreenbush road.

SOILS.

345

Analysis No. 18.

Lime (total) _ -- - -- ------ -- __ _ --------

0.078

Magnesia, ______ .... ______ .. _. __ - . _. _________________ _ 0.128

Potash (total) ---- - -- --- - -- ------- -- ---- --- 0.46.1

Soda --------------- - --------- - ---------- 0.321

Sulphuricacid __ ------ - -- ---- - -- -- - ---------- 0.073

Phosphoric auid (total) . ... __ ---- ---- -----.------ -- _ 0.135

Ferric oxide ------ ------------------------- ---- 6.655

:Silica __ - ----- -- - .. ---- -- --- - -------- __ . _ 73.304 .A lumin a. ____ ------ __. -- _ ____ . ___ __ ____ _ 12.305

Water (hygroscopic) __ ______ - - - --------------- ___ _ i.858

Organic matter and combined water_ . _------- -- _ ___ _ 4.542

Loss ---- ---- -- ------ --. ------------- -- 0.138

100.000
Lime(soluble in acid) - -- --- --------- - ---- ---- 0.032 Potash (soluble in acid)- . _______ __ .. ------ ______ ______ 0.298 Phosphoric acid (soluble in acid) __ ___ . __ - . - _.... __ 0.096
SUB-CARBONIFEROUS SERIES.
The Fo1't Payne chert forms a poor stony soil which is mostly confined to the ridges that are shown upon the map or bordering the other Sub-Carboniferous series in belts too narrow to be shown upon the map. These stony belts are unimportant.
The Floyd shales constitute a considerable portion of the "flatwoods" of the lo,ver basins and are poor lauds and ill drained. This deficiency does not rise entirely from the absence of plant -food, although the phosphoric acid is often low. The region is often uncultivated. Amongst these .shales there are various calcareous .beds. This formation extends up into the west Armuchee valley where a sample of soil was analyzed by Mr. McCandless:

346

ECONOl\UC RESOURCES.

Analysis No. 19.

Lime (total) -------------- --- - ___ _ ------Magnesia ._ ____ ____ __ _ - - -------------- ---~otH.sh (total) . --------- - - __ _____ ____ ---- oda _____ . ___ __ ___ . __ ____ .. __ . _ _ __ . __ . . .
Sulphurir, acid. ____ __ _. __ _ ___________________ ___

0.158' 0.2230.508 0.315 0.089

.Phosphoricnoil (total) -- - -- -- --------- --- - - - -- 0.085
F l'ri ox:ide_____ ---------- ----------- ______ .. 2.541
Silica _ __ __ ___ _. __ .. __ .__ ____ . ___ . __ ___ _ 87.092 Alumina ____ ________ ____ --- - - - --- - - -- -- - - -- ---- ~ -- 4.099 Water (hygroscopic) _ __ _ __ _ ___________ . __ 0.689

Organic matter and combined water --- -------- - 3.561

Loss___ ___ __ __________ _ _

0.640

100 .000

Lim o( Juble .inncicl) _ ___ __ _ __ ___ ___ _ ____ _

0.082

P )tlt"i (flulu l .le i.n n id) ---- _ __ ___ ... ___ _____ _____ _ 0.236

Ph pb uri a id (so luble in acid) --------- - --- ----- - 0.0.'51

Mountain limestones upon the sides of the Coal Measure plateaus

and in parallel valleys give rise to drab clay lands, which contain

sufficient plant food, but often most deficient in lime which has

been leached out. A sample, analyzed by Mr. McCandless, was

taken from the land at the head of MclJamore's cove :

Analysis No. :!20. Lime (total. _____ .. ______ _______ ____ _ ___ --- -

0.143

:Mug ne ia _ -------- - -------------- ----- - .-- _
Potash(total) _ .. --------- -------- --- - -- --Soda____ __ __ ---- - - - - - ---- -. _ ------- _ _ Sulphuricacid _________ ___ ___ _ ___ ____ ________ . --

0.778
0. 99 6 0.270 0.022

Phosphoric acid (total) . .' _______ --- - - - --- - ----- - 0.121

Ferric oxide - ------ -- ---- - -------- - - --------_ 2.991 Silica.. ___ . _________ __ _. __ . _ . ____ __ ____ ______ __ ____ 77.1 95 Alumina .. _____ ___ _____ __ ___________________ _________ 10.249

Water (hygroscopic) --- -_ - -. __ ------- ---- - 1.812 Organic matter and combined water. ... __ . _. _. __ _ 4.998

Loss. --

_ _ ___

-------- 0.425

100.000'

SOILS.

347

Lime (soiuble in acid) .. . ___ _ _. ___ ____ ________ . ___ _

0.071

Potash (soluble in acid) ______ _____ ____ __ ______ , ___ _ 0.413-

Phosphoric acid (soluble in acid) _ ____ __ - - ------ --- _ 0.058-

SOILS OF THE COAL MEAST:RES.



These give rise to light sands of variable compositions, which

are very ~oor in phosphoric acid and lime, as shown from the

analysis (Mr. McCandless) of a sample from the top of Saud

mountain. This soil also occurs on Lookout mountain :

Analysis No. f21.

Lime (total) ____ ___-- --- - ----- ___ ___ __ -----Magnesia ______ _. . ___. ___ ___ ___ .. __ . _ ._ . _____ ___
Potash (total) -- - --- - - ----------- -- - , __ ___ _ _ Soda _____ ------------------ ----- -------- ____ __

0.1150.244 0.541 0.355

Sulphuric acid - -- - - -- - ---- - -- -- -- --- --- ----- 0.053Pbosphoric acid (total)---- _____________ _ __ _. ____ _. 0.053
Ferric oxide . _. __ . ______ . . .. _____ . ____ . __. __ ______ 2.058 Silica __ __ ---- _____________ , ___ __ _ ___ 88.627

Alumina _ . ------ - - -- __ ____ __ . ----- - - _______

Water (hygroscopic) _ _ __

___ -- __

Organic matter and water combined _____ ___ .. - -- _ Loss___ __ _____ _ _.. __ _ _ ___ __ ____ _ _ _ _ _ .

4.412 0.405 2.9250.232

100.000

Lime (soluble in acid) --_

____ - ___ - -- _ 0.067

Potash (soluble in acid).- ___ - - ----- _____ ,_ - - -- - -- 0.201

r:hosphoric acid (soluble in acid) ____ ______ _ _

0.017

LAFAYETTE AJ:'D ALLUVIAL SOILS.
These soils are confined to hills and flats adjacent to the rivers, and seldom reach more than one or two miles from them.
The Lafayette deposits are red or dark brownloams, which occur
to at elevations up to from 80 150 feet above the principal rivers
and on eroded hills. These are genetically former alluvial deposits.

:348

ECONOMIC RESOURCES.

In many cases, they are recognized by containing rounded gravel at the base of the deposit; when the gravel is absent, it is liable to be mistaken for Knox red lands. Situated on the much-washed hills,
the phosphoric acid is apt to be more or less removed. There is also a deficiency of humus. The clayey matter is abundant, making a somewhat heavy soil. A sample was taken near Siilesboro, in Bartow county, and its character is seen in Analysis No.22. The color is deep red with an abundance of iron. It is composed of
free transparent rounded grains of quartz ( 2 -hr to oto of an inch in
diameter) as adhering to the earthy matrix.

. Analysis No. fJfJ.

Lime (total) ________ _______ ____ . ____ ________ __ ____ 1.674

Magnesia ______ _ _____ ___ ____ _ __________ __ _______ __ 0.120

Patash (total) ________----. _____ __ ___ ----- ____ _ 0.748

Soda _____________ ------- ----- -- --- ___ _ .-1.3

Snlphmic acid ____ ___ __ ___ ___ ____ ----- _

0.094

Phosphoric acid (total) --------------- ___ --- --- --- 0.082

Ferric oxide ----------------------- ----------- 12.214

Silica _ _____ ---- ______ _______ ___ . ----- _ 62.229

Alumina__ _______ ___ ____ __

___. __ ___ __ __ ______ _ 15.962

\:Vater _____ ____ ___ ____ - _____ - ___ . ________ __ __ 4.213

Organic matter_______ __ ... __ . _ __ __ __ ____ ___ _ 1.582

Undetermined, loss, etc ____ ____ ____________ -- 0.646

100.000 Lime (soluble in acid) ___ -- ____ . ___ -- -------- . 1.381 Potash(solubleinacid)---------- - -- - ---- -- _ ___ _ 0.3~2 Phosphoric acid (soluble in acid) ___ __._ __ --_ __ _ _.. . _ 0.043
The alluvial soils characterize broad flood plains of irregular outlines. These along the Coosa, Etowah, Oostanaula, Coosawatta and Connasauga rivers rise about 20 or 25 feet above mean low water. In width, they vary from one to one and a half miles, and are usually

SOILS.

349

fertile lands. Above the level, only occasionally indistinct remains of terraces are seen. The lowlands along the smaller streams are less defined, but the bottoms of the valleys are generally fertile.
Superficial sandy soil is occasionally met with on the slopes, arising from the washings of a portion of the clayey matter out of the soil, leaving a lighter soil, also of a lighter color than that from which it is derived. Approaching the greater rivers the surface of the red Lafayette deposit~ are thus connected with gray sandy lands.
GENERAL NOTES ON C0)1POSITION AND PHYSICAL PROPERTIES OF SOILS.
The availability of the plant food ~s based upon the easy solution of lime, potash and phosphoric acid. That which is insoluble cannot be regarded as plant food in the near future. In order to estimate this solubility, the samples were digested in cold dilute hydrochloric acid (ratio, one of acid to twenty of water) for thirty days. The lime is derived from earthy limestones and calcareous shales, and the soils now contain from 50 to 85 per cent. of it in the easily soluble condition. The samples being taken from practically virgin soil show a large percentage of lime in all cases. A great portion of this lime is ptobably in the form of easily decomposed silicates. The potash is also soluble to the extent of about 50 per cent., showing the highly decomposed state of the feldspar in the clay of the soil.
lVIore than 50 per cent of the phosphoric acid is soluble. In most cases, the magnesia is present in much smaller proportions tham the lime. The quantity of sulphuric acid is variable, bt7t' sufficient, being much depleted in the washed alluvial soil of the Lafayette series. The ferric oxide, in all but the red soils, falls below 5 per cent., except in No. 10, where it is over 10 per cent., and here it probably occurs to a large extent in the objectionable ferrous form. In the hilly red soils, the proportion of alumina rises sufficient to

ECONOMIC RESOURCES.
form more or less ~:;tiff clay. At the same time, the quantity of iron is usually high; hence, the silica is still further reduced in its ratio.
The organic matter varies, being less upon the hilly lands than in the valleys.
The flatwood soils often hold water, and are cut up into heavy, :rutted roads.
The ridges and higher lands of the Oostanaula series, owing to the splintery character of the siliceous shales, form dry. roads with no depth of mud. The valley red lands of the series, as also the red soils of the Knox series, form moderately muddy roads, but when dry, the ruts soon disappear, or the clay is siliceous and not very heavy and stiff.
The red lands of the Knox, the Chickamauga clays, and ~Lafayette series on the hillsides form the stiffest clay of northwestern Georgia.
The grey Knox and Fort Payne chert lands are siliceous and cherty, and therefore, not deeply muddy, except locally, where chert is in smaller quantities. The muds of the Maclurea series are particularly stiff and deep. The shales of the Rockmart series in Polk are similar to those of the splintery Oostanaula section; but, in Murray and 'Whitfield counties and west of Taylor's ridge they .approach more nearly to the richer shale and red Knox lands.

SOILS.
CHAPTER XLIV.
-GEOLOGICAL RELAT!I)NSHIP OF THE SOILS OF THE AGRICULTURAL EXPERIMEN'l' STATION OF GEORGIA AND OF THE COLLEGE FARM.
CONTENTS.
GEOLOGICAL CHARACTERISTICS OF THE V I CINITY OF THE STATION. ORIGIN OF THE SoiLS. STRUCTURE OF THE SOILS. TYPE OF THE SoiLS. CHARACTERISTICS AND Co~IPOSITION OF THE SOILS AT FARM . DEDU CTIONS FRml 0BSERYATIONS A ND A NALYSES. CoNCLUSIONs. THE RELATIONS OF PHYSICAL FEATURE!I. CONFORMATION OF THE RELATION OF PLANT GROWTH TO THE SoiL VALUE. SoiLS oF THE CoLLEGE FARM AT ATHENS.
GEOLOGICAL CHARAC'IlERISTICS OF THE VICINITY ,OF THE STATION.
The Georgia Experiment Station at Griffin is sitnated 011 a belt -of Arcluean or metamorphic rocks, which here forms a gentle undulating plain. The surface rocks are decayed, and only occasionally -do they appear at the surface. The characLer of the gneiss in this region is best seen in the railway cut between the farm and the neighboring railway station, where it is foliated and passes into a -qn6rtzose mica schist, that is, a rock with very little feldspar. It liei in beds dipping from 20 tv 25 S., 20 to 30 E. ThiR inclination gives some variety to the lands formed out of it, as d1fferent strata varying somewhat in character are successively brought to the surface in passing ftom southwest toward the opposite direc~tion. The dip is favorable to the decay of the rocks.
About half a mile from the farm toward the southeast, ronndsd

352

ECONOMIC RESOURCES.

. hummocks of gray granite rise through the gneiss. Whilst these
granites are characterized by partial internal decay they are hard rocks which do not disintegrate like the gneisses, and consequently do not give rise to the soils to the same extent as the latter.
The granites and gneiRses are. composed of the same minerals, but the latter is laminated or in beds, whilst the former is compact and homogeneous; yet the proportions vary. In lands formed from_ the decay of stratified limestones the earths may have a heterogeneous structure without traces of any bedding to depths of one hundred feet or more. This has arisen from the removal of perhaps ten times as much calcareous matter as there is now clay and sand; consequently the original structure is obliterated in the gradual settling of the earths. In the case of gneisses and mica schists, as at the Experiment Station, the original rock contained such large proportion of siliceous and only a small proportion of soluble matter, that upon remoYal of the latter it did not permit of enough settling of the remaining mas,'i to obliterate the original bedding; and thus below a depth of from fivr to fifteen feet the materialfl still show the stratification, although the partial decay may reach one hundred feet or more.

ORIGIN OF THE SOILS.

The mineral constituents of gneiss are quartz (giving nse to sand), feldspar (yielding clays with potash, etc.), micas (producing also clays, with iron, potash, etc.), and sometimes hornb1ende (yielding lime, iron, etc.).
In the neighborhood of the farm the quartz predominates in all the rocks, and in some cases to such an extent that when the ot.her constituents, which are those that decay, weather out, beds of' quartzose rock remain, as shown in a depression upon the back part of the farm. This quartz rock is rich in iron, which colors it reel. But usually the feldspars and micas are so intimately
mixed with the quart1:; that this mineral separates into grains anet
makes more or less loamy soil.

SO ILK.

