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Comparative views of the composition of the soils, limestones, clays, marls, &c., &c., of the several geological formations of Kentucky : as shown by the chemical analyses published in the several reports of the geological survey of the state, with remarks on their characters and practical uses / by Robert Peter.
Comparative views of the composition of the soils, limestones, clays, marls, &c., &c., of the several geological formations of Kentucky : as shown by the chemical analyses published in the several reports of the geological survey of the state, with remarks on their characters and practical uses / by Robert Peter. Peter, Robert, 1805-1894. 400dpi TIFF G4 page images University of Kentucky, Electronic Information Access & Management Center Lexington, Kentucky 2002 b97-20-37305884 Electronic reproduction. 2002. (Beyond the shelf, serving historic Kentuckiana through virtual access (IMLS LG-03-02-0012-02) ; These pages may be freely searched and displayed. Permission must be received for subsequent distribution in print or electronically. Comparative views of the composition of the soils, limestones, clays, marls, &c., &c., of the several geological formations of Kentucky : as shown by the chemical analyses published in the several reports of the geological survey of the state, with remarks on their characters and practical uses / by Robert Peter. Peter, Robert, 1805-1894. Geological Survey of Kentucky, Frankfort, Ky. : 1883. 62 p. ; 26 cm. Coleman Microfilm. Atlanta, Ga. : SOLINET, 1997. 1 microfilm reel ; 35 mm. (SOLINET/ASERL Cooperative Microfilming Project (NEH PS-21089) ; SOL MN06745.09 KUK) Printing Master B97-20. IMLS This electronic text file was created by Optical Character Recognition (OCR). No corrections have been made to the OCR-ed text and no editing has been done to the content of the original document. Encoding has been done through an automated process using the recommendations for Level 1 of the TEI in Libraries Guidelines. Digital page images are linked to the text file. Geology Kentucky. In the Kentucky Geological Survey Publication, Ser. 6, v. 1 (Frankfort, 1923), Geological Research in Kentucky by Willard Rouse Jillson, the author cites the inclusion of 1 map with Robert Peter's publication, Comparative Views of the Composition of the Soils, Limestones, Clays, Marls, &tc., of the Several Geological Formations of Kentucky, as Shown by the Chemical Analyses Published in the Several Reports of the Geological Survey of the State... (1883). Four copies at this publication at the University of Kentucky do not include a map. Copies of this publication at the U. S. Geological Survey Library and the University of Chicago Library similarly lack this map. Adelaide Hasse in Index of Economic Material in Documents of the States of the United States, Kentucky 1792-1904, Washington, D.C.: Carnegie Institution of Washington, 1910, presents a nearly comprehensive overview of the KGS publications. Hasse does not include the map in her description of this publication. The text makes no reference to map. GEOLOGICAL SURVEY OF KENTUCKY. JOHN R. PROCTER, DIRECTOP.. COMPARATIVE VIEWS OF THE COMPOSITION OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C., &C., OF THE SEVERAL GEOLOGICAL FORMATIONS OF KENTUCKY, AS SHOWN BY THE CHEMICAL ANALYSES PUBLISHED IN THE SEVERAL REPORTS OF THE GEOLOGICAL SURVEY OF THE STATE. WITH REMARKS ON THEIR CHARACTERS AND PRACTICAL USES. BY ROBERT PETER, M. D., CHEMIST TO KENTUCKY GEOLOGICAL SURVEY, STATE CHlMT, PROVES8OR OF PHYICSc AND CREMISTRY IN KErNTUCKY STATS COLLEGE, &C. &C 1883. STt-ROTYPPD FOR THE SURVEV BY MAJOR, JOHNSTON & BARRYtt, VYOAN PRESs, "ANmupoRT, KY. This page in the original text is blank. INTRODUCTORY LETTER. LABORATORY OF KENTUCKY GEOLOGICAL SURVEY AND OF KENTUCKY STATE COLLEGE, LEXINGTON, KY., April, 1883. MR. JOHN R. PROCTER, Director of Kentuckv Geological Survey, &C., DEAR SIR: I herewith send vou such comparative views of the composition of the Soils, Limestones, Clays, Marls. &c., of Kentucky as I have been able to obtain from the various characteristic specimens which have been analyzed in this laboratory during the progress of our Geological Survey, from its commencement in i854, under the late Dr. D. D. Owen, down to the time of the latest published report of the work of the Survey. Yours, respectfully, ROB'T PETER. This page in the original text is blank. A COMPARATIVE VIEW OF THE SOILS ON THE VARIOUS GEOLOGICAL FORMATIONS OF KENTUCKY. In the study of Kentucky soils, and the numerous chemical analyses which have been made of them during the progress of the Geological Survey of the State, some facts of interest have been ascertained. That all soils have been primarily produced by the disinte- gration of rock strata is now universally admitted. But, as the debris of rocks is continually transported, by water and other agencies, from higher to lower levels, and as, during the so-called glacial epochs of geological history, the bodies of ice, which covered a great portion of our northern hemisphere, caused the transfer of an immense amount of these soil mate- rials, few localities present any large area of soil which has been formed where it is at present found by the decomposition of the rock strata in place. Kentucky is quite exceptional in this respect, as compared with the extensive regions to the north and west of our State. Ilhe valley of the Ohio river seems to have been the limit beyond which could not be carried the great mass of mixed materials-clay, sand, gravel, and bowlders of all sizes-de- rived generally from rocks in place in the far Northwest, which cover the surface on this whole vast territory, so that the superficial deposit which constitutes the soil generally bears no relationship to the rock strata beneath. Most of the soils of Kentucky have been formed from the rock strata of their immediate vicinity, being what are termed sedentaiy soils, and hence generally show a relationship in composition to the geological formations on which they rest, except such of them found in the valleys and low grounds of the rivers and streams, made up of more recently transported materials, which come under the name of alluvial soils. COMPARATIVE VIEWS OF THE COMPOSITION Kentucky is somewhat peculiar in another important circum- stance. The- superficial rocks from which her soils were pro- duced seem, with very few exceptions, as in the case of the coarse sandstones and conglomerate rocks of our coal-meas- ure strata, to have been primarily deposited and formed under the waters of a primeval ocean, at such a distance from the shores, and under such circumstances, as that naone but earthy or sandy materials in the finest state of division, entered into their composition, and large relative proportions of linme, mag- nesia, clay, phosphates, &c., are found in them. Pebbles, gravel, coarse sand, or fragments of rock are rarely present, except in some of the soils of the coal-measures. In most cases, in the large number of soils analyses which have been made of Kentucky soils during the progress of the Geological Survey, the dry earth passed wholly through a sieve having sixty-four meshes to the centimeter square; and, after this fine earth had been submitted to the solvent action of acids. the remaining " sand and insoluble silicates " were fine enough to pass through a fine sieve having about i,6oo meshes to the centimeter square-finer than ordinary bolting-cloth. In- deed, this silicious residue of our best soils is so fine that it is not generally recognized as sand, and although it is readily permeated by water, it presents some of the adhesive and absorptive properties of clay. Sand, so-called, is not to be found in the beds of the local streams where this soil prevails, and building sand must be imported. MANY CONDITIONS MUST CONCUR TO GIVE FERTILITY TO SOILS. I. Meteor-ological.-The climate, as to temperature, amount of rain-fall, &c., &c., presents important conditions essential to fertility. 2. Locafion.-Land at the bottom of a slope receives the washings and finer, richer materials from the uplands. It is well known that the atmospheric and soil waters, passing through continually, carry these fertilizing materials to the lower levels. The upper slopes are thus continually leached and impoverished, while, as is sometimes observed in our own 6 OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. State, the soil on the high level summits of hills is richer than that of the inclined valleys which drain their flanks. 3. Drainage.