:353

Throughout the origin~! gneiss, veins of compact quartz ramify. Upon disintegration these give rise to angular gravel covering the surface of the ground or producing gravelly soil. Thuo; it is. that the sand of this region is o;imply the residual materials left upon the decay of the gneisses and the granite, from which most of the alkalies have been leached ont, as also some of the finer clayey matter is washed away, leaving loam of varying characteristics. This process of washing out the clay is carried on to such an extent upon the slopes of some of thE' low ridges that even a very light sandy soil is left, for the clay is more easily carried away by wac;hes than the fland. At the same time, owing to the action of vegetable acids upon the soil, the red lands are superficially con-Yertcd into gray, on aceonnt of the partial removal of the iron compounds. The rE'd color of the soils ari~es from the oxidation of the iron contained in them. ThiR reddening proce:-;>< eommonly ex-tend~ only a few feet (eighr.to twehe feet) in depth, but it is some- times seen to a depth of thirty feet, fading out, however, upon receding from the surfaee; consequently, the lightet' earths from a depth are not a! ways the equivalent of the gray land at the surfaee..
The ~oil of the station is deriyed from gneiss containing hornblende, which has furnished part of the iron and most of the lime of the soil, which is decidedly calcareous. The variationf'l are alt local, and dependent to ,;omc extent upon tbe change nf rocks underlying the surface, but mort~ particularly upon tbe effects of the wa:;hings of the surfac;e by rains and rills, in prc:;enee of vegetable matter, giving rise to variable amounts of sand, clay and iron, and also of the plant foods which are held in the earth.
STRL'CTURE 01' THE SOIL.
'Yhen the rain.-; han~ wa,-;hed the surface, then the more ,Qandy soil is composed of ermrse grains of qnartz. However, beneath the heaviest washes the grains are mostly small. A.~ a general feature, the soil is made up of subangnlar (but not watPr-wol'll) transparent grain" of quartz in a matrix of decomposed roek earth, f'Oill-
(~:>)

354

ECONO.MH: REHOURCE8.

posed of clay, feldspar, a small proportion of silvery, shining ::;cales of mica, ferric oxide (coloring niatter), etc. This earthy powder frequently coat11 the grains of quartz ancl adheres to its sur-
o-h- face. The grains of quartz are small, ranging mostly hom 2 -g.-0 to of an inch in diameter and ;;mallet, with a Yery small proportion of large grains, which appear in superficial washes. In descending below the ::;urface the amount of clay increases, as is slwwu by texture and analysi;;.
TY['E OF SOILS.
All of the statiori soib belong to the "re<l land" type, bn t mod-
ified by organic matter and surface washings, so as to produce varieties from light-colored sandy land to the hea,ier redloamf!. In order to illustrate the geologieal variations fom localities were -chosen: (a) In a well, with samples taken at from surface to 7 inches in depth (No. 28); at 2 feet (No. 2-!); at 4 feet (~o. 25); and at from H to 10 feet (No. 26). (b) In the pear orchard, at from .surface to 7 inches (No. 27); at from 20 to 27 inches (.Ko. 28); an1l .at from :36 to -!2 inche.,; (:'\o. 29). (c) At side of ditch, below the ,pond, from the Hnl'face to U inches (Xu :)0); and (d) a surface wa,;hed ~oil in diYision (a), between section,; 12 and 17 (So. 31). In this choice of locations the well ,;how:-; the changing characters of ;appn1ently the same red land to a depth of eight feet, below which apparer1tly a difl~~rent earth shows stmtifieation of decayed rock. In t.lw peur orchard the cnl'tlJ i:-; of one horizon, but the character ehange.~ with depth. In the ditch, near the pond, the naturally deeper earth;; ~re brought to the surfilOe, owing to the erosion of the laud into a small ,alley, but the soil ha:o undergone only partial ~~nperticial weathering;;. In the sanely soil is found a tnw of wa;;hed }, reh:.Ban .~oil;;.
(:,lAR.H"J'll!UHTH'~ AND CO:\ll'OKITIO:\ 01' 'J'l!E SOILS .-\1' 'l'Jill FOl'R 'l'Yl'Jl LOCALITIES.
A. In lhe Wel/.-Samples were taken at time of its excayation
in August, 18}i0. Its location is on a plain. The surface soil is D.ull red. showing a few siiYel'y scales of mica. It is mostly com-

SOILS.

355

1posed of subangular grains of transparent quartz, in size ranging

from :rto to oto of an inch in diameter, coated or embedded in an

.. earthly matrix (No. 23). Below the surface the color becomes a

bright red and more micaceous than above. The amount of clay

:also increases. This eharacter, with slight change;;, continues to a

depth of eight feet. Below this level, the earth is grey and com-

posed of more angular and smaller gtains of quartz, and passes into

decayed rock, showing bedding.



The variations in the composition are seen from four analyses:

No. 23 is surface soil, reaching tu a depth of seven inches; No. 24

is hom two feet; No. 25 is from four feet, and K o. 26 is fl'om eight

to ten feet. Iu the analyses the amount of lime, potash and phos-

phoric acid, soluble in dilute hydrochloric acid (in proportion 1 to

20), after thirty days' digestion, is determined, and this portion may

be regarded as available plant food at the present time or in the

near future.

The size of the grains of quartz bas an important bearing upon

the absorption and retention of heat and moisture and the retention

of plant food.

Analyse8 Nus. 23-26.

Lime (soluble in acid)

. . . . . . . . . :Z. 312

Po.tash (soluble in acid) .. . . . . . . . . . . . . . . 0.094

Phosphoric acid (soluble in acid) . .

0.018

Lime (insoluble in acid) .. .

0. 824

Potash (insoluble in acid) . .

0 579

Phosphoric acid (insoluble in acidi .

0 . 020

Magnesia... . , . . . . . . .

0.125

Soda. . . . . ... . . . . . . . . . . . . . . . . . . . . . . .

0.324

Sulphuric acid. . . . . . . . . . . . . . . . . . . . . . 0. 202

Ferric oxide. . . . . . . . . . . . . . . . . . . . . . . 7. 621

Silica ...... . . .. ... .. .. .. .. . .... .. .. ... G'i'. 6c!7

Alumina ............. . .. ... . ... , . , .... 6.482

Water. . . . . . . . . .. .... ... . . .. . . , . . . . . . . 6. 215

Organic matter.. . ..... . .. .. . .. .. . .. .. G.G56

- Undetermined, loss, etc..

0.831

No. 24. 1.53i-i
0.4~0
o. om o. 01:!
O. o20 0.009 0.312 0.11 0 .286 (i 040 7.125 3.523 4 . 280 1. 738 0 675

1\o. 25. 0.832 0.238 0.068 l 5G4 1.520 0 002 0.420 0.381 0.260 5.8G3 7.900 7.604 3.680 2 .121 0 . 692

No. 26. 0 549 0 . 069 0 .039 1.!148 1.963 trace. 0 .510 0.410 0 . 210 5 924 73.824 8 . 211 4.224 1.636 0 483

100.000 100.000 100.000 100.000

356

ECONOMIC RESOURCES.

B. In the Pear Ul'chard.-I(is on a slight undulation. Thfo,.
color is light reddish with very few particles of micfl. The soil is. loamy with some of the clay washed out, leaving a preponderancP of free quartz, similar to that in the earths at the well. The grains
are mostly from 2 l 0 to otrTJ of an inch in diameter, and even
smaller, coated or embedded in earthy matter; that is,. more or lessdecomposed rocky matter. Below the urface the clay increases in quantity and the color becomes redder.
Th~ samples were takeu from the surface to a depth of seven

inches; from twenty to twenty-seven inches, aud from thirty-six to -

forty-two inches. Their analyse,; may be compared in the table:

No. 27 .

Lime (soluble in acid) ... ... .. , ... . .. . . . ......... . 1.635

Pota,sh (soluble in acid). . .. . ... .... .. .... .. .. 0.315

Pt10sphoric acid (soluble in acid) .. .. . . . ..... .... . . O.Ot\.'i

Lime (insoluble in acid) ... ... . . ... ... .. . ....... .. . 0 321)

Pota,sb (insolnble in acid) .. . ....... . . .. . . .. . . ... .. 0.432

Phosphoric acid (insoluble in acid) . . . .. . . . ~ ..... . 0.060

Ma,gnesia . .. . .. . .. . . ... . . . . ............... . 0 .11 :i

~oda .... .. . .. . ... .. . . . . . . .. ....... ... .. . . ...... 0 .62:Z

Sulphuric acid . . . . ... . .. .. . . . .... .. . ............ 0~310

Ferric oxide . ... . .... ....... .. . , ..... . ...... ..... . li.1HI

Silica . ...... ... .. ... . .... . . , .. ..... .......... . 7J.P30

Alumina .. . .. .. , . .. . ... . .... . .......... .. 5 123

'Vater.... . , .... .. .

.. ... . ..... . . .. . 3 .41i0

Organic matter . . . . . . . . . . . . . .... . .......... 8 152

undetermined, loss, etc .. .... .. .... ......... ... .. . 0.731i

No. ~H . 0 832
0 . 1~2()
0 . 024 1.210 0 834 0 . 072 0 .131 0 .315 0 . 365 4 .S31 75 813 8 .215 -LifiO :2 . ]()f) o.5u:'l

No. ~9.
O. !ll2 0.104 0 . 011 1.5li0
1 . 11~
0.103 0.214 0 . 410 0 372 5.321 15 . 1-!0 l . li!l2
!.~:20
:2. 231i 0. li2fi

100.000 100 .000 100 .000

C. In the Depression near Fond.-The color is light gra.\'ish buff with very little mica in the soil. Th e quartz grains are smaller than in most of the samples and are embedded in mncb clayey matter. The soil may haYe arisen from a hed 'iimilar to that deep down in the well (~o. !30). The sample (No. :n) was taken from, the surface to a depth of twelve inehes.

SOILS.

357

Analy.~is No. 30.

Lime (soluble 1n acid) ---- ---- __ - ------------ --- 1.004 :Potash (soluble in acid) __________ ___________ _. __ ______ 0.065

Phosphoric acid (soluble in acid) ____ __ --- ---- - ----- 0.020 Lime (insoluble in acid)----------- ____ ________ .______ 1.214

Potash (insoluble in acid) .. __ - ----- _ -- ---------- 0.586 .Phosphoric acid (insoluble in acid) - - -- __ -- -- ___ __. _ __ 0.094

Magnesia ----- ___ __ . _-- --_ -------- - ----- - - --- 0.120

;;Soda - - - ------ - - --- _--- --- ---------- - --- - -- .. _ 0.210 ,Sulphuric acid _______ ____ . __ _. ___ ___ ___ ___ -- --- 0.268

Ferric oxide. ________ . ___ -- -----

3.525

:Silica ________ __ --------- ------

79.436

Alumina ____ . _____ . __________ ____ __ . . _ --- -- 7.218

Water _. ____ __ :._ ____ . __ _______ _.. ______ -- - -- ______ 2.321

()rganicmatter ______ __ -------- - --- -------------- 3.590 Undetermined, loss, etc ___ ... ___ . ____________ ._____ __ 0.329

100.000
D. In Division A. between Sections 12 and 17.-It is located on :.a slopiug surface. This is a light colored ~ashed soil, formed from earth similar to that in the pear orchard. The large superficial grains of sand covered the surface where the rains produced the greatest washes, but the sample was taken where less exposed. It is a light sandy loam, mostly made up of semi-rounded grains of
--quartz ( ~h to oh of an inch in diameter) coated with a small
_1>roportion of earthy matter, with a large quantity of organic matter.

358

ECONOMIC RESOIJRCES.

Analysis .i'lo. 3 1.
Lime (soluble in acid) --- --- _---- - - - ---. --- _. ___ _ 1.024:. Potash (soluble inacid)- - - - -------------- . ____ _ 0.120 > Phosphoric acid (soluble in acid)-- . - - - - --- . __ ____ _ 0.042;
Lime (insoluble in acid)_ _ --- - ---- ------ ____ ------ 0.463 Potash (insoluble in acid) __ -- - ---- -- - -- -- - -- - ----- 0.356. Phosphoric acid (insoluble in acid) ____________ .. __ ___ _ O.Oll Magnesia __________ ___ ________ _ . ____ _________ ____ 0.098 Soda- - ----- ------------------ - - -- -- - - _____ 0.5:33 Sulphuric acid. . ---- -- -------- - ---- .. --- -- __ 0.415 Ferric oxide ___ _____ ___ ___ _ _____ __ _ . -- - ------- - ... 4.21.5 Silica .. ___ _____ _ _________ _ __ _________ __________ _ 69.702 Alumina ___ _____ ____ ------------- - - - --------- 6.320,
Water ____ __ --- - -------- - --- ---------- -- - - -- -- -5.111 Organicmatter __________ ...... ____ ------ -- --- _. 10.654
Undetermined, loss, etc __ ..... _. . -- ----- __ ____ --- ---. 0.936

100.000
DEDUCTIONS JI'ROM THE OBSERVATIONS AND ANALYSES.
Note.-As this chapter is a sequel to Chapter XLII. (on the Formation and Characteristics of Soils), much repetition becomes . unnecessary.
Organic Matter.-In the surface soils, except No. 30 in the de-pression, there is a good supply oforganic matter. As most of the land is highly cultivated, part of this is due to artificial application. That at the well is not under cultivation at present.
Clay.-All the snrface samples show a smaller proportion of clay than at a depth, except No. 30. This arises from its partial removal by washings; still the proportion is such as to form only clayey and not heavy clay soil.
Iron.-The ferric oxide is in greater quantities at the surface than below, where the color given to the soil is modified by original matter; still the soils; are all ferrnginous.

tiOILH.

359'

Lime.-It is notable that the total amount of lime increases in one case and rliminishes in another upon descending to a depth. But in both cases it is in abundant quantities, yet its availability rapidly diminishes upon descent from the surface, at the pear ornhard, from 83 per cent. above 7 inches, to 47 pet cent. between 20 and 26 inches; and to only 37 per cent. at :36 to 42 inche:-:. At the well the analyses show 74 per cent. of the lime afi available at the surface; 58 per cent. at 2 feet; 3Fi per cent. at 4 feet, and 22. per cent. at 8 to 10 feet. In the depression near the pond only 45 per cent. is available at the surface; and about 66 per cent. on the sandy surface of Division A. Accordingly, the lime appears more and more locked up as insoluble silicates upon de,.,;cending below the surface. Still the quantity i~; abundant, and further addition. would prove of little value.
Potash.-The absolute quantity of potash rapidly increase" upon descent from the snrfacc, as does the clay, showing that it bas not been extracted irom the original feldspar to the F<nme extent, as. the alkali is removed by surface-action of' carbonic and vegetable acids.
In the pem orchard this decrease progresses from 42 to 13, and to 8! per cent. in descending from surface to 42 inchef'. At the well the surface potash is abnornally low (probably from former exhaustion), yet from 2 to 10 feet the available pota,.;h deerea~:;es from 40 per cent. to 13, and finally to 3! pe1 cent. at 8 feet; whilst the total amount rapidly increases from two feet below the surface downward. Only in the caseH of No. 30 and No. 2G is the quantity of soluble potash low; but in the latter case, it is at a depth ot from 8 to 10 feet, and therefore unimportant. The analyF;es indicate that the soil needs no addition of this food.
Pho8phon:c Acid.-In the pear orchard the total quantity of phJSphoric acid decreases somewhat in descending below the surlace. This superficial excess may be due to artifieial fertilizets, or JWrhaps to the accumulations from the ashes of long succeeding gener-

360

ECONOMIC RESOURCES.

ation of plants. Its solubility at the surface amounts to 50 per -cent. of the total phosphoric acid; 25 per cent. at from 20 to 27 inches, and only 8! per cent. at from 36 to 42 feet.
At the well the amount of phosphoric acid at the surface is far below the normal condition (as is also the potash), of which one half is soluble. Beneath this most of the low amount of phosphate is equally soluble throughout and varies with the kind ot beds it occurs in. These analyses indicate a great superficial exhaJlstion of the land at this point. On a previous page it was noted that the appearance of the soil of No. 30 indicated this earth to have only recently become the surface of the little valley. Now, the amounts of the lime, potash and phosphoric acid by the .analyses indicate that it has be_en exposed to the superficial action of carbonic and vegetable acids, compared with the rolling lands of the farm, only a short while, as the plant foods contained in it are much less available than where the rills have not washed the lands jnto valleys. This case illustrates the agricultural loss by land washes, not by merely removing the superficial organic accumulations, bnt by exposing earths containing plant food not yet availabl~ for absorption.
CONCLUSIONS.
From the analyses and geological structure the soil at the wel represents a very badly worn out surface, particularly poor in phosphoric acid, and with the potash greatly depleted; but yet the latter is sufficient fr,~ good farming. There is an abundance of lime and other constituents.
The soil in the depression (Nu. 30) ha'l comparatively recently been exposed. It is poor in available potash and very poor in .available phosphoric acid, although there is an abundance of both -elements in a form which cannot for a long period be absorbed by plants, but this could be made more available by cnltivation.
The potash in the washed sandy soil of No. 31 is sufficient, and

HOILS.

361

there is plenty of limP. The phosphoric acid falls much below the mark.
In the pear orchard there i.~ an abundance of available lime and potash, but the phosphoric acid is low.
On the present cultivated portion of the farm the lack of vbm;phoric acid appears to con;;titute its only mineral poverty, hut to the old soil at the well an addition of potash might be advantageous.

THE RELATION OF PHYSWAL ~'EATL'RES.
The amount of humus or vegetable matter in these soils reaches 'a fair proportion. As to physical characteristic~;, the dark color causes a great amount of absorption and little reflection of heat. The granular character of the soil r~nders it porouH, with a comparatively ea~;y escape for the excess of rainfall, whilst the smallness of the grains increar-;es its capillarity and aids the iron, clay and humus in the retention of the moisture and its gradual stipply to the growing plants.

CONFORMATION OF RELATIO~ 0~' l'L ~NT GROWTH TO THE SOIL VALUE .
Since this chapter was written, Col. Redding, Director of the Experiment Station, in reply to the query, "Is the location of the well on the site of an old field," says: "It is 'trod land,' with now and then an oak and hickory grove. The impression is that it was an old field, but there is no record." Thi,; section of country has long been settled, and, by the analyses, the surface soil is shown to be badly depleted of phosphoric acid, and, to a less extent, of potash.
In reply to the seco11d query: "Have potash fertilizers been applied to the pear orchard and Division A (sample analyses No. 31 and No. 27), and if so with what agricultural etleet'?" "Yes; under cotton, the additional potash does not produce good results; nor did it with potash and nitrogen fertilizers mixed. But with ;phosphoric acid, or this with nitrogen, there were fine results." Hence the practical demonstration by actual plant growth that there

362

ECONmfiC RESOURCER.

is enough potash and mineral foods in the soil, as above set forth,. but there is a great mineral deficiency in phosphoric acid.
The question of nitrogen food apart from natural humus 1s. outside the scope of this report, as it i.~ artificially supplied.

THE SOILS OE<' THI!: COLLEGE FAR~1 AT ATHE:<!S.

This is situated 011 the summit of a rolling plain, built out of gneisses of the ordinary type, but containing much biotite mica, with very little hornblende.
The decayed rocks come to the owrface at a few points. The soil is or the red type, but not of dark color. Microscopically, the
soil is composed of sub-angular grains of quartz, do of an inch
in diameter and less, in au adhering earthy matrix. The analysis (No. 32) gives the composition of the soil to a depth of twelve inches.

Analy8'is 1\-u. 3:2.

Sand, clay, silica acid, carbonic acid, etc ____ . ____ _____ 88.000

Water ____ _ --------- - ----- ---- -------------Organic matter ____ __ . ------ -------- ----- _____ _ Lime .... _____ __ ___ ____ .. --------------- -- Magnesia _____ ___ ______ ------- - ------- - - - -- -Potash ______ .. _____ .. _ . ____ ___ _ _ ___ . _ __. _ ___ _ Soda ___________ _ . __ . __ _ ___ ___ _. _________ __ _
Phosphoric acid _____ . ______ _ __ ___ _. _ ___ .. - . - -.--
Sulphuric acid . - - ------ ----- - -- --- -------- __ Ferric oxide _______ ___ ___ ,, ___ __ ---- - -- _____ ___ __

4.0:30 4.580 0.290 0.270 0.780 0.680 0.035 0.076 1.204

TotaL __ --- --- ---- __

99.945.

Of the organic matter, the nitrogen amounted to about one-fourth, or over one per cent. of the soil.
In this series of experiments, the washings of the land were. shown by digesting the soil in ordinary water, repeated for thirty-

SOILS.

363::

days, when it was found that even from the silicates 0.8 per cent"" of the potash, 6 per cent. of the lime, 2 per cent. of the magnesia. and over 2 per cent. of the phosphoric acid were washed out besides other substances. These percentages would have been, largely increased had the water contained carbonic or humic acids.
The soil analysis shows a low percentage of lime, and the soiL is poor in phosphoric acid ; otherwise there is sufficient plant food present in the land.
In comparison with the Experiment Station, the smaller quantityof lime is due to the greater absence of hornblende from the-: <Jri gi nal rocks.

IV.-ACKNOWLEDGMENTS AND PROGRESS OF THE SURVEY.
CONTENTS.
BIBLIOGRAPHY OJo' lxEORWA GEOLOGY AND ~~CKNOWLEDGMENTS. THE PROGRESS Ol' THE GEOLOGICAL SURVEY,
BIBLIOGRAPHY OF GEORGIA'S SURVEY AND ACKNOWLEDGMENTS.
'"REPORT ON A GEOLOfHCAL AND ,\GRICULTURAL St:RVEY OF BURKE AND RICH--
MONJl COUNTIES BY .fOHN RUGUJ,ES COTT!NG, AUGUSTA, 183(1,"
was the fitst official geological report made in Georgia. This. little 16 mo volume of 198 pages was addressed to the citizens of those counties under whose patronage the sutvey was made. It is au interesting and, at this day, curious little volume, professedly devoted to economic geology of both crystalline and tertiary formations, but in which speculatio11 is given free rein at the hand of a man well read in the scientific literatme of the day. The littlevolume remains a worthy monument of the early efforts at extending and diffnsing geological knowledge_in the State.
A few years later Sir Charles Lyall rendered southern Georgia classic geological ground by his observations recorded in his "Travels in North America" in 18-!1-42.
The reports of the next geological survey of Georgia, 1874-9> were published as follows:
REPORT OF PHOGHESS OF THE G~;OLtlGICAI . SURVEY OF 18/ii, l'l'. ]-36,
HY Ch;oRCiE LrrTLil, :-'TATE GEOI"OuiS'l'.
SEcOND REPI!>R'r 01' PnO CJRESS OF rrm GEOLOUICAI, ~!,RYE\' OF 18/G, PI'. 1-16,
BY (iEORe<g LrTTLE, 1-iTA'l'E GEOLOGIST.
REPOR'J' 01' TIT!( GEOLO(;[CAL SUR\'EY, 1'1'. 17-1-3, 1\'l'fH ~1AP, RY GEORGE. L!T'I' LI;, in Handbook of Georgia, 1S7ll.
(:1(\'l)

::366

GEOLOGICAl~ SURVEY OF GEORGIA.

"CATALOGUE Ol' ORES, RocKe AND WooDs, Selected from the Geological Survey Collection, for the Paris Exposition by GEORGE LrTTLE, STATE GEOLOGIST, 1878, PI', 1-16.
' TnE TotOGRAPHY, GEOLOGY, ETc., oF GEoRGIA, BY A. R. McOurcrrrN, AsSISTANT STATE GEOLOGIST, PP. 3-158, with maps j In Commonwealth of Georgia, 1885.
'"ToPOGltAl'HY, GEOLOGY AND A(;Rll'FLTURE, BY :MESSRS. LoUGHRIDGE AND McCuTcHr.N. In Cotton Report of Tenth Census, pp. 11-64, with maps.
These last two reports were from the unpublished results of the geological survey, which ceased its operations in 1879 for want of :appropriations, before the report;; were published.
GEOLOGICAl, SURVEY ALONG THE MACON AND BIRMINGHAM HAlLWAY, by
J. W. Spencer Whilst Acting State Geologist, 1889, pp. 1-86,
with plates and map.
This economic survey crossed the Archrean and Paleozoic formation in Georgia and Alabama.
REPOR'l' m PROGRESS OJ' THE (-fEOI.OmC'AL St:RVEY, 1890-91, pp. 1-128, by
J. vV. Spencer, State Geologist.
(This t'eport is mo:;;tly devoted to the Geology of the Cretaceous ~nd Tertiary formations of .~onth western Georgia. The detailed report of Polk county therein is now superseded by the present report.)
GEOLOGICAL SLTRYEY OF GEOlWIA-Tl!E PALEOZOIC' GROl'P, 1893, PP. l--.Jc06, llY J. "'. 8PEXCER, STATE GEOLOGJT.
(This report embraces geological and physical characters, economic resources and -:loils of all the unaltered Paleozoic formations of Georgia, accompanied by geological map, ten plates and thirtyfour cuts.)
Although unofficial in Georgia, the bibliography of Georgia geology would nut be complete without mentioning: "The Lafayette Forrnaii<Jn.," by W. J. McGee, which is an aflmirable and flist.inct (Jhapter of geological history, in which much of the newer geology 10f Georgia is described. " Correlation Papers on the Eocene Sy.stem,"

PROGRESS OF THE SURVEY.

367

~-hy vV. B. Clark, contains a few references. '' C01nla.l'ion Papers -on the ~~fiocene System," by Dr. vVm. H. Dill and G. D. Harris, also needs special notice. " Correlation Papers of the Camb1"ian .System," by C. D. "\Volcott, contains refc~rences which have been used aud acknowledged in the report on the Paleozoic group. 'These publications ha ye been issued (1891-1893) as bulletins by the UniLed States Geological Survey.
"Uve1'th;u8t Fault ofthe Sonthem Appalachian," by C. \Villard Hayes, in bulletin of the Geological Society of America, 1890, pp. 141-154. Due reference to this valuable paper has been made in the text of the report.
"Geology of Tennessee," 1869, pp. 1-550, by ,Tames Safford, State GeologiHt. This report, although not covering Georgia, bas been the foundation of all subsefluent geological work in Paleozoic regions of this State. So, also, several of the Heports of Alabama under Prof. Eugene A. Smith have been of material aid in the stbl.dy of Georgia. Amongst the reports upon the newer formations of southern Georgia, especially bar; the work by Mr. D. \V. Langdon along the Chattahoochee river been of great use. (Bnlletin Geologica.! Society Am., T~ol. II., 189().) The work of Mr. Lawrence C. Johnson on the Southern Tertiaries of the neighboring States has given m;sistance. Prof. Smith's report, upon the Cahaba Coal Fields, and npon northeastern Alabama (by Dr. C. \Villard Hayes, October, 1892) have also contributed to the literature of Ge01gia geology aucl been duly acknowledged in the revi:'iion of thir; report.
A special acb10wledgment of geological as;;istance is due to Dr. C. ~Willard Haye.~, of the United States Geological Suney. This assistance con;;isted of access to his manuscript geological maps from Tennessee to Alabama, coYering port.ions of northwestern Georgia. Tbei':ie incompleted maps were unaccompanied by any report with p2rmis;ion tJ tHe, but not to 1mblish. Thn" the credit clue to my .sur\ey and Dr. Hayes' work becomes mnch more complicated than

368

GEOLOGICAL SURVEY OP GEORGIA.

if his map~ had been published. This condition forced me to re-examine his work while I was tra\eling o;ver nlmost the whole area in order to report upon the local geology and economic resources. This work was greatly facilitated both by Mr. Hayes' wod< and the topographic maps by the United States tmrvey. Accotdiugly the map accompauying t.his report is the result of out own survey with extensive verified adoptions or modifications of Mr. Hayes' work. The report of Prof. Safford, of Tennessee, was ofprimary importance in the study of the geological structure. The topography of the map is from the sheets of the United States survev.
In the preparation of this report I have to acknowledge the valuable assistance of Dr. H. C. \.Yhite, prer;ident of the State College, who bas rendered so much assistance by his chemical cont1ibutions. Not merely do I acknowledge the value of his scientific contribntionR, hut his financial assistance in making hundreds of ebemical analyses without charge to the State, othe~wise this report wonld have fallen sadly Ehort.
A tribute of praise is due to Mr. ,J. M. McCandler:;s, the well-
known Atlanta chemist, who ha::; been chemist to the ;.;urvey, for his careful chemical analysef!, which are scattered throughout this report.
To Prof. ,J. E. willet, rJf 1\Jereer lTniversity, I have abo to
acknowledge ;.;pecial indebtedness for his as"i;.;tance in the survey, especially of South Georgia, and in his valuable contribution to the geology of South Georgia in a paper before the American Association for the Advancement of Science, ~ew York, 1887.
From nnmero ns gentlemen Rcatt.crecl o \er t.hr. conn tr~' I ha \"C receivetllocal ao;sifltance and tQ them collectively I herewith express my tbankR.
In the condnet of the survey I haYc carried ont so far as lay in my power the pro-visions of the governing law of the Rnn~')', . herewith given :

PROGRESS OF THE SURVEY.

369'

'TO REVIVE THE OFFICE OF STATE GEOLOGIST, AND PROVIDE FOR GEOLOGICAL, MINERALOGICAL AND PHYSICAL SURVEY OF 'THE STATE.
No. 688.

An act to revive the office of State Geologist, and to provide for a geological, minemlogical and physical survey of the State of. Georgia, and for other purposes.

u r. ' ,El 'C!ON

B'

enacted O'!J th. . (!)J,eretl As:Hnbly of G"i'01',(jW:,.

' ba.t t h o.fl:i of tnt Q c1 gist i b reby J' ' vived . and the

vernor :l on a pm. t icnb l nftt 1 th pass~\g f thi a t., hull

an u app0int, with t1h co nF; nt of the dviR l'J Bo:u(! a onl}l le~1
p l'SOn to t his office, who suall Lave a thorough.) ci ntil:i.(: J l'M-

tj ca l kn.ow l lge of th seieuce of geo logy amlmiuernl gy and who

i u t un ~ted with any 1:\ h ol or ollege ns an iustrn tor. T h '

State Geologist shall enter upon the duties of his office on th e first

~t\y f ,Tuly, 1890, and uull he l<l un til r m v d by Lhe appointing

p W l' t' r in fficien y in omp ten(\ , t' rni ondu t, or until the

office is ttbo lish~d by the ene1al .:t~ fiRem ly. 'rb office of the

State :.-eologist shall be at the ent of vern:m nt.