-No soil sodden with water can be productive of crops, however rich it may be in the elements of fertility. Kentucky is peculiarly fortunate in the fact that the great body of her soils are naturally drained. This is especially the case in the so-called - Blue Gi:.vs" soil, which, on sonim- what elevated table-land, is underlaid by limestone containling numerous crevices and caverns, which carry off the surplus water. But in some few localities, especially where the black slate formation prevails, the disintegration of which produces a tough clay very retentive of water, the injurious effects of too much water are evident. The soil may be found to be quite rich in the elements of plant food, but is not correspond- ingly productive for want of drainage. No better example of this can be given than that of a soil in Wayne county, based on the Sub-carboniferous Limestone formation, collected by the late Dr. Owen, and analyzed by the present writer in I856 (see Rept. Ky. Geol. Surv., 0. S., vol. 2, p. 273), which has the chemical composition of quite a rich soil, and is almost black because of its more than 21 per cent. of organic and volatile matters, but which was unpro- ductive for -want of draining and access of air -in the lan- guage of Dr. Owen, who added that with the aid of lime and a proper system of drainage, " I venture to predict it will become one of the most productive soils in the State." E'xtensive experience in England, and in the older settled regions of this country, has demonstrated the great' utility of underdraining the soil. Without attempting to describe the best methods of underdraining land, we will briefly state some of its benefits: I. In allowing the excess of water to escape continually, it not only removes this one cause of ster- ility, but tends to increase the porosity of the soil and the area through which the roots of plants may spread and obtain nourishment. 2. Because the body of the soil, during the growing season, is constantly colder than the superincumbent atmosphere, a current of cold air is continually flowing out of 7 COMPARATIVE VIEWS OF THE COMPOSITION the open mouths of the drain pipes, which is supplied by warmer air from above. This continued slow circulation of air through the cool soil not only causes the drained soil to become earlier warmed in the spring than the undrained soil, but brings to the growing vegetation a constant supply of the gases and vapors of the atmosphere which are essential to plant growth. The warm air, full of vapor of water, also deposits in the soil a considerable amount of water, which is condensed on passing through the colder soil; so that the underdrained soil does not suffer so much from droughts as the undrained. 3. The -abundant supply of air also favors those chemical changes of decomposition and recomposition by which the elements of fertility are brought into an available condition for the nourishment of plants. 4. Physical conditions.-The soil, to be fertile, must be in a state of fine division; coarse sand, gravel, or fragments of rock give little or no plant nourishment, and are usually ex- cluded, by all agricultural chemists, from their estimate of the value of a soil. The "fine earth " only is taken into account or analyzed. Thus, in the annexed table of soil averages, the conglomerate soils, which contain an average of 20.7 per cent. of gravel or pebbles, must have their estimated value (based on the analyses of their "efine earth ') discounted in this proportion. So, in the comparison of our rich "Blue Grass" soil with the very rich volcanic soil of Auvergne (see tables), a discount of i6 per cent. must be made from the latter for the same reason. Moreover, as a large proportion of the food of plants is derived from the atmosphere directly or indirectly, no soil, however rich it may be, can be very productive unless it is in a porous condition. On this fact, fully demonstrated by long experience, are based many of the practices of the husband- man in stirring, loosening, and cultivating the soil, especially during the growing season. 5. Chemicalcondizions.-Soils, to be fertile. must contain clay and fine sand, mixed in such proportions as that, while readily permeable by water, they may yet be, to a certain degree, 8. OF TH1E SOILS, LIMESTONES, CLAYS, MARtS, &C. adhesive. Pure sand and pure clay do not offer favorable con- ditions for vegetable growth; such a mixture of them as forms what is called a loam soil is generally considered the best. Fertile soils must also contain a certain proportion of organic matters, known generally by the name of humus, a mixture of substances derived from the decay of vegetable and animal matters, which gives the dark color to the soil as compared with the subsoil and the almost black hue to the rich garden mould. Humus makes the soil more light and porous, and possesses the power of absorbing the gases and vapors of the atmosphere, water, and dissolved natural fertilizers in a higher degree than any other ingredient of the soil. Undergoing a gradual oxidation, it furnishes carbonic acid, nitrogen com- pounds, and water, and by the ozone it forms during this pro- cess, favors the production of nitrogen compounds from the atmospheric elements. It holds ammonia, potash, phosphates, &c., against the leaching action of the atmospheric waters, yielding them readily to the rootlets of plants, and, by the acids it produces, in its ulterior state of decomposition. it aids in dissolving the essential mineral elements of the soil, mak- ing them available for plant food. It has been the fashion, in recent times, to underrate the value of humus in the soil, blindly following the teachings of Liebig. who gave too exclusive importance to the mineral ele- ments of fertility; but practical experience is corroborated by scientific investigation in giving a high value to humus as an ingredient of a fertile soil. "The latest conclusions of agri- cultural chemists are, that the excess of nitrogen in the crop over that contained in the soil is caused by the action, on the atmospheric elements, of the carbonaceous matters of the soil" (the humus).-Quoted from article ", TERRES ARA1aLES in WVur/z's Dictionuaire de C(emie, &c. In this connection we are tempted to quote from a recent publication of Peter Henderson, of New York, one of the most experienced and enlightened gardeners in the country, the results of his observations and practical experiments. After stating that the concentrated commercial fertilizers "will not 9 COMPARATIVE VIEWS OF THE COMPOSITION do" for any,great length of time to maintain fertility without the aid of stable manure, or some other meatns of improving what he terms the i' physical condition of the soil," he states: "hence experienced market gardeners near New York rotate their fields." Of twenty acres they keep five in grain, clover, and grass, " to be broken up successively every second or third year, so as to get the land in the condition that nothing else but rotted, pulverized sod will accomplish." (Humus.) "This is done where the land is worth five hundred dollars per acre. Experience having proved that with one quarter of the lanid resting under grass more profit can be got than if the whole were under culture." And this in the region where they habitually apply several hundred dollars' worth of commer- cial fertilizers to the acre per annum. In our newer country, where land is cheap, too little atten- tion is paid to fallow and rotation of crops, which both may serve to renew the humus which has been removed in the cul- tivation of the hoed crops. Fallow, or allowing the land to rest, need not be a "naked fallow," or letting it rest with no other crop but weeds, but could more profitably be a "Kwreen fallow," combined with rotation when clover or grass are cul- tivated, to be fed to stock, and subsequently plowed under to increase the amount of humus and otherwise improve the soil. And when small grain of any kind is raised in the rotation, the straw, instead of being burnt up out of the way of the farmer, could be more profitably used on the English plan. il a so-called straw-yard, where it is fed to stock and trampled into valuable manure, to be hauled to the fields in the early spring. It is now a well-established fact that cultivated soils require constant renewal of their elements of fertility, especially wvhen the crops are habitually removed, and no retUrn of manures are made to the soil. How most economically to effect this renewal is a practical question with most farmers, and one of great interest to the agricultural chemist. Besides the humus and certain other atmospheric elements above mentioned, certain other ingredients, called the mineral IO OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. elements of fertility, are equally indispensable to the fertility of the soil and to vegetable growth. These are phosphoric acid, potash, lime, magnesia, sulphur, chlorine, iron, and oth- ers, in such a state of combination as to be available for plant nourishment. Of these, all are alike essential as necessary elements in the composition of the vegetable. Yet, as some of them are found in very small proportions in soils, and are habitually carried off in the crops, such as the phosphoric acid and potash, the practical agriculturist holds these as the most essential, knowv- ing that the other essential elements of the soil are usually present in it in inexhaustible quantities, or are continuously supplied from the atmosphere. Hence the value of a com- mercial fertilizer, in renovating an exhausted soil, depends mainly on its relative quantities of available phosphoric acid, of potash, and of nitrogen compounds, especially, also, because these ingredients only will bear the cost of transportation to any great distance, and the others are frequently to be found near the farm. The farner who consumes most of his products at home has usually little need of any fertilizers but those which are furnished by his stables, compost heaps, or cess-pools, properly utilized; or by a judicious rotation of crops and feeding of his stock on his fields. But the commercial farmer, whether he cultivates that most exhausting and damaging crop, tobacco, or annually exports his cotton, hemp, potatoes, corn, or other grain, or simply sells his live stock raised on the farm, corres- pondinigly robs his soil of its essential elements of fertility, and, especially if he does not rotate his crops, must resort to commercial fertilizers to maintain its productiveness. The nature and quantity of these will depend on the composition of his soil and the character of his products sold off the farm but available phosphates, compounds of potash, and nitrogen compounds are their most valuable ingredients. Marls, when near at hand, may be advantageously employed, in quantity, to modify the physical character of soils, and to supply lime when deficient, and potash and phosphates in some cases. I I 12 COMPARATIVE VIEWS OF THE COMPOSITION Lime, ground or burnt and slacked, proves useful also on some soils, especially when, like the blue limestone it contains notable proportions of phosphates, potash, &c.; but both of these will not bear long transportation. Although the clay and the sand of the soil are not actually elements of plant food, yet they, in proper mixture, are essen- tial in furnishing the medium in and by which they obtain nourishment and growth, while the iron oxide which enters into the composition of the vegetable is almost always pres- ent in superabundance in the soil. The oxide of iron aids essentially in facilitating decomposition of organic matters, in ,the formation of fertilizing nitrogen compounds and by its great absorptive power. It is doubted by most agricultural chemists whether silica (the material of sand) is an essential article of plant food; yet it is present in notable quantity in all plants, especially in those of the family of grasses, and in the form of sand is necessary.to the porous structure of soil. WHAT IS THE CHEMICAL COMPOSITION OF A FERTILE So011 This question may be answered by reference to the ap- pended Tables. (See Sumrmary of the Averages of the Ken- tucky Soils fromt Different Geological Formations, 6&c.) Thle composition represented by the mean of the averages of the 234 Kentucky soils which were taken for comparison, repre- sents, no doubt, that of soil of rather more than average Jerlil- ity. According to Mr. P. De Gasparin (a well known French authority): 0.20 per cent. of phosphoric acid in a soil makes it .... very rirh. 0.10 per cent. and upwards makes it...... .. .. . rich. 0.05 per cent. makes it. . ..... .. . poor. Between 0.1 and 0.05 per cent. makes it . .. . medium. Schlcessing's average of phosphoric acid in soils is 0.17 per cent. The richest volcanic soils contain o.6o per cent., and the poorest soils quoted by Gasparin had only o.og or less per cent. The proportions of potash, in relation to fertility, vary in nearly the same manner. Mr. P. De Gasparin, in his " Traite OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. 