1;; . II. B e il ftwthm enacted Tha there ahaJJ ' u.n A l vi oJ'Y

or BOliru unsi ting <Jf th ov rn r of the State ( wbo shu.ll b Pre. i-
n ~ent t iP Utl'CJ ) th ' 101UJD i Sli1 U.el.' Of grionlt.ul'e t he 'tu;t ~

, hoo l n1.rui .i u ' 1'1 th ,, 'tate Tre~sur ~ th ompttollor-GeneraJ
und ,h' , ttO J'b PY- \:m ral. F lU' m.emb ptref:lent a nny me tin g

shall constitJlte ~~ f[U rum fo1 tb t rnnsR.otion f auy b tsin 'l:l'). , 'E . III. Be it f'tlhtbt~1' enacted, Th:tl wo <nnp et nt , i taJl

tut 'coJogi~>tl'l shtill be obosen by- the Advi ory I mwd, wh m~1y

b<l ten'\ov ~ at any t im - hy the a1 point ing power, f~n in mp t no. ,

ineffici ucy, 0 1 ,mlac uduet. It hn.ll be t he duty ol' ~he State ' 1-

ogis and hi a i taut~ to 1livide tLe ,'ate into throe gcologjca l

~e ti n , aH nearly eqllal in Ut' a a n ~ b'e ex p di nt to IJe :li:nowu

ns or t;h (reotgia, ~ i ldl ' :rgia, and 'o ut h ~~~gin, logi ul

eoti oos the Jo 1then1 <lt:ilm ~bu.JI e..:..::t(;U.t(l ftom he tale li tl

southward to the 34th degree of latitude; the Middle Section shall

extend from that degree southward to the 33d degree of latitude;.

the Southern Section shall extend from the last mentioned degree ,

(24)

370

GEOLOGICAL SURVEY OF GEORGI A.

to the southern boundary of the State line; the survey and exploration of each of said sections shall commence simultaneously by :said State Geologist and his assistants, and one thousand dollars of the foregoing appropriation, or so much thereof as may be necessary, shall be applied to each of said sections for an outfit and necessary expenses incident to the prosecution of the work in each section. So soon as a general outline of geological survey of the entire State shall have been made, the State Geologist shall enter upon one of these sections, and assign one to each of his assistants, and under the control of the ji1st named, the corps shall proceed to make a .careful and complete geological, mineralogical and physical survey -of the State; to enter upon record, to be kept for that purpose in his (J/lie ! 11 a Urate l':lttltelt ' nt of the extent of all water-powers, w .ods, rQaufl, spring"' nnd water courses, and the climate, topography l tlll ge u ntl ph ai al chnracter of the country, anci locate the belti:i of ores and useful minerals, building material; report characteristics and composition of the soils, and the deposits of marls and phosphates; to collect, analyze and classify specimens of minerahl, plants and soils, and enter the same upon record; to cause to be presetved in a museum specimens illustrating the geology, mineral()gy, soils, plants, valuable woods, and whatever else may be dis-<.~overed in Georgia of scientific or economic value, and shall make a report of the survey of every county of this State, accompanied with all necessary maps and illustrations. For the purpose of making the analyses contemplated in this act, the State Geologist shall have access to the chemical laboratory of the State. The State Geologist shcdl have. supervi~ion of the enti1e work, and shall be responsible for the accumcy of the same. It shall be the duty of the Sta.te Geologist to malce report8 to the Advisory Board as often a~; required b ' the m and theyshu.ll report to et ch G JP J:!tl l s mbly the pro .l'l'.'; ' U,tld 'ODUttiO U Of the Slll'V,ey j 'i ll ac 'Ul'tlte a (l llll t Of'
money pent and S ll ~l te.v r t. of the State G olo,qist an<~ /,i.~ ct~.~ist ants as ~~ ~lV I IH l mJ l Ld, together with ttll . 11 h infillmn_li(ln a ~
may be deemed necessary and useful. SEc. IV. Be it ful'lher enacted, That the Advisory Board shall
have the supervision of the money expenditures in the prosecution of the work contemplated by this act. 1 he State Geologist shall make to the Advisory Board monthly statements w~der oath of all

PROGRESS OF THE SURVEY.

371

incidental expenses necessarily incurred by himself and his assistants,

.accompanied by proper vouchers, in the discharge of their labors.

The board shall audit such accounts, item by item, and approve or

reject the same, as in their judgment may be right. When an account

is allowe-1., the Governor shall draw his warrant for the amount

thereof upon the funds appropriated by the provisions of this act.

'The Governor, with the advice and consent of the board, may, at

any time, suspend the field operations of the Geological Cotps until

the next meeting of the General Assembly.

SEc. V. Be it fU'rthe1 enacted, That the State Geologist shall

keep his office iu a room to be set aside for that purpose by the

Governor, and the Commissioner of Agriculture shall furnish the

clerical work required by the State Geologist.

SEc. VI. Be it further enacted, That the salary of the State

Geologist shall be $2,500 (twenty-five hundred dollars) per annum,

and the two assistants shall each receive a salary of $1,250 (twelve

hundred and fifty dollars) per annum, to be paid as now provided

by law for the payment of other State House officers.

SEC. VII. Be it furthe? enacted, That the State Geologist, with

the consent of the Board of Advisement, may employ a specialist,

or specialists, at any time.



SEc. VIII. Be it fu?ther enacted, That neithe1 the State Geologist,

nor his assistants, shall disclose to any pe1son, except to the owner

of the land, the result of a survey, until the same is made public by

publication of the report by ~he Advisory Board, which shall bE'

monthly or quarterly.

SEc. IX. Be it further enar.ted, That the State Geologist and

his assistants shall deposit in the office of the Governor, all maps,

surveys, notes, or memorandum of surveys, when the surveys are

completed, which are hereby declared to be the property of the

State.

SEc. X. Be it ftwthe1' enacted, That the sum of $8,000 (eight

thousand dollars), or so mnch thereof as may be necessary, b\), and

the same is, hereby appropriated, annually, for the period of five

years, to carry out the purposes of this act, and this appropriation

shall take effect annually, commencing on July 1, 1890.

SEc. XI. Be it further enacted, That all laws in coufl.ict with

this act are hereby repealed.

Approved November 12, 1889.

372

GEOLOGICAL SURVEY OF GEORGIA.

Til~ PROGRESS OF TilE GB:oLOGICAL SumEY oF GEORGIA.
In the previous bibliography a considerable number of titles appear. Still very littl~ of survey work bas been published, for most of the reports are generalized and do not give either detailed or local information, for few of them were written, as more than preliminary or synaptical papers. Moreover the State reports are entir8ly out of print, and of some not one copy retained in the State is known to me.
With the fragmentary geological progress of Georgia a few distinguished names are connected, whose work has been epoch-making. Of them Sir Charles Lyall stood first in his notes written fifty years ago. Georgia produced Prof. Joseph LeConte, whose great prominence is unfortunately for Georgia associated with other States and countries. The work of Mr. W. J. McGee is epochmaking in the investigations of the late geological history of the State, and in honoring him Georgia reflects the greater glory to herself. Although professedly incomplete, his work is the greatest of any geological investigations that have been made in the State, and its amplification and local application ha;e been a special subject of my study, the full results of which may not now be published.
In soutpwestern Georgia I have investigated the general geological formations of an extensive region extending from Columbus to Florida, and from Milledgeville and Macon to the southern limit of Georgia. Of a large and the best portion of this survey no report has been made; only that of the western portion has been published in a small edition of 500 copies by the State. Of these, copies are now almost unobtainable. In this report the character and distribution of the Cretaceous, Eocene and Miocene systems of the region are described with some notice of the Lafayette and Pleistocene formations. In this work I have to acknowledge the invaluable assistance of Dr. W. H. Dall in connection with paleontologieal studies. From the economic standpoint special attention was given to the building materials, fire and pottery clays, marls

PROGRESS OF 'l'HE HURYEY.
and phosphates, and to the most important of all geological questions relating to southel'll Georgia, the artesian wells. In that report I have laid the foundation of the knowledge of the geological structure, which admits of rendering the often malarial regionH healthful in a count.'r which otherwise is frequently the most favored portions of Georgia. In these investigations I havE' carried on the work so far as means were at my disposal; and my last field work was in connection '<vith building materials and pho::;phates of southeastern Georgia. But all of this work ir; now almost unavailable.
A considerable amount of preliminary work has heen done in middle Georgia, but as yet not sufficient to make a satisfactory report.
This report upon the Paleolr.oic belt, as it is to appear in an edition of 2,500 copies, will probably be distributed sufficiently widely to make known the features of that part of the State. whilst this report is primarily an er:onomic survey, it is yet more or less scientific and educational. Every State geologist, or any geologist, has to constantly contend against the ignorant, or the schemer, who suppoEe that the geologist':,; primary duty is to simply give a list of mining property, which promoters can jump upon, obtain for a song, and sell to l::iomebody else. If nature has not. put valuable deposits where desired, then the geologist is reproachable for not having controlled nature. Th ere can be no greater abuse than :mob as is hurled against a geologi::;t and hiH science, when his quiet testimony condemns a "j1andulent" gold, coal or other mine(?).
The legitimate work of a smvey is to discover and make known the structure of the rock formations and the relations theteto of everything of economic oe scientific interest-not alone precious ores, but building materials, supply of water, the character of the soils and everything that can be made useful. In the deposits of useful ores, etc., his duty is not so much to gi,,e a eatalogue of properties, but of the belts of their occurrence, and how

374

GEOLOGICAL SURVEY OJ<' GEORGIA.

they are related to the rock formations, so that private interests can start where he leaves off and develop the resources with the smallest chance of failure. The work is also educational, so that the student can learn something of the region and extend thP. knowledge of the science.
The report upon Northwest Georgia is essentially economic. But in order to understand local developments, the geological structure, apart from utilitarian value, had to be determined. In this connection the report is also educational, for the general principles of the science are applied to the local variations. By this means, the distribution and modes of occurrence, and character of Red and Brown Iron ores, ~Manganese and Aluminium ores, Coals, Building Materials, or Limestones, Sandstones, Flags, Clays and Paving Materials, Variability of Soils, and the Physical Features and Water-powers of the country, are set forth-in short, an attempt at giving all the resources of the country which bear upon its habitability and progress, as based upon its geological foundation. Besides these positive advantages of the survey, still greater arises from the negative, in saving people foolish search for what they cannot obtain. Thus I have seen the mining of shale for coal, working gold (?) mines in limestone, and numerous other works as impossible, although not so apparently absurd. In impossible artesian wells in Georgia alone, the advice of geologists would have saved more than the cost of an elaborate survey of the State, and has actually saved much money.
With this report of north western Georgia there is a general record of its character, and the resources which can be obtained without the cost of making special surveys. Private interests will develop these resources, but this report will be the basis of all future work.
The present report has been written for the people of Georgia, with the omission of as many technicalities as possible, so that it may be used by any one with ordinary education.

V,-T ABLE OF CONTENTS,

PAR'r I.-GEOLOGY OF THE PALEOZOIC GROUP.

CHAPTER I.

SKETCH OF THE GENERAL QEOLOGICAL STRUCTURE OF

NORTHWEST GEORGIA . . . . . . . . . . . . . . 7

No1'E . . . . . .

LITHOl-OGY: Igneous Rocks; Sedimentary Rocks; Limestones; }!eta-

morphic Rocks . . . . . .

. ..

8

FoRMATION AND DEs'rRUCTION OF RocKs: Cause of Rock Decay;

Formation of New Beds of Rocks . . . . . . . . . 9

J~FFEC'rS OF TERRESTRIAL MOVEMENTS ON GROWTH OF STRATA: Oscil-

lation; Unconformity; Succession of like and unlike Materials; Fossils;

Position of Strata . . . . . . . . . . . .

11

GREAT GEOLOGICAL BELTS OF GEORGIA . . . . . .

H-

INCOMPL"E'l'ENEBS OF THE GEOLOGICAL FoRMATIONS AND MODE OF

REGIONAL GROWTH . . . . . . . . .

15

DISTURBANCES AND DISLOCATIONS OF THE ORIGINAL BEDS: Elevation

and Folding of Beds; Faults; Effects of'Folding upon the :Materials

of the Beds; Effects of Atmospheric Action upon the Folds .

16

DECAY OF SUPERFICIAL HOCKS IN NoRTHWEST GEORGIA .

22

ORIGIN OF VALLEYS , . .

2-!

ltECENT GRA YELS AND LOAM~ . . . .

2(}

CHAPTER II.

GEOLOGICAL GROUPS OF NORTHWEST GEORGIA.

27

TABLE OF GEOLOGICAL GROUPS. . . . , . . .

27

GEOLOGICAL SYSTEMS OF NoRTHWES1'ERN GEORGIA-Eastern Border

of Unaltered Formations; Range of Geological Formations .

27

PALEOZOIC FORMATIONS OF GEORGIA-Table; Value of Fossils

29

THICKYESS OF THE LOWER pALEOZOIC FoRMATIONS; OF THE UPPER

pALEOZOIC ROCKS .

. \..

31

J!'AULTS

3~

376

GEOLOGlCAL SURVEY OF GEORGIA,

CHAPTER III.

GENERAL CHARACTERS OF THE CAMBRIAN SYSTEM.

34

TABLE . . . . . .

34

OcoEE SERIES . . . . . . . . . . . . . . .

34

CHILHoWIE s~:RIEs . . . . . . . . . . . . . . . . . . . .

35

OosTANAULA SERIEs-Coosa Valley Phase; Oostanaula Fault; Con-

nasaugn Valley Phase . . . . , . ,

. .. . .. ..

37

CHAPTER IV.

GENERAL CHARACTERISTICS OF THE ORDOVICIAN SYSTEM 42

(LOWER SILURIAN Olt CAMBRO-SILURIAN.)

TAnr.E . . . . . . . . . . . . . . . . . . . . .

42

KNOX SERIES . . . . . . . . . . . . . . . . . . . .

42

CHICKAMAUGA SERIEs-Maclurea Limestone; Deaton Ore .Beds; Rock-

mart Bl!ltes . . . . . . . . . . . . . . . . . . .

45

v. CHAP TER

'GENERAL CHARACTERISTICS OF THE SILURIAN SYSTEM . 48

RED ~IOUN'l'AIN S ERIES .

48

CHAPTER VI.

.GENERAL CHARACTERISTICS OF THE DEVOKIAN SYSTEM 50

CHAI"l'ANOOGA BL.A.CK SHALES: . . . .

50

CHAP'l'ER VII.

GENERAL CHARACTERISTICS OF THE CARBONIFEROUS SYS-

TEi\-1 . . . . . . .

51

FORT PAYNE CHERT .

51

FLOYD SHALE . . . . ,

52

MouNTAIN LIMES1'0NE

52

GOAL M EASURES . . .

52

CHAPTER VIII.

RECENT FORMATIONS, AND EVOLUTION OF NORTHWEST-

ERN GEOl~GIA . . . . . . . . .

55

LAFAYETTE(?) AND M ODERN SERIES .

55

EvoLUTION oF NoRTHWKST GEoRmA.

5tl

CONTENTS.

377

CHAP TER IX

."!'HYSICAL FEATURES OF THE COVNTRY UNDERLAID BY

P ALE O ZOIU ROCK S . . . . . . . . . . . . . . . . . . 60

GENERAL FEATURES OF ~ 1) THE COO SA VALLEY AND ITS EA STERN

BouNDARIEs, (2) NoRTHwEsT OF THE CoosA BA SIN . .

60

CHARAC'l'ERISTI CS OF RIVERS AND STREAMS, , .

. . . . . (i4

MINOR P HYSICAL FEATURES: In Polk, Floyd, Bartow, Gordon, Mur-

ray, Whitfield, Catoosa, Chattooga, Walker and Dade counties

47

LAKELETS, SINKS, AND CAVES .

74

TABLE OF ALTITUDES . .

76

CHAPT.ER X.

;LOCAL GEOLOGY OF POLK COUNTY

77

CHILHOWIE AND 00STANAULA SERIES .

77

KNOX DOLOMITE 'SERIES . . . . . . . .

78

CHICKAMAUGA SERIES: Maclnre a Limestone; D eaton Ore Beds; Rock-

mart Slate . . . . . .

82

RED MOUNTAIN SERIER . . .

86

Sun-CARBONIFERous SERIES .

86

MoDERN DEPOSITS . . .

86

CHAPTER XI.

LOCA L GEOLOGY OF :FLOYD COUNTY

87

00STANAULA SHALES

87

KNOX DOLOMITE . .

92

RED MOUNTAIN . . ,

94

S u n-CARBONIFEROus: Fort Payne Chert; Floyd Shales

96

COAL MEASURES . .

96

LAFAYETTE( ?) AND MODERN . . . .

97

CHAPTER XII.