13 des Terres Arabhes," gives the proportion of 0.14 per cent. of potash as a normal average quantity, and quotes, in the case of the volcanic soil of the vineyard of Lacryma-Christi, on the flanks of Vesuvius, the enormous percentage of 3.47 of pot- ash in the fine earth. This, however, is to be discounted by 34. per cent. for pebbles present in this soil. Our richest Blue Grass soil or subsoil sometimes contains more than 0.70 per cent. in the virgin soil, and upwards of I.oo per cent. in the subsoil or under-clay, and has no pebbles. The poorest Ken- tucky soil analyzed contains only 0.021 per cent. of potash. By reference to the appended tables of the relative compo- sition of the richest and poorest soils of Kentucky, and the examples of foreign soils which "are very fertile," the signifi- cance of the other tables of the composition of the soils on the several geological formations of Kentucky may be readily appreciated: It, palladxa iallu , j i k t -nlosut pue pues i t j-; 1 -X !aaiy lq _ -o t7 as'aultdill'u-1 pul. u(jr PUT, rull'univ I i II i 1 ,i i11 i I i i i ii I i I I cO c O C O cO i 10 0: _ t_ .tI' - t L-, _. 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COMPARATIVE VIEWS OF THE COMPOSITION puss Jo 'a-qqad g 1,9A1t , ' quouuswj [- I e PallaXa laJUeA4, -salex0 ! alq -n osuf[ PITT pur...' -u t I (eqo 7d) O ,Pti1otUldsoqU -;' aleuoqzua amiq ;; s-aplxo ; up.3sueusm puw ucur puN3 vui WnjV gsjllwtu apj - -NJOA pue a!U2jO I Er o 0o c 0 x 0Z I- C,, Q ;- = ,i C cc - . I r- o V: a- I -r 1aCe: 1 , cc e - -: o I- 1- -, I_ Oi O ; Or 011 .f . c In -r I- C I - M- cc: C,1I 1- . e I-! ' :' tc I- t- c cO11- t- C1. 11 .! . . 7 hO -I'11ho 5ci . . ri _O _ ,C c 1' cc CC 0.1 1- -tl Ct hO-k- 7.: C.:-tl = 0 0 C '-1 1 . ' cO CnO t X J9 ,r M - ,O , Eo -r_ C. L0 0 i = 0 0 Ph. CI1 .l Q i - - - - I . I . Z; ( . . Z _: --- - 7 -- - -- 7 :: I - I f- I- I rl :4 . i - I : I : .t- X I C C C1 ,, Cr. I I- 0= C.:, :cI hf Ci1 cc c' I- C: 0 . CJ . Y X -r U; CZ,, -o .0 S..ss IC'. C, c1 ,-r ._ 0 .2 ._ E 14 CZ, 0 0 5- Cs. ( i; 1; lz lz .4 Z; --' --' .Z z lz ,saM!ps alqnlow -ui aqj.ut qsoloj I i i I 1, I 1,I i I oo Q 00 o= Ct LI _ 'o M saeqlvssn -I- ex I t-_e sz ,.n C e il IC -nls- 00U pU = QC 00 QC 0 Cc cc n xie e 1 pajawxaoo O--------- ... . 1(w\ 07 T CD G- 1VO I-C e] = J. - - Cl t- I p1 B vatotl8Owaj.. . .. . . .. . . .. 9 L-, . e e ut o..o.. .. O0 l- 05 C'!CCt -V( 8lUaquluoMI .'rN e _ tt e CO- 4 , 4 - . . _ I OF THE SOILS, LIMLsTrONES, CLAYS, NIARtLS, &C. I9 D 01-1.158 = C 4; !`_ 6 6 q; : d I d _-; ; --; C o oc (M .- V: c C9 GX no F- v P:4 E- .,: X t-o 00 8. k vv .3... .. . . .. . _ _ _. _- 5 = = r IM -4Ie oo= ,, 6 \l 6 6 L.. .1..R. .. . . . en -t el - - _. C c c. c. 'J ,I 71 ju 1)411-NdXa J'ajvk _ na.s _5. w. v!i ggi30S3;d. dV M: e1 C,'1 i 1am O --0 z Po W =' - C-1 -_ 'sLqa'[Lae9 .saalulls ajqnjow -UT aqj ui qsuoa i COMPARATIVE VIEWS OF THE COMPOSITION pugs ao Islqa '1as 0 sa"exlls olqnlos e -ut ai1 UT qsu;OJ 'a 064 1 'tal 1t istalq .k. W aall PaId l ' 'W atS c .flosu! pue puug 4 c: i r ct-I- .P! ' XlJ q s _ t pa4JIUXxa 'rJseoJ . cnCi1 C P!PUau Aqdq pl t ateooqdooqd o o& C KvsaulB[ v jv . 0 ,a)euoylea aUlT! G-j uBjLfpulU ) 8-:in - ,ija lp U U ai! -el0A pUll 3TU114 4: . C . I . a i . C" v I -a ,. , - AL . ic - .-t0 - V z ri 0 z ' QI 0z I- I, i 1 s 0 . 0 z, ! l 20 I OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. .pUas Jo 'salqqad '0aWuJS Issuattumj; 31aog -Ut gill UT qsulo4 c 'au oz 2 Jr pala-xa a _ _ I _ I valaq!s alq ce, -I110811t pUB putsv t- C- CIO oc CO C4 W P!X() + - O sati3uIO O C :'alcuoKltna aturltI- O asatlt'uL'TlU pUlt I tt0a! ptlu uUItUtIlv -s-all"Il all)I -tLO'kPt; 3tltuR att' C . E . 0. . Ei . q 6, . 6 I. Z QO = . 1= 19 'I -1 _: w ;_h o E. ='VC p 0m ;v.:o C C z 0 -4 Q - r.0 Ml X; F.4 - z, _ pq - .4 1- E- _z ,_0 1- Ex ,, I 2 1 REVIEW OF THE AVERAGES OF COMPOSITION OF THE KENTUCKY SOILS ON THE SEV- ERAL GEOLOGICAL FORMATIONS i. Alluvial Soils.-Made up of the finer and richer materi- als of the uplands; present, generally, more than the average proportions of essential elements and conditions, except that in the Ohio Valley soils organic matters are somewhat below average in some. The Mississippi Valley soils contain more organic matters, clay, carbonate of lime, phosphoric acid, and magnesia than the Ohio river soils. These latter have more potash. 2. Quaternary Soils.-Have less than average organic mat- ters and of phosphoric acid; enough alumina and iron oxide, lime and magnesia, and average potash. 3. The Coal Measures Soils.-Present, generally, an aver- age composition, to be discounted by variable quantities of fragments of rock or gravel. 4. The Coni omera/e Soils.-Contain less than the average of all the essential elements; more than the average of sand and insoluble silicates, and are to be discounted by variable proportions of pebbles, gravel. &c. Yet no soil is so poor that it may not be made productive by the judicious ulse of fertilizers, if it has sufficient drainage. 5. The Upper Sub carboniferous Soils.-Contain less than the average of organic matters, but in other respects pre- sent nearly an average composition. 6. The Lower Sub-carbonifer-ous Soils.-Contain nearly aver- age proportions, except that their carbonate of line and pot- ash are somewhat below, and their sand and insoluble silicates exceed slightly. Gravel in variable, generally small, propor- tions, is sometimes present. 7. Waverly Soi/s.-Contain less than average alumina and iron oxide, phosphoric acid and carbonate of lime, magnesia and potash, and more than average sand and insoluble sili- cates. OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. 8. Black Slate Soils.-Contain more than average propor- tions of organic matters, alumina and iron oxide, lime, mag- nesia, and phosphoric acid, and less than average potash, and sand and insoluble silicates, but sometimes need drain- age. 9. Corniferous Limestone Soils.-Have more than average organic matters, alumina and iron oxide, lime, magnesi.i. phosphoric acid, and pqtash, and iess than average sand and silicates. 10. Clysper Siluerian Soi/s.-Contain more than average pro- portions of nearly all the essential ingredients, and less than average potash, and sand and silicates. I I. Siliciozes Mudstone (Middle Hudson) Soils.-Contain aver- age organic matters, alumina and iron oxide and phosphoric acid; more than average magnesia, and sand and insoluble silicates, and less than the average of carbonate of lime and potash. 12. Blue Linmes/one (Trenton) Soils. -Contain much more than average proportions of all the essential elements; less than average sand and insoluble silicates. The richest of all the soils. 1 3. I3ird-dsee iLimestone Soils.-Average organic matters, alulimina and iron oxide; more than the average lime, mag- unesia, phosphoric acid, and sand and insoluble silicates, and less than average potash. 1By reference to Tables C, D, and E, the comparison may easily be made of the relative composition of known rich and poor soils. By Table E we may compare our Kentucky soils with cele- b)rated European soils, as reported by one of the most expe- rienced agricultural chemists. Fable F gives one of the many examples which might be quoted of the changes of chemical composition of the soil wvhich results from long cultivation without manures. lThat the reader may appreciate the significance of the per- centage given in these tables, the writer will state that, by actual measurement and weighing of some of the rich soil of the Blue Grass Region, he found a cubic foot, in its ordinary 23 COMPARATIVE VIEWS OF THE COMPOSITION condition, to weigh 71.543 pounds. Calculated to the depth of one foot, the soil on an acre would weigh 3,1 I6,413 pounds. Other soils, especially poor, sandy soils, weigh much more than this. When we calculate into this quantity of soil the 0.404 per cent. of potash, which appears as the average quantity in 32 .Blue Grass soils, we find that it amounts to more than twelve thousand five hundred and ninety (I2,590) pounds to the acre. On the other hand, taking the small proportion contained in the Old Field soil (Table F), only .062 per cent., the quantity ini'the acre to the depth of one foot is only one thousand nine hundred and thirty-two (1,932) pounds. NOTE.