J,OCAL GEOLOGY OF BARTOW COUNTY

99

OosTANAULA SERIEs . . .

99

KNOX DOLOMITE SERIES .

102

CHICKAMAUGA SERIES.

107

LAFAYETTE (?) SERIES

107

MoDERN SERIES .

107

JV10UND8 . . . . .

107

378

HEOLOGICAL SURVEY OF GEORGIA.

CHAPTER XIII.

LOCAL GEOLOGY OF GORDON COUNTY. OosTANAULA SERIES . . KNOX SERIES . . . . . . . . RED MouNTAIN SERIES . . . CHATTANOOGA BLACK SHALE SERIES Sun-CARBONIFERous SERIES: Fort Payne Chert and Floyd Shales LAFA.YE1.'TE AND MODERN SERIES FAULT . . . . . . . . . . . . ..

10&
lOS 109
110 11()
110 110
111

CHAPTER XIV.
LOCAL GEOLOGY OF MURRAY COUNTY OosTANAULA SllRIES KNOX SERIES . . . . . CHICKAMAUGA SERIES .. RED MOUNTAIN SERIES LAFAYET1.'E AND MODllRN .

112: 112' 112' 113 113 113

CHAPTER XV.
LOCAL GEOLOGY OF WHITFIELD COUNTY OosTANAULA SERIES . KNOX SERIES . . . . . CHICKAMAUGA SERIES . RED :MouNTAIN SEHIES CHATTANOOGA BLACK 8HALEfS . Sun-CARBONIFERous SERIES .. LAFAYETTE AND RECENT SERIES FAULTS . . . . . . . . . . . .

115..
115 11& ]16 117 117 117 118 118

CHAPTER XVI.
LOCAL GEOLOGY OF CATOOSA COUNTY 00STANAULA SERIES KNOX 8ERIE8 . . . . . . CHICKAMAUGA SERIES . . RED MouNTAIN s~:RIES CHATTANOOGA BLACK SHALES . Sun-CARBONIFERous SERIES .

119119 119 120 121 121 122.

CONTENTS.

379

CHAPTER XVII.
LOCAL GEOLOGY OF CHATTOOGA COUNTY
OosTANAULA SERIEs . KNOX SERIES . . . . . CHICKAMAUGA SERIES .. REn MouNTAIN SERIES CHAT'l'ANOOGA B LACK SHALES . SuB-CARBONIFERous SERIEs COAL MEASURES . .

123123 123124 124 12& 126 12;

CHAPTER XVIII.
LOCAL GEOLOGY OF WALKER COUNTY
00STANAULA SERIES . KNOX SERIES . . . . . CHICKA.MAUGA SERIES . . RED MoUNTAIN S ERIES . CHATTANOOGA BLACK SHALES . SuB-CARBONIFEROUs S ERIES . 00AL MEASURES .

130 13()13(}
131 13Z 135 135 136

CHAP'l'ER XIX.

LOCAL GEOLOGY OF DADE COUNTY

141

KNOX SERI ES . .

141

CHICKAMAUGA SERlE~ . . . .

141

RED MouNTAIN SERIES . . .

142

CHAT TANOOGA BLACK SHALES

142

Sun-CARBONIFERous SERIES

142

COAL MEASURES . . .

143

CHAPTER XX.
RECENT FORMATIONS WEST OF TAYLOR'S RIDGE . . . . 146

:380

GEOLOGICAL SURVEY OF GEORGIA.

pART H.-ECONOMIC RESOURCES. TABLE oF EcoNOMIC REsouRcEs H.EPRESENTED ON MAP . . . . . . . . 149

CHAPTER XXI.

1BROWN IRON ORES AND THEIR MODES OF OCCURRENCE . 150

KINDS OF BROWN ORE . . . . . . . . . . .

150

SouRCES oF BROWN ORE . . . . . . . . . .

151

MoDES OF OccuRRENCE oF BROWN ORE: :Note ; Iron; Ore of the Knox

Series; of the Deaton Series; of the Sub-Carboniferous Series .

152

CHAP TER XXII.

LOCAL DISTRIBUTION OF BROWN ORES .

159

KNox ORES IN Por.K CouNTY: In the basin west of Little Cedar

Creek; V alley adjacent to E . T., V . & G. Railway; Along East &

West Railway of Alabama; Fish Creek Distri ct; L ong District;

Re capitulation

. . . . . . . . . . . . . . . . . . . 159

KNoX ORES lN FLOYD CouNTY : Cave Spring District; Spring and

Silver Creek Districts; Recapitulation . . . . . . . . . . . . . . 16:1

KNoX ORES IN BARTow CouN'l'Y : Rpring and Silver Creek Districts;

Tom Creek and Connesenna Districts; Recapitulation . . . . . . 167

ORES OF THE ]\'IE1'AMORPHIC ROCKS

.

169

DEATON ORES . . . . . . . , , , . . .

169

Sun-CARBONIFEROUII On.Es . . . . . . .

169

BROWN ORES IN GORDON, MURRAY, WHITFIELD, CATOOSA, CHAT'l'OOOA,

WALKER AND DADE CouNl'IE~: Knox Ores; Deaton Ores; Sub-

Carboniferous Ores . . . . . . . . . . . . . . . . . . . . . . 170

CHAPTER XXIII.

'THE COMPOSITION OF THE BROWN ORES

172

MonEs oF WoRKING THE OREs ; ORE PRonuC'l' i OcHRE WonKs .

174

CHAPTER XXIV.

IRED IRON OR "FOSSIL" ORE

176

HEMATITE "FosSIL" ORE

176

MonEs oF OccuRRENCE . .

177

CONTENTS.

38]

CHAPTER XXV.

LOCAL DISTRIBUTION OF FOSSIL OHB~ .

181:

DIRT SELLER .i\Io uNTAIN

181'

SHINBONE RIDGE . . . . .

181

LOOKOUT V ALLEY . . .

184

TAYLOR'S AND DicK'S RIDGE

185

CHAPTER XXVI.
COMPOSITION OF FOSSIL OHE . . . . . .

. . . . . . . . . 187'

CHAPTER XXVII.

THE IRON FURNACES

. . . . . . . . . . 1891

CHAPTER XXVIII.

MANGANESE
UsEs OE MANGANESE . . . . . . . . . . . . . .
KrNDS or' ORE: Pyrolusite, Braunite, Psilomelane, Manganite, Wad
MANG ANESE O R ES o F rHE KNox Sa:Rus IN GEORGIA . CoMPOSITION oF THE ORES MoDES oF OccuRRENCE

190 190 191 192 193 195

CHAPTER XXIX.

LOCAL DISTLnBUTION OF MANGANESE ORE~ IN THE KNOX SERIES . . . . . . . . . . . . .
CAVE SPRING D r sT.RICT . . WooD LANDS OR BARNSLEY Drs'l'RIC1' . TuNNEL HILL DrsTRWT . . . . WoRKINGS OF MANGANESE DEPOSITS .

200' 2u0 203 203 204-

CHAPTER XXX.
ORIGIN OF MANGANESE AND IRON DEPOSITS . . . . . . . . 205

CHAPTER XXXI.
ALUMINIUM ORES
NoTE oN ALrM AND ALumNru~r . . . . . . SouRCES oF ALUMINIU~r-Beauxite, Cryolite, Kaolin, Clay HALLOYSITE A:<!D GIBBSITE . . . . . . . . . . . . . . ,

210 210 211 212:

382

GEOLOGICAL SURVEY OF GEORGIA .

CHAPTER XXXII.
BEAUXITE . . PROPERTIES . ANALYSES DISTRIBUTION AND COMPOSITION OF Ji'ORElGN 0RJJ:S . UsEs OF BEAUXITE. , MoDEs oF OccuRRENCE ORIGIN OF BEAUXITE BEAUXITE IN G E ORGIA
CHAPTER XXXIII.
ALUMINUM, ITS SOURCES AND USES, BY R. L. PACKARD
BEAUXI'l'E IN EUROPE . BEAUXITE I N AMERICA ANALYSES , :1\tiJJ:TALLU RGY . PRODUCTION . PRIC!l;; UsEs . MEl'ALLURGICAL UsEs. SOLDERIN G ALLOYH . . . . . . .
CHAPTER XXXIV.
COAL . . .. . .. . ON SAND MouN'l'AIN ON LooKOU1' MouN'l'AIN ANALYSES OF COAL AND 0010: . CoAL MINES . .
CHAPTER XXXV.
LDIESTONES, LIME ROOKS, CEMENT ROOKS LIMESTONES DoLOMITE . HYDRAULIC CEMENT DISTRIBUTION OF LIMESTONES IN GEOL OGIUAL J!'ol:MATIONS 00STANAULA. LIMESTONE AND ANALYSES ; 0EMEN'l' ROCK . KNOX DoLOMI'fE AND ANALYSES , . . . CHICKAMAUGA LIMESTONE A ND ANALYSES . . DEATON LIMESTONE . . . . . . . . S un-CARBONIFERous Lnr E sTONE AND ANALY~EH.

214 214 215 220 221 224 225 226
281 231 233 236 237 237 238 241 242 243
2-17 247 254 258 259
261 261 262 262 262 262 265
268
270
271

CONTENTS.

CHAPTER XXXVI.

SANDSTONES . . .

272

OF THE CHILHOWIE SERIES

272

OF THE OusTANAULA SERIEs .

272

OF TIIE RED MouNTAIN SERIEs .

272

OF THE Sun-CARBONIFEROUS SERIES .

273

OF 1'HE CoAL MEASVRES . . . .

274

CHAPTER XXXVII.

SLATES . ..... .

. . . . . . . . 275

CHAPTER XXXVIII.

CLAYS AND BRICK PAYEMENTS . . .

276

NoTE . . . . . . . . . . . . . . . . .

276

BRICK P AVE~lENTS AND KLNIJS OF CLAY REQUIRED .

277

CLAYS OF NoR'l'HWEBTERN GEORGIA AND ANALYsEs; Composition of

Clay; Kaolin Type; Residual Clays; Clays from Disintegrated

Shales; Alluvial Clays . . . . . . . . . . . . . . . . . . . . . 279

CHAPTER XXXIX.

WATER POWERS AND TIMBERS ..

. . . . . . . . . . 289

CHAPTER XL.

THE LOCATION OF ROADS AND THEIR REI,ATIONSHIP TO

THE PHYSICAL AND GEOLOGICAL FEATURES.

290

NoTE.-RELATION oF RoADS TO GEoLOOICAI. STRl'CTU RE

290

ROADS ON 00STANAULA SHALE. .

291

ROADS ON KNOX DOLOMI'l'~: . . . .

292

ROADS 0~ CHICKAMAUGA SERlES .

293

ROADS ON RED MouNTAIN SERIES .

293

RoADS oN FoRT PAYNE CHERT .

293

ROADS ON FLOYD SHALES . . . .

2\13

ROADS ON MoUNTAIN LIMESTONE

294

ROADS ON COAL MEASURE~ . . .

2il4

SUMMARY . . . , . . . . . . . .

294

NOTES ON CoNSTRUCTION OF ROADS

295

SOURCES OF ROAD MA1'ERIAI. . . .

296

CHAP'l'ER XLI.
GOOD ROADS VERSlTS BAD ROADS ... , .. .. , , . 298

38-!

GEOLOGICAL SURVEY OF GEORGIA.

PART Jll.-SOILS. TABLI OF AGI.UCUL'l'URAL FEATURES REPREtiEN'l'ED ON MAP . . , , 3ll'

CHAPTER XLII.

FORMATION AND CHARACTERISTICS OF SOIL OF '!.'HE

PALEOZOIC J3ELT F ('EOR IA .

312

C OLOR DISTIN C 'l'!O,~M . . , . . . . . . . .

312

ORIGIN OF '!'HE 1\f.A:rl!JIUAJ,f; F 'I'Il '& 'OILS

314

How THE SoiLS WltiU: l~tHt~tJ!:D: The Formation of Limestone Soils as
ill nstrauecl l'rtH'n ~11 Knox. Dvlorn ite ~ ri os; Sour OS or Plnnt Foocl in Lime. I.Qn ; "Fol'luution of t:lh!l!o Soils ; F'lrmution of Sr\nily 'oil ;

J~ l'rnnliou pt' roop ,"' il ; l?Q t'tl\ntion of Allu vial Soils . . . . . . . 314

A C lUl.A'l'ION~ AND lRJ111C'J' I' ll(b\N_i JIL\'i"l'lrn HI , '011.::1 . . . , 318

K1N'n. AN:O 'PIH~l .n. PnaPEll'l':u ;s m~ SolLSi 'nndy F:ll)i ls; lay :-1oils;

nlcnrenus nnd [ILJly uils; Ji'erqgi rlOIJS. ils . . . , . , 321

!Ut,j..~'I.Pl>.~ 011 liEA'L' ANJ> J\iOJSTU LUi '1'0 :Pm:lilT '..U. 8'1'f\ I.''I'UIIJ;; ,\.lU)

Ll;llt Of' .- Lf..S: IUlily Soil j aloa:reous so.iJs; Olayey Soi l . . . 322

E ~SA lH ONl'l'rH'IJEN'l'll H' l'l. AN'J' Foo;n: JJ:Jom !lt.ll :Modi 11m <lf

'up[,ly; l"ixing of Pla nt Food; Suporphosplulte vf L in:le; PoL h

t:!nlt~; Arllrn0111A. oHa . . . . . . . . . . . . . . . . . . . . 323
E 'J'JMA1'1NG 'I' H~J Ii1.1E rn.' SOli : Vnll'\e f AnAlyses; Lim ; Pbos-

phol'i<~Acia; Po~nsl1; Sorl n.; ,_,l lphnric Aeiil; Oh lol'ine; li'OI'L'iO hlcl;

Moisture; PhyRicul 0 ndl l'.ion

. . . . . . . . . . . . 32&

CoNsUMf"''J,O ' t>Y .MJlilirtAI. o srr'l' UI~'tl'l'fi :.; Pt,A 11' FOOl) t1Y '0'1'-

TON, CoRN AND WHEAT . . . . . . . .

. . . . . . . B27

CHAPTER XLIII.

G-JllOLOGI AL D HE~O AL l.tli:LATlON rrn~ Ol!~ THl!: OILS

UJl' THE PALID07. IO !fORM TI NS . . . . . . . .

32V

' t' LL~ 01 'lUr( Oosr.~..N;HfLA Sl'lliiES: An ly. s . . .

329

SCilL 01~ 'l'llil KNO Siml~t~: Lted Soils 1 Gr:ay 'oils ; A.nalysr

337

ou.s OF 'I'!IB 'nr lwHI A( ClA Sr-:11u~ : nnl ,ystl,

342

,'O(J1!> PTIIIt I J"-J) l\lOu:N'l1:A.tN Intm8: Anulyses . .

344

8oTLS OF 'I'll It S'lill- AU:Ho:Nu.rmou.: S~n;s: Jl'ort Pn.yno hort; ]1Joyd

Shtl101l; .MoUJltuin Lim st<ma; Analyses .

345

, Oil.!< CJF' 'l'lfi~ C A.l. J'v[ II!'AS1llt 11! , , ,

347

LARAn~T'xE AND r;r. VIAl. Sou.:-! . . . . . . . .

347

ll! .I!IRAT. NOTlCS O:N IJMI?<:IST'I'TO.N A"n .PuY~li~AL Fn P'Kit'rTY.S n~ 011 . 34!l

CONTENTS.

385'

CHAPTER XLIV.

-GEOLOGICAL RELATIONSHIP OF THE SOILS OF THE AGRI-

CULTURAL EXPERIMENT STATION OF GEORGIA AND

OF THE COLLEGE FARM ...

351

GEOLOGICAL CHARACTERISTICS OF THE VICINITY OF THE STATION .

351

ORIGIN OF THE SOILS .

352

STRUCTURE OF THE SOILS. . . . . . . . .

353

TYPE OF THE SoiLS . . . . . . . . .

354

CHARACT ERISTICS AND CoMPOSITION OF THE SoiLS AT FARM .

354

DB:pU CTIONS FROM OBSERVATIONS AND ANALYBES

358

CoNcLUSIONS . . . . . . . . . .

360

THE RELATIONS OF PHYSICAL FEATURES . . . . . ,

361

CONFORMATION OF TH}; RELATION OF PLANT GROWTH TO THE Sorr,

VALUE . . . . . . .

, 361

SoiLS OF 'J'HE CoLLEG E FARM A'r ATHE)IS . . . 362

PART TV.-ACKNOWLEDGMENTS AND PROGRESS OF SURVEY 364

PART V.-CONTENTS _____ _ _ _ ___ __ ________ - -- - - ------ 374

pART VI.-INDEX - - -- - - - - - - .. --- - --

389

(25)

386

GEOLOGICAL' SURVEY OF GEORGIA.

PLATES.

OPPOHT!i I.-DEATON IRON ORE PITS. . . .. .. . .... . .. . ......... FRONTI SPIECE 1

!I.-KNox DoLo~nTE BLUFF, SHoWING STRATA ALO:-.IG Rmm RAILWAY 42

IlL-KNox DoLoMiTli: BLU~' F, Sot;TH oF DALTo:-:; LEDGES OF R0cK

RISING INTO RESIDUAL CLAY .....

43

IV.-LADD 1S MouNTAIN, SHOWING ~'OR~I OF RIOGES WEATHE R IN G OU~'
OF KNOX DOL OMITE, COT'rON l' !F] LD IN FOREGROUND. . . . . . . . . 44

V.-SHINBONE (ORE) RIDGE AND LOOKOUT MoUNTAIN, SEEN l'HOM
RISING FAWN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
VI.-LooKOUT Mo U NTAIN, ABOVE RISING FAWNj 1000 FEET HI GH , AND SHOWING CONGLOMERATE ESCARPMENT ..... . . . . . . . . . . . . . oo o. 53

YIIo-BnowN ORE RID G E AND PIT.s AT GRADY IN RESmu-AL CLAY DE-
153 mv~;D FROM KNOX DOLO~UTE . .. . o o. o .. . . . . . . . . . . .. o . o

Vllio-BROWN OnE WoRKINGS AT ETNA, IN RESIDUAL CLAY Ol' KNox
D O L O i\! I T E . . . . . . 160 0 0 0 0
IXo-MINING RED "FossiL OnE" AT NEw ENGLAND C I TY (Corum) .. 184

Xo-LIMESTONE BLUFF OF THE OosTANAULA SHALES, AND KILNS AT

C E i\l E N T 0 0 0 0 0 0 0 0

264

(Noteo-The above engravings are from pholographs by the author.)

GEOLOGICAL MAP.
SCALE, FIVE MILES AND ONE INC H.

CONTENTS.

387

CUTS.

I' AGE.

1.-LIMESTQNE STRATA PROTRUDING THROUGH RESIDUAL CLAY. , . , ..

10

2.-UNCONFOR~HTIES . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . .. , . . . . .. .. .

12

3.-MAP OF PRIMARY GEOLOGICAL GROUP OF GEORGIA ........ . , , . , ,

14

+.-MINIATURE F~LDING OF STRATA ALONG OcoEE RIYER . . . . . . . . . .

17

,'j,-FOLDING OF STRATA SOUTH OF CARTERSVILLE. , ...... , . ..... . .

18

6.-GREAT UNDULA'l'IONs OF STRAT-A (LooKouT AND SAND Moi:NTAINs) .. 18
7.-FOLDING AND FAULTING OF STRATA ALONG ETOWAH RIVER. ,, ..... . 18

fl.-OvERTHRUST FAULT WEsT oF RoME .... .. .. ..... . ..... .. ... . .. .

19

1).-FAULTS AT CAVE SPRING ... ... . . .... ........... . ... . . .... . .. 20

10.-EFFECTS oF DEcAYING LnmsTONES, SouTH OF CAYE SPRING .... .. . 23

11 .-MAP OF DIVIDE AT HEAD OF LOOKOUT CREEK1 SHOWING EFFECTS

OF EROSION ............... . .... .'. . . . . . . . . . . . . . . . . . . . .. 25

12.-CROSB SECTION OF 8A~IE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . 25i

13.-REPETITION 01' STRATA OWING TO FAULTING ..... ~ ..... .. .

33

14.-SECTiON ACROSS COAL MEASURES .......... , ............. , . ... , , .. 54

15.-SE'CTION SHOWING ENORMOUS DENUDATION OF STRATA ...... .

59

16.-SECTION FROM 00STANAULA RIVER TO CARTERSVII.LE ACROSS THE
CoosA BASIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63:

17 ,-SEcTioN FROM RoCKY FACE TO COHU'f'fA MOUNTAIN ACROSS THE

CoosA BASIN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..... .

63;

18.-JIJNCTION oF OosTANAULA AND KNox SERIES 19.-FAuLTs IN vVHrTFIELD CouNTY ...... .. ...................... . .

101
118;

20.-DENUDATION IN CnATTOOGA CouNTY ............ ........ . , . , , .

128

2L-FOLDING AND FAULTING AT WESSBORO ..

134

22.-CLAY "HoRsE" AT GRADY:. . . . . . . . . . . . . . . . ............... .

155

23.-PI.AN OF DEATON MINE ..................... . ............ . ... 169

24.-FAuLTING AND FoLDING oF RED MouNTAIN SERIES....... . . . . . .

178

25.-DECAY OF RocK AND OCCURRENCE OF MANGANESE ORE ...... , . . . . . 197

26.-FORM OF BEAUXITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....... 215

27.- SECTION oF CREST OF BAD RoAD GRADIEN'l' ...................... 295

28.-GOOD RoAD IN FRANCE, WITH HEAYY LOAD OF HAY ... . . . . , .

300

29.-BAD MuD RoAD-FouR HoRsEs AND WAGON MIRED .. . ..... , . 301

30.-AVERAGE FAIR AMERICAN RoAD ................ ....... .... , ... 301

31.-GooD RoAD IN FRANCE, SHADED WITH TREES. . . . . . . . . . . , .. . .. , .. 302

32.-GooD ITALIAN RoAD...................... . . . . . . . . . . . . . . . . . . 303

33.-GOOD RoAD IN FRANCE, PASSING THROUGH A TUNNEL . .... ...... 304

34.-FORMATION OF SoiL FROM DECAY OF LIMESTONE .................. 315

VI.-INDEX.
Absence of Gravels West of Taylor's Ridge--------------------146 Acknowledgments ______ ------------ ------- - ------- - --- ----364 Agricultural Features, Table- - ------ - --- - ----------- - - ----- 311 Algre------------- ----- ---------------------- -----------104 Altitudes Coosa Basin --------- - ------ - ------- - -- -- - - - - 61
Northwest Georgia_------------ __ ----- ___ -- _______ 64 Table of_ ______ -- --- ------------- - ------- - ------- 76 Alum------- ------------------------------ - - ----- --------210 Aluminium - ----- . --- - --- ----- ---------- -- -------------210 Analyses of Aluminium Ores (see Beauxite and Analyses). Aluminium, Alloys of_ ____ __ . ------------------- ______ 243, 245
Bronze ________ _______________ : ________________ 224
Effects of Fluids 011---------- ---- ---- _- _ ________ 241 Metallurgy of_--------------------------- _______ 237 Ores (see Beauxite, etc.). Properties of_ -- ------- - --- ------ - ---- . --- - --242 Solderi11g__ - --- - - - - - --- -------- - . ---- - - -- ______ 2 4~ Sources of_------ - ------.------------------ _210, 231 Strength o'------ - --- - - --------- _--- -- ---- - 244 Uses of_ ____ ---------------------------- _______ 231 Analyses of Beauxite- -------- ------------------------ _215-237 Brown Iron Ores -------------------- - ------- __ 172-174 Clays--------------------- ------------------278-288 Coal and Coke_-------_-- __________ -- ___ --- ____ 258-259 Limestones_.__ ----- _--- _------- ____ -___ -- ______ 263-271 Manganese __ ----_-- ______________ __._____ -- ______ 193 Red (Fossil) Ore ________________ ---______________ 187
Soils __ --------. . - _-------- _____ --- ------ --- _230-264
(389)

.390

GEOLOGICAL SURVEY OF GEORGIA.

Annelids-------- - -------------------------- --------------- _ 40 Anticlinals defined------------------------------------ _____ 16 Artesian Well at OredelL- ------------------- ------------- ___ 161
Base Level of Erosion-- - ---- -------- - - --- - - -- _------ - -66, 67 .Bangor Limestone---- - -- -- ----- -- --- - - --- - - ---- ------ --- 29 Bartow County, Local Geology oL------ ----- _- ----- _. ---- _____ 99
Physical Features of.------------------------- 69 Ores (see Resources). Bathyuriscns _--- _--. - . --- ___ --- __ _: ______ - __ - ____ . __________ 40
Beanxite ____ - ---- - - ----- . -------- ------------------------214 Analyse;; ____ ------ ------------------------215, 222, 2.37 Alabama______ ___ __ _ - --- -- - - - -- -- - - -------- - - 234 Distribution in Georgia- ________________ . ________ . __ -226 Distrihution, Foreign ___________________ .. ____ ---- 220, 232 Knox Dolomite ____________ __ . __________________ ___ 224 Occurrence of_ _____________________________ _______ __224
Origin nf_ __________ -------------- ___ _______ __225, 234
Price oL ___--- ------ - - ---- -- ----- __ __- - - ___ --- - - - 239 Properties of_ _________ . ___________________________ - _214
Uses of_ ___,- - -------- - -- - ____ --------------221,239 Bibliography of Georgia Geology __ ___ - - __ --_- - -_- ___ --_--_-- _364 Biological Contrasts_____________________ . ___________________ 30
Black Shales (see Ghattanooga Black Shales). Bog Manganese Ore ___ -_- ___ - ________ .-- __________ - _____ ____ 192
Branner, J. c____ ____ ____ ________________ -------------- --.--222
Braunite ______________ . .------ - - -- _____ __- ----- - - - - ___ 192 Brick Pavem6llts ____ _______________________ ____________ ___ -216
Brown Sandstone-------------------------------------- ----273 Brown Iron Ore----------------- - -- - -- - --------------- ----150
Analyses l.' __ ________ ______ ____ ___ ___ ____ 172, 174
Clay horseil in _______ ~ ___ ..__________ _______ -- _-- _154
Deaton Ores--- --- - ---------------------156, 170,171 Depth of _______________________ ________________ 161 Distribution of __________ .. _____ ___________ - ____ -159 Koalin in ____ . __ . ______________ - __________ - __ - - _154

INDEX.

391

Rt wnh u re, Kinds oL - ------ --------~------- ------- 150 Kuo:x: <,Lomite ________________________ --- - - 152
Laf~y tt - - ------ -- - -- - - ----- - ---- - - --;------;1." 6
Melt\intot:phl - --- --- -- ----- - ----- -- --- .. ----- __ .16.R Ore-beuri1g P ottun.tion - __ ---- --- . ___ ____ __ __ __ 152
l'i rin of --- --- ---------- - -- -- ---- - - ---- .205 1-'l'ocl uct of ----. --- ------ - --. ---.--- __ _____ _J7 5 Sources of_ ______ __ ___________ _________________ . ----151
Sub-Carboniferous___ __ - ------- ________ .. 157, 169, 171 Thickness of_ ___ _ --- - -- - - - --------- . --- ______ . .... . 153
W 1rl ing f_ - - - - - --- ---- -- -- - --------- - - __ J.7'1J. Wa hill~ of --------------- ---- ----- - __ __ - -- - . .156
Caen Stone-------------------- - ---------- - -- - - _ _____ ..85, 285 Calciferous (see Knox Dolomite). Cambrian System _- _- - ____ - __.. _-- ____ ________________ _ ____ 34
Fossils _____ .. _____________________________________ .40
Shales (see Oostanaula). Cambro-Silurian Syt>teJD ______ ------------ --. ----------- 42 Carboniferous System ________ ------ ----- ___ ----------. ----- -51 Carnes' Mountain ____________ _____ .. ___ ____ . ____ _ __ -- -- ----- _61 Cartersville Fault_ __________ ______ ___ ___ ____ _------- - 2 ' 0, 84
Manganese and Iron ________ ________ - ------- - -----195 Caves _________ __ ___ ---- _________________ _44, 74, 75, 83, 105, 1,57
Changes of River Levels --. __ ----- ------------- ______ __ __ _65 Character of Streams ___ _ ______ . __ __ ------_--- --- - ---- - - . 64 Chattanooga Black Shale-
General Characters_------ ______ ., ____ 50 In Gordou County____________________ 110 In Whitfield County _________________ 117 In Catoosa County ______ _____________ 121 In Chattooga County______ . _________ .126
In Walker CountY----- - -- - - -------- 135 In Dade County_____________________ 142
Cl:rattooga County Local G eology _______ __ __ _______ - - ------~ - -123
Physical Features.. --- - -- - ----- --- - ---- - - -- --72 Ores (see Resources).

392.

GEOLOGICAL SURVEY OF GEORGIA.

Chazy (see Chickamauga). Chickamauga Series- .
General Character ..________ ---~ __ --_ - ___ .45
In Polk County--- ___ -------- __ ---------- -82 In Bartow CountY-------- ---- -- ---- - --- 107 In Murray County_ _____ ____ _-------- - -- 11~ In Whitfield County ____________________ :.l16 In Catoosa County ______________________ _120
In Chattooga County_______ --------------124 In Walker County_____________________ --131 In Dade County-- _______________________ 141 Chilhowie Series_---- ____________________________________ 35, 77 Clark, W. B. __ ----- .. _________________________._. ____________ 366
Clays __ -------------- ____ .. _________ -- _______________ - 276, 279 Analyses ______________________________ . __________ 281-288 Alluvial ____ ------ ____________________________________ 286 Disintegrated Shales __________________ ---=-- ______________ 283 Kaolin _____________________ -- ____ __________________ ..280 Residual ___________________ ______________ _ ____ -------282
Clinch Mountain Sandstone ______________ ____________ ------48, llo
Clinton Series (see Red Mountain). Coal (see also Coal Measures) _________________________________ 24 7
On Sand Mountain _________________ _------ ____________ .247 On Lookout Mountain ___ ____ ________ _______ - ---- ___ ---254
Analyses ---:----- - - - --- ------ - ----- -- - - ___ _258, 259 Coke -- - - ---- - _., __- - --- ----- __ --- _____ ___ _____ _258, 259 Mines ___ .. --- ------ - ---- ____ -- -- ------ ----- __ ___ _259 Coal Measures-
General Character__ __ _____ -- ------- ____ __ __ 52
In Chattooga County_------ -- ______________ _-127
Outliers of __ --------------------- ________ 128In Dade County _________ - - - _____________ _____ 143 In Floyd County--- - __ .. ___ ________ . ____ . ______ 9(} In Walker County _______ _______ _______ - .. ___ 136
Cohutta Mountain -------------- - ---- - - - ---------- 37, 62, 71, 75, ,College Farm, Soils oL ________ .. ___________________________ -11~

INDEX.

393

Conglomerate Ocoee - --- - - - -- --------- ---------- --- ------ - - 35 Conglomerates-------------------------- ----------35, 53, 54, 85 Contrasts, Lithological ------- _-- _-- _-- ____ -- _________________ 30 Connasauga Series (see Oostanaula). Continental Margins --- . ~- _- _-- _-- ___ - - .. ______ . ____________ .15 Coosa Shales. ------ ------- __ -- _-- ________________ ____ . ____ 29
Coosa Shales (see Oostanaula). Cotting's Report on Geology ____ --------_- ___ . ______________ .... 364 Cryolite ----- - ____ ---------- _-- - -- __________ .. _____________ 211
Dade County Local Geology- ---- ---- -- --------- __ _ ,. __ __ ......141
Physical Features.. ---------- --- ---- . --- --- - - 73 Ores (see Resources). Dade Coal Mines.. ____ - __ ---- _________________________________ 259
Dall, W. H ... --------------------------------- ___ .... 366,371 Date of Cave Making ___ --_-- ________________________________ 75
Deaton Series.. ---- ____ -------- ____________ ------. _____ .. -46, 83
Ores (see Brown Ore) . Decay of Limestone ---- --------- --------- --- - ------23, 44, 103: Depth of Rock _________ ---------- - ----------------10,22, 44, 82 Denudation, Enormous _________ ------ --------------69, 97, 128Depositon of Iron Ore (see Origin of). Degradation of Strata---------------------------------23, 25,26Destruction of RockR ______ -- _________________ .. ____________ ... 10 Devonian System ______ ------ __________ . ____________________ 50 Dip of Strata_ . ____________________________________________ .. 14-
Dislocation of Strata ____ -- ______________________ ----- __ .16, 181
Distribution of Ores (see Each Ore). Dolomite (see Limestone). Drumlin-like Mounds _________________________ -------------101
Dyestone Group (see Red Mountain).
Economic Resources __ ---- __________________________________ 147 Table of_ _________________________________ 149
Effects of Folding of Strata-------------------------- ________ 21 Effects of Rain on Strata ____ _ ______________________________ .9, 21 Elevation of Land _______________________ .. ____ . __ . ______ .. 11, 16-

:394

GEOLOGICAL SURVEY OF GEORGIA.

Elevation (see Altitudes). Elevation of Georgia __ - _--- __ --- __ ______ ___ __ __ ____ __ ____ __ . 67 Erosion, Depth of-_- __ --_--_- __- __ - _____ - __ __________ ____ ___ 25 Erosion of Lookout Valley ___ -- _ . - _-- _- __-- _- _____ __ _________ 25
Erosion, Enormous ------------------------------- - --59, 97, 128 Evolution of Northwest Georgia ___ __ --------------- . 55, 56 Etna Mines (see Brown Ore). Experiment Station Soils ______ ______________ --- - -- -- -- - -- - - .351 Extension of Gravels - _ -- - -------------- _- __ - ________ ___ _____ 97
Fault DefinedCartersville__________ ________ . ___ __. __________ 28 Cave Spring-- _________ __ . __ ________ . _____ ----20 Oostanaula ___ _ __ ___ _----- ___ .. ____ 37, 38, 88, 111 0 verthru sL __ ___ . . _.. . _____ . __ . __________ 19, 113
Reversed __ _ -- - --- --. --- - ------. ___ --. ___ .. 20 Rome ---------------~-- -- -- - 19, 28, 33, 87, 108 Saltville ------- --- -- --- --- -- -- 19, 28, 33, 87,108 Whitfield County ------------- __ ___ _ __ __38 Westboro ____ - . _-- ... __ - __ - ______ .. _ _. _ . ____ -134 Flagstone ----- - -- ---- - -- -- - -- --- __ __ _____________ _____ 273
Flatwoods ___________________ __________ :n, 52, 65, 68, 87, 96, 108
Floyd Shale Defined __ ___ . _________ . ___ _____________ __ ______ 52
In Floyd CountY-- - ---- - ----- - ----- - -------------96 In Chattooga County ___________________ _________ .127
In Gordon County------------ - ------- ---- _____ uo
In Catoosa County ______________________________ 131
In 'Valker County ---------------- --------- 135 Floyd County, Local Geology__ _ -------- - - -- ----- --- ______ 87
Physical Feature~ _ - -- ---- -- --- ------- ---- ---- 68 Ores (see Resources) . Folding of Strata ________________ __ ___ __________ ______ __17, 18
Fort Mountain ____ __ __ -------- - -- - ______ ----- - ---- - -------62 Fort Payne Chert Defined ____________ -- -- -- ------- - ----------51
In Polk County _ - - -------- __ _ ---- - - __ __ 86 In Floyd County_____ ___ __ ___ __ __ ___ ___ . __96

INDEX.

:395

uo :Fort Payne Chert in Gordon County ---- -- -------- - - - ~ ___ _
In Catoosa County ---- - - ------ - - -- - - - 110 In Chattooga-------------------------- - ---127 In Walker_____ ___ ___:_______ _______ __ ___ -,-135
lnDade------- -------- --------------------142 !Fossil _________ ___ . ____________ . ___________________ .13, 3_0, 52
Bones __ ___________ ___ - _________ __-~- ____________ _.. 107
Cambrian __ _----- --- --- ---- ------- ,___ --- - __ _40 Plants ______ -- - ---- - -- -- ---- - - ______ ------ ----- - ----146 Ore (see Red Ore) . "Fucoids---------------- - ----- - -- ____ ---------- - -------36,38 Furnaces, Iron. _____ __ ____ ___ ____ _ __ ________ _____ _. ________ 189
Gaps in Geological Series ___ ________ . ____ _____ _____ _________ -.59 ,-Geological Belts ____ ___ . _ -- __ -------- _______ --- ---- __14
Group - --- - -- - - - -- -- - -- - - - - -- - -- - - - ----- - - -- --- - 27 Structure._____ ____ _----- - --- _---- ---.---- ___ __ 8 Table _________ ___ ----------- _____________ ------29 'Gibbsite _______ -~------- ___________________ _ ___ __________ 212 Glaciated-like Rock.. ______________________ .. _________________ 89
Gordon County, Local Geology--- -- --- - --------------- -- ----- 108 Physical Features ----- - - __ - -------- ------- 70 Ores (see Resources).
-Gravels, Angular (see Knox Dolomite; see Ft. Payne Chert). ::: Water Worn (see Lafayette) .
Growth of Strata - - ---- - -------- . . . . _______ __ _--------- 11
~Halloysite and Analysis ___ ______ ______________ _ __ _____ _____ 212 Harris, G. D. __ ___ . ______ ____ ..__ . __ ____ ____ ____ ____ - ----- 366
"Hayes, C. W --------------------28, 32, 36, 38, 39, 44, 45,132,366 Hardi_n's Saltpetre Cave _________ _____ _________ _____ . . 74, 105, 107 Hematite ____________ .. __________ ______________________ -- .17 6 "Hillgard, E. W. ________ ________________________ __ ___ _327-328
1Iudson Serie~> (see Chickamauga) .
Igneous o]o,__.________ -------------- - ------------ -8
Incompleteness of Formations.. ------ - --- - - ------- - --------- -15 Indian Mountain __________ ____ ______ ___ _ __________ 27, 67, 77,79



396

GEOLOGICAL SURVEY OF GEORGIA.

Indian ]dounds ________ ----------------------------- - ------107 Insular Georgia_____ --- ___ - __________ ___________________ ____ 15 Iron-Limestone __ - --- _____ ----- __ -- ____ _____________ _46, 83, 157 Iron OreR-
(See Brown Ores)- _______________________________ 150
(See Red or Fossil Ore)-------------- - -- ______ ____ 176
Johnson, L. C. ____________________________________________ 316Joints-- __________ ______________ ___________________________ 43.
Keith, Arthur _______________ ____ . ________________ _______ __36
Kaolin (see Clay). Knox Dolomite Series-
General Character-- ____________ ________ 42' In Polk County __ ______________________ 78
In Floyd County . - - -- --------- ___ __ ___ 92 In Bartow County _____________ ________ 102: In Gordon County ____ --- ______________ 109
In ]durray County- --------------------112In Whitfield County ____ ______________ -116
In Catoosa CountY------------- - -------119 In Chattooga.County ___________ - ___ _- __ 123 In Walker County _________________ ___ -130
In Dade UountY----------- - -----------141 Sandstone _________ ____________________ 3~
Shale------------- - ------- - --------- - -39 Ladd's ]dountain ___ . ____________________________ ___ ____ -43, 104
Lafayette SeriesGeneral Characters ___________________________ 55
Grave~---------- - -------------------------55 -
Altitude of_ ___ . _______________________ --- - - 97
In Floyd County - ------------- - - - ------ - 97 In Bartow County -------------- - ------ - - - 107 In Gordon County -- -- --- - - - ---- --- - ----- __ _110 In Murray CountY -------- --- ----- - - - ----- 113In Whitfield County _______ .. ______ ________ -- _118
Absent_________ __ -------- -------- -----146

INDEX.

397

JLakeleffi---------------------------------------------------74 Langdon, D. W , __ ______ __ - - - ----- -- - - - - - - -- -------- - -366 Lula Lake ________ ---------'----- ___ --- ------ ___ . __ --- __ 73, 74
Lula Falls------------------ ---------------- --- --------67, 73 JLimestone ______ -------- ----------------------------8, 11,261
Analyses of _____ -- ______ ------ ________________ .263-271
Carboniferous._--- --- --. --- __ -- __ -~- --- __ . ________ 270 CementRock _____________________________ -------264
Character of_------------------------------- ______ .261 Chickamauga __________ ---------------------------- 268 Composition of_ __ __ __ __ _____ ___ --- -- --- __ _ ____ . _ _261
Decay - - --------- --- - ----- - - - - -------- ---- -~ - - 23 Distribution of.. ___ -------- ------------------------- 262 Dolomite __ ------- -------------------- --- _-- ____ .262 Hydraulic .... _____ -- ------------- ----. -- ------262, 264 Knox Dolomite----------------------- __________ ---365 Oostanaula.----- --------- - ------------ ___ . _______ . 262 Red Motmtaiu_ ----- ------ ---- ___ .. -------- _- _- ___ .270 Limonite _______________ -- ___ - --- ______________ .: ___________ 150. Lingulella _____________ .______ _________ _____ .. _____________ .40
Little, George ----------------------------- ____ 36, 37, 364, 365 Lithology____ __________________________________________ ___ 8
Lithological Contrasts ________ ----- - ________________________ 30 Loams ______ .. ______________ .. _______ ________________________ 26
Lookout Mountain Folds __________________________ ______ . . --- 18
Lookout tlandstone ---------------- -- --- --------- --------29 Lookout Valley, Origin oL ____ - -----------. _--------- _______ .25 Lower Silurian System ____ - ___ ---_--- ____ - __ --- _____________ .-42
Law of Survey--- ----------------------------------------368 Le Conte, ,Joseph ___ -- ___ -- _-------- __ --- __ ---- ________ - __ - 371 Loughridge, R. H .---- -- -. - -- ---------~-------- - ------ 365 Lyall, Sir Charles--- - ______ .- -- - -- ----- - - ---- -_---- ---- __ 371
Maclurea Limestone ____ ------ ______ --------------- -------46, 82 Manganese ________________ __ ----- -- - ---~--- - -- - - ____190
Analyses of Ores of_ _ --------- -~------ -----. ____192

398

GEOLOGICAL SURVEY OF GEORGIA.

Manganese, Cartersville Ore ________________ ______________ __ __ 191~ Distribution oL _____ ____ _________ - -__ ,_-- _______ - 200 Kinds of Ore------------~- ______ ---.--- ______ ----191 Occurrence oL __________________________________ 195 In Knox Dolomite __________ .. ________ ---------- __ 192 Origin of Deposits ___ _____________________________ 205
Uses oL-~------ - - ------------------------- ____ _190 'Vorkingsof____________________________________ _204 Manganite ___________ _________ ____________________________ _192
Margin of CobtiuenL ___ -- _----- ________ _______ ______________ .15 McCandless,J. M, ________ _ -- - ------- _________________ ___ :)67 McCutchen, A. R, _______ __ ------ _____________ ------32.,44, 365 McGee, W. J , __ ___ ______ __ -- -- ------- - ---- - -----3(:)5 371 Medina Series (se~ ~ed Mountain). Metamorphic Ores ______ ___________________ _ -- - - ____ - _____ --168
Rocks _____________________ ___________ ____ _______ __9
Schists ___ ------ ---------------- - ------ - - -- - 35 Metamorphism, Cause of_ ____ _____ __ _ - --- ------ - - --- -- --- - 84 Modern Formations ________________ ,')5, 57, 86, 97, 98, 107;.110, 146 Montevallo Shales- ___ - ____________ .. ________________ .. ________ 29
Mountain LimestonesGeneral Character_ ________ - __ - __ -- --- ____ 52
In Chattooga Count)'------ --- - ----------127 In Walker County ___ -- ------ - ------ 136 In Dade County_ .. _______ __-------------143 Mounds, Indian ___ - _____________________________ ___________ 107
Murray County, Local GeologY------ - ------ - ----------- ------.- --112 Physical Features------- - ---------- ________.__ _71 (See Resources).
Niagara Series (see Red Mountain).
Obelella ____ . _____ _... _________________ _____ - ___ - -- ________ 40 Ocoee Series ___________ . ____ _____ . ____________________ .. __ 34
Ochre Works.----- _________________________ ---------- __ .. 175 Olenellus- ____ -- ------ _:_ _- _____ - _- ___ -- .. ____ - -- __ - _- ______ 36 Olenoides----- ___________________________ - __ ---- _______ .38, 40

INDEX.

399

Oostanaula FaulL .... ----------------- - --.------ ----37, 38, -88, 89 Oostanaula Series-
General Characters--------------------- ____ 37 In Polk CountY------------------------- - 77 In Floyd County - -- --- - -- - - - ------ 87 ,In Bartow County --- -- ---- ---- ------- - --- - 99 In Gordon County------ -------------- . 108 In Murray Connty ______ ---------- .... 112 ___ __ _ In Whitfield County ____ ----- ______ .... ____ ---115 In Catoosa County _____ . --- _________ . __ .... 119 In Chattooga County ...... _______ ------------123 In Walker County_------_----- - ________ .... 139 Origin of Coosa Valley ____ - __ ---------.--- _________________ 24 Limestones .. -- .. --_ .. ---- .- -- ... -- .... - ...... - ____________ 11 Lookout Valley_------------------ ________ ....... 24, 25 Ridges---- - - -- ---- ------ -.. - - ----- -- ........ ________ 22 Valleys.. -- - - ------- - -------------- - - --- --- __ __ 24. Ordovician System--- -- ----- - ------- ---- ------- ______ 42 Ores, Aluminium (see Aluminum).
Iron (see Brown Ore). Iron ( see Red Ore ) . Manganese ( see Manganese Ores). Oscillations of Land __ -- .... -.... - . - .. -- _- .. - .. .. .. _.. - ___ .. ___________ 11 Oxmore Sandstones _____ .. _--_ . - __ - .. _- . ______________ .. _.. _____ 52
Paleozoic Group, Thickness of.. _____________________________ 31, 52 Soils _________ _____ -------------------- ___________ 309 Submergence.. ___ . __________________ .. ______________ 1.5
Period of Folding.... ____ .. __ _______________________ .... ________ 58
Physical Features, GeneraL-----_ .. -- ____ .. -- _____,_ .. __________ 60
Of Streams------------------------------. 64 (See Counties)_ .______ .. _______________ .. _67, 73
Polk County, Local GeologY---------------------------------- 77 Physical Features-- __ Y ______________________ . __ 67
Ores (see Resources).
Potsdam Series.------------------------------------------- 2(}

400

GEOLOGICAL SURVEY OF GEORGIA.

Protection of Knox Ridges ___ --- __ -- ______ - _________________ 81
Progress of the Survey_--------_ .. ---- __ ---- __________ R64, .371 Psilomelane ____ -- __ -- __ - ___ . ___________ __ . _____________ --192
Ptychoparea. _____ -------------- - -~----- - ------ -----------40 P y.coht He----- _------ - __ - - ---- __ __ -- - - -- ----- - - - --- -- - - - l. 91
Quartzite, Chilhowie ____ . _________ _------------ ------- -36, 77 Ocoee ___ - - ----- - - - ---- ---- ---- -- - ---~- - - -- -- - - 3~ Indian .MountaitL _--- __ -- _- --- _- ----- __ -- _- ______ 272

Red or ''Fossil" Iron OreAnalyseS---------------- ____ --- __ 187 Characters_ - --_- -- __ ..- . ----- - _____ 176 Distribution _____ -- _______ -- ------ _181 Hematite ______ . ________ -. ---- _-- _17 6 Mining oL- ______________________ 184
Occurrence oL --------------- 177 Source IlL - ----- --------- ----- -) 77 Thickness oL __ --- - ---- -- ------ . 183 Red Mountain SeriesGeneral Character----- ------- - ------ -48 In Polk County ______________ ----------86 In Floyd County------------- ___ _______ 94 In Gordon County ______ ---- ____ - - -----110 In .Murray County _____________________ 113
In Whitfield County ______ --------------117 In Catoosa County----- ____ -- - ---------121 In Chattooga County ---- -- __ _ ---- -- ---124 In Walker County ---- ---- -- ----------132 In Dade County ______ --- - ------ - --- - ___42 Recent Formations ______ ..__ .. ___ __ ___ ___ ____________ .. ___ 55, 146
Regional Growth of Formations ______________ -----------------15 Resaca Fault . ____ . _____________ ______ . ___________________ -111
Residual Earths, Numerous References___- ____ .. ________ _____ ____ Ridges, Origin of'_- . ___________:_ -- ---- _--- __- -- _______ -- ___ 22
Ripple Marks--- - ------ - --- - --- - ______ __ --------------- - --38

iNb:EX:.

401

River Channels, Size of------ __ -_-_--- ______________ .. ____ ____ 65 Rivers, Character of- __ ----- ...----_- _______ . _______________ __64
Roads Relation of Ro&ds to (;feologicalund Physicnl l!' nt ure -----290
_J11wacter of-- --- -- ---------------- ---------- ----290 Uos't of Bad .. ----- - -- - -- --- --- ---- -- --- -- -- - -------2H8
11 Ditf te.n.t Geologicul Formalious-- -------- - -----291, 2M
c;.l>oci v ~- ue :Bad------------------------------- - ----'208
Good in'Emope---- --- --- ------------ -- -- ----- - -- 300
Locatio.ns of------ ---------- ---------- - -----------2fl0
Source of R fl.<~ 1atelinL- -- _____ ___ --- - ___ __ __ ___ ___ 2f.I O
ockma~t lates- --------- ------------- -- -- -- -- --44, 81, 84, 275 HockwO(lCl , al'iea . _----- ------ - - -- ---- 7 - - -- -- -- -------------29 E k Oec.tlY---- - - ------- --- -- -- --- -- --- - -- -- --- - - -- - - --10, 82
(See Saltville Fault.) Rome FaulL-----_---- . ------ .. _- ---.---. _.- ___ - ___________ .. 28
'Rome n.ndstoJl e- - -- -------- --- -- -- - ------- -- -- -- ---- -- ____39

'nlford James- -- -- - -- ------- ------ -- -- ---40, 42 43, 45, 48, 3()6 nhJ)etre Cnve.. -. - --- - - ------ ----- --- -- --- --------- --- __ 74 r3nlnvill ifl.UIL - - --- -- - - -- - --- -- -~ -- -- .. - - ------- - ---- -- - 28
Stutdsj;OOGS------ -- -------- --------------- --- --- -- -- -35, 49
hilhowi ------- -- -- -- ---- - --- ---------- - 6 272
Oo~:~,l nsures------ - --- - -- ----- --- ------ -- ---- - --2'i!l
Oosto.ut~llhL -- -- --- --- --- --- -- -- - - --------------:l72 Hed M ountn-in ___ - ---- -- - - --- ------- - -- ----- -- -~- 272 Sub- 'arbouiferons____ ------------------------ ___ 27' ~ plitlw ~- - ----- - --- -- - ------ ------ ---- -- -- --- --- - - --- ___ 25
SEll , tuUb tinn - --- - -- ---- ---- -- ---------- - -- ----- -- ---- 5(i Carbouifeous__ __-- - - - ----- -- - -- --- -- - ---- -- --- /)
Dev:ouinn - --- ---- - -- - -------- - - ----- ------ --- -- - - - -- 58 Ordovi iuu ------ -------------------- - ------------ i Pliocene_------ ----- -- -- - _-- - --- - - ---- - --- __ ------ - -59 l;;ilmiun_____ --- -- ---- -- - ------ --. __--- ------ f\7
Sedimentruy Roclcs--- ------ ___-------- --- --- ------ ---
(26)


402

GEOLOGICAL SURVEY OF GEORGiA.

Silurian System.-----______ ___ -- ---------- -------- _------- 48 Sinks__________________ ---------------------------------- 74 Slates __________________________________ ---- ___ -- ____ 35, 275
Slickensides ________________ . _ _- _______ .- __ .- - __-- ___ - __ 21, 89
Slide Rock ______ -------- __________ --- _- ------------- _____ .89
Smith, E. A,_ ---------------------------32, 36, 38, 39, 44, 366 Soils ____________________________ ------------ ------------309
Accumulation of food oL __________ . ___ -- _____ -. --'- ______ 31S
Ammonia Salts in ______ - ----------- -------------- -325 AlluviaL Formations of_--- _______ . _____ --_ - - __ -- ___ . _____ 318
Analyses from Crystalline Rocks ____ ---- ------ ______ 355, 357 Analyses of College Farm .. ---- _----- __ .-- _- _-' _________ .362 Analyses of Experimental Station------ _______________ 355, 357 Analyses of Paleozoic___ __________________________ 331, 348 Analyses of, Value oL __________________________ c _______ -325 Calcareous _______ - _______ - ____________________ :.. ____ -'-- 322
Character of.:.--------_-----_.----- ___ ------. _____ .358, 360
Character of Archrean __ - ---- --- - ---- --- ------ ---Character of Paleozoic _______ --- _________ -~ _~- _________ .. 312
Chemical Relation of Paleozoic ______ --------- ____________ 329 Chlorine in __________________________________________ .326
Clay-.--- ____________________________ ~---- _________ ... 312
College Farm ____ - _____________ --~--- ____ ------------ __ 362 Color of-- ___ - __________ . ______ .. ______________________ . 312 Constituents of Plant Food ____________ ~ __________________ 323 Consumption of Plant Food by Corn-~----------- -------327 Cousumption of Plant Food by Cotton ___________________ .327 Consumption of Plant Food by Wheat-. ______ -~ __________ .327 Corn, Salts in __-----------------_. ___ ~_~.- _~.- ________ 327 Cotton, Salts in _____________ --------------------------327 Creep------- ---------------- ____________ ----- __ 317 Depth of Residual Earth _________________________________ 315
Diminishing Solubility of Plaut Food _____ ----~-----------319 Effects of Organic Matter on __________________ -----~-----318 Effects of Plant Food on ___________________________ . _____ 325
Estimating Value ot__ __ ----------------------- ------__325
~

7

INDEX.

403

Soils, Experiment Stations._~ _____ ---_-------------'-----.:.--- . 351 Ferric Oxide in ______________ . __ -- ___ - - _- ---- __ -- ___ -- .826
Ferruginous ____ --- - -------.---:--------------------. ___ 322 Fixing of Plant Food --- ------- - ----- - ----"------ - 324 Formation of____ - .___ --- _--- - ----- --- --- ---- _- - -- __ _312 Formation of AlluviaL_-- __ -- __ - --- . --- --- - -- ________ 318 Formation of Archrean. _____ --- __ -- ___ -- __ - --- _____ -- _. 317
Formation of ClaY--------------------, - --------- ______ 317
Formation of 'r Jl --- ---- - - -- -- -- - -- -- -- - - __ 817
Formation of L'ittl. t,,')ue____ ------ ---- ------- ______ ;314, 317 Formation of ResiduaL ... - ___ -_- -- -- - -. ______ _ -~ _____ . 314
Formation of Sandy _____ - - - -- - -- - ---- - ----------- - --- - 317 Formation of Shale________ ------------ ------ -------- 817 Geological Relation of Archrean - -- ----- - ----- ___ __351
Of Chickamauga.---_ - ___ ---__________ 342
Of Coal Measures ---- - - - -- -- ------ 347 Of Floyd _--- - - - ------- - ----- - - - _345 Of Fort Payne- ----- - -- - -------- 34.5 Of Knox. _____ -------------------- -.337 'Of Lafayette -- - - - - --------- __ __ 347 Of Modern ___ ------~-- __ -' __________ .347 Of Mountain Limestone------ _________ 346 Of Oostanaula______ -- _________ ______ .329
Of Paleozoic ------- - - - - - - ---- 329 Of Red Mountain ________ _____________ 344
Of Sub-Carboniferous.. _- ________ _____ .345 Geology of Experimental Station ________________________ .351 Geology of Coll~geFa1m ____ ---------------- -------------_,362 Heat related to Physical Structure ____ .. ___________ _ _____ .322 Kinds of_ _____________ -' ________ _____ ________________ 321 Lime Necessary in. ____________________________________ . . 325 arly---- ___ --- ________________________ __ ______________ 322 Moisture in ______________ ____________________________ 326
Moisture R'elated to Physical Structure __ --- ---- - ------ 322 Origin of Materials of - - ------ - ---- ____ -- --- _ 314
Organic Matter in---~---~-_-----~- ____ -~-7 ----- ____ . __ .318

404

GEOLOGICAL SURVEY OF GEORGIA.

Soils, Organic Origin of Limestones ____________ -_---- ___ -- ____ 316
Archooan ------- -------------------- ------ - - ___ _351 Plant Food, Sources of_ ___ ------------------------ _____ 315 Plant Food, Fixing of__._---- -------- ---- ________ --- 324 Plant Food Nece~arY------------------------------~---323 Plaut Growth ____ .. __ - __ --------_- __ ---------- ________ 361 Phosphate Necessary--_- __ -- :_--- ______ ------ ___________ 325
Potash Necessary ___ ------- ---- - - ___ ------- - - ---- __ -- _325 Physical Conditions ___ ___ ----- -- --- --------~ -- ---- -326 Physical Properties ____ ------------ __ -------- __________ 321
Relations of Physical Features of ------- ------------ -361 SandY------ - -----------------------------------317, 321 Shaly _________ --- _----- ------ __ -~-- -- - - ____________ 317 Sod~ in ________________________ _____________________ 326
Sulphuric Acid, iu_- .. _--- _-- ------ __ -- ---- _- -- ________ 326 Sources of Plant Food, in ____________________ - ________ .315
Soluble Minerals, in.---------- ______ ---- _________ 358, 360
Structures of Archooan - ------ ---- ------ ------ - - - ---- 353 Table of Geological Formations, in Relation to _____________ 311 Value of Analysis ... ---------_---_--~----- ___ ~ ___ . ____ 325 Value of Experiment Station __ ______ ------- - - - --- - 360 Spencer's Report on South Georgia___ - ______ -- __ -- ____________ 3(:)5
Spencer's Report along M. & B. Railway ----------------------36.") Springs-- ___ - __ --------------_-- ___ ------------ __________ 83 Squires, Joseph---------. _________ --- _. __ - --- _______________ 33 Stalactites _______ - ___ - ___ - ______________ - --- ______________ 105
Stevenson, J. J ---------------- --------------- ------ _ 28 Streams, Character of_ ____________________ - _- _______________ 64 Subsidence of Land ___ . ___________________ - ________________ 11
Sub-Carboniferous Series-
General Characters- ---- ---- -- - - - 51 In Polk County _______ __ _____________ 86
In Floyd CountY-------------------- 96 In Gordon County __ ------ ___________ 110
In Whitfield CountY-----------------117
In Catoosa County ------ - --- ------122

INDEX.

405

Sub-Carboniferous Serit>sChattooga County------------------ .126 In Walker County------- -~- - --- --- I3fi In Dade CountY------- - ------------142
Submergence, Paleozoic____ _----------------------- ____ I5 Submergence of Georgia -- --------- - --- ----------- - - - - 26, 59 Succession of Unlike Materials- ----- -------- - - - ------- - - --- I2 Synclinals Defined ____ ------------- - ----------- ___----- ___ I6
Table of Altitudes_________ ---- - - -- - - --------- - --- - - - - --- 76 Of Economic resources- -- ~---- - - - - - ---- ---------- Geological Formations -------------------------- -27, 29 Of Soils __ ---- _- -- -- -- - - - __ _------------ -----------
Terraces. ---_ - - - ---- ------- ___ ---------_ - - -___ _____ ____ ___ 98 Terrestrial Movements- _____ .. __ - - - ----_----------------- __ 11 Thickness of Paleozoic Group ____________________________ 3I, 32
Of Formations (see Each Series.) (Also see Under Soils.) Timbers.---- .. --------_---_- --- _-- .. _-- __ -- ---- ____ - -- - ----289 Trenton Series (see Chickamauga).
Unr,onformities _______ -- _.... ___ .. ___________ ...... _______ _------ II
Valley11, Origin of_ _________________ __ _________ __ ______ ____ 24 Value of Fossils___ - ___ .... --_ .. _____ - ___ .. ____________________ 30
Walcott, C. D, ____ :_ _______~--'-- - 36, 38, 40, 4I, 366, 367 Walker County, Local eology- ----- - - ------ ------- - ----- ----130
Physical Fentur ------ ---- --- ______ :_, _____ 73 Ores (see Re ource ). Waterpowers -------- ..... ------ .. - ----------------------289 Watershed of Coosa Valley--------- - -- - --- - --------------- 71 Weisner Quartzite--- --------------------------------- 31) Wells in Knox Series- ------- - --- - - ------ - - - ---- - - - --- --- 82 Willet, J. E, ______ ___ _ __ .. ______________________________367
White, H. C.. ..: ____ ________ __ __ _ -- -- ---- --- -- ------~-- --367

406

GEOLOGICAL SURVEY OF GEORGIA.

Whitfield County, Local Geology---- ----- --- ----- ------ ------115 Physical Features __ -- ---- - --- -- ----------. 71 Ores (see Resources).
Zinc in Brown Ore.- ------------- - ----- ---- -- - ---- --------172

Atlanta, July 15th, 1893.

GEOLOGICAL SURVEY OF GEORGIA.

J. W. SPENCER, Ph. D., F. G. S., STAT E GEOLOG I ST.

LEGEND

(/)

c \coal Measures

:J
a0 w :

Mountain Cm Limestone

zl.L CJ Floyd Shale

0am:: Cp FT.Payne Chert

<u (

1--t:t-- Cha11anooga Blac'k Shale

R Red Mountain

z ~ " ChicKamauga

>[

3 ch
Ui f--- -

Limestone & Slate

0oa:

~ o

~ Knox
1 - -'' - - - - '

Dolomite

o~ _ J

Oostanaula

?Mt Metamorphic

------Faults Scale
? rW 3 4 W

T Miles

250, ft , Contol!rs above tide.

LOOKOUT Mt.

0 SG<te

1

2

" --1-J N iles

"V;r i .,.Cal 0 _,..,, rooo Feel .

as oYorkville

..
..