-'In the early period of the Geological Survey of Kentucky, the late Dr. D. D. Owen gave special attention to the study of the changes in composition, produced in the soil by cultivation without manures, and consequently collected, for comparative chemical analysis, many samples of Virgin Soil with that of an immediately neighboring field which had been long in cultivation. Of the one hundred and seventy-three soil analyses made by the writer up to I 86o (see Vol. IV 0. S. Repts. Ky. Geol. Sura., p. 42), this comparison was made in seventy-nine cases; and in seventy-one cases the soil of the old field, as compared with the 'virgin soil, had lost notable quanti- ties of its essential elements of plant food. 24 OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. , a-wuoqiea uoii I ooooo 0 0 O ZC X i t( - =+v SN 0l -11!9 pUu 13lS o n+ . -_ ci Bps o. t o. cl Cv Cs s: CA lbod . . =. C p IC v 1 in'qalnSt Il- OL's CO (9co 7,-a)I OO p p i B iJOqtdsOqt j sap!xo uoiq puv mLmtunlN- i -tiojIu;) ls-aulfItq I iuoq.IH.)i" 'j A! IA J ! J !34rJ Sd '-I tll Iyoll CO -_= r_ I-ct v [--0: C 16t ; 0 tD C &n j4 IN_ _5 0Z1 0 '- cc cc c 4Z O t- C;:;r c.3;C; I _ 2.- 4 CZ 0 I ozz I Kz I I C.In CJ2 z-, . c0 a) -a C -& U3 oV OL W o C 2 Z o 0t o II c, 2.. I iK.__C I _ C0 z CL z &I z 0 0 o 25 COMPARATIVE VIEWS OF THE COMPOSITION -ajvuoqxao ucij Sa3T9a ,TM9puB 931THS C) c, i_ 1 _x;-, . ..7.. = co c] C,, _- =-- I 11 . .1I : I O o o 1= C) Ci t- cc - I _C _. 0 I0 00 CD ac ci lE c k eUpos )Qt Z C O03)C, C ,cI Il I . _ ________ pov s apqdn c ;+ , e , 1010 A. (-i -O 1A--I.ze _ .l tlieo V_,_ 7 1__' -: cc 5 0___ l __ ___ 'No gd) Ci 0-C! : I I -0CD 0 0T.10 t IdS Ct_C Dpx g IS1''- e _ -I 0aum OTIOtpu OqJ . ___-_______ _I__ ! T I al0cl i CID UOflpU UIvrnfluiq Ci Ci _1l _. _ _ _ C . 4 .L I' C.-o: -Uqll0 L!U: a,: 1!: - I : :: rs- a o a3 OMT- 1: _tj ,4 C- r, r- 50 Z I C I il 900 0 0 C'l oi .:i r 1ioo' I/m CI t- C'110aCXCiC.cc i , tr X)_- z v0_ 1. C l CC 10 L- 1. __ _l C l ' ,1 _______ . 4_-_ _ ___. . _ - IClNCnI . C CC X--'4 '5.'..l - - i z 1 - 00 2Q4- - c o C -w. X 0 C - _C p;: : :: Ct CC I -- s i_ B ,:- A . c 4. St- 4 - G-! - t,.O 4 C;1-r; - t . C 0 26 5' r. 0 0 0_ Q Ez 0 -2 m 0 Pk 0 I_ C C ;4 z C C z U: C Z -I . E-4 C . -r--I==o,-)[ _- c.. OvsOt-11 e:Oc Cc Cc _ cl I C,cl l QO I -' L 1I-Ic =1 o , -1 r- c: Qr oi , I ! - I= cC c; 1 27 .-4 . m .-I; 4 ._ - - C , . C C;s C) - nD IIVr- co I 0 0 .t. ........ ... VT t X;..,i . 4 -efl I I ;-Z I c- ji i. i, OF THE SOILS, LIMESTrONES, CLAYS, MARLS, &C. 0'a - C C cc -- zz- o lo o t saBa8 b = tJ l J L ' ,z, : c I, I C4 _ I IS 1 p t mB tnqdtlng ! .1 plau ouo r5- q l ; 0_ _ _ uolvpussululnlv Cr CCI --_ IO f1 -uoqjlua uiqauul v ce -Z I O C) O z t- tI ! ! Xj-j ag - 1 _a, o, _ I 1 28 COMPARATIYE VIEWVS OF THE COMIPOSITION . m, 111 ,-1 aquzwauaoUil c -1 0 ou ._4 p 1. -. ; Ews aI ,4 ! El ,.J C-C. _ Q es1 C ._ C._ ;: 7- -4 c01 1 _ _ l _-x'tr Ix -r t- X I - . .. I. . I.I.... . on 1 z 1 ooor,-:_1 1 -, t o .R-4o l ! + -r. F, 1 CC'00-t '-1-- _ --Xj3, __e 1f ''I 11 Ci'I11 --.,. I,. I-1ct-j- Gc C't1--C' 1 . . -i .- t_ 29 .. . . . . ... ... . . 3 i ci s r- , c ._ t- ft ; I . = .A A C I 22; X x, A-i e ZA; Ce _i C O : C s i .f C ro o & __i gui 3 8 oB sti w i 8 ' i,;11 1z, : . . . Ci V _h tA , _ I w -I _: s _ F A i i - t r _ _ t t i 1 _ _ I - _ + _ ,_ _ ; _f Z. X, _ i, _ - ! fflj t. _--t--n _ _ . . . _ : 5 7 _ __ ......... _ e _ _i or _ e _ _ -X,- t s r I - - . _ . i-,: it t- -I 4- I- ,Z t C Q. . '! I Z I -a -7 ';L 6x' 'r- ;i . ,1 I i Ir I I. t: i- I Si I !, t1 OF THE SOILS, LIMIESTONES, CLAYS, MIARLS, &C. tqea a v i 3iz, , , 2 RR t . _o . ._ m ooI , F I_ ,I I R F polal PU73 vul 11 ci .t , .lg- aaueustu0pU CgXto =s_t uo u uunYI'ai . 4t ,-: iI I 11 IiI i -11 I I' i I II! I I i i i I COMPARATIVE VIEWS OF THE COMPOSITION 30 .5 I o,: p11 0 :4 E- , 04 , , w 0 m ;D , 8i Ez 4vuoqj8g u I i i I t_ I- C ji C; Xt11 _S h C._ , 0: 1.11 = O- _r I :,e: C;. I- . SZ = 0_ O -noyuea vlauszuBls R== I" lll C. _ Z .m - I- r- f- t- _ X= -. : _t - _.- I- C 0 l_ .-I:11I Jl.I . olouoyvae atur1 ,... . . .]g. -, I= t 5, I Ca VC, . , . = - , .jc)!AUJ og!pads" . . . . .. ,_- -0 54C.,Z Cc j oj- . ,e ,c,0 X ., s ,e 5 _ _ ,_ 3t s 0 C: ._I c) r_ .. 03 tC ii ..:... I I ,3 OF THE SOILS, 1ANIESTONES, CLAYS, MIARLS, &C. o, Io i oooI c cec' tZ o z- -t _ '3 -I K1 _ o o I5 :1I coI= ot : o I _, t , I- :: _ I , l _ I. 00 zj w _C 2 --z jC N4 N CJ S w a- C) I._ w tL c T-I I -_ 7;. , , _ _ ,_ N 'A rci 0 C, 0 t) - C) wPS ' ! -T_ _t,- _ a pp oi udjn (90ga) 00. : f cl iIt eOt t plan :;)poqdsol.1I_ , _ - 'fpn o CC o Vo -c=_:-t . ,, o C, - Wp!Xt- eo l e m 3 LI _ Ix : _ , 3t t- _ un pe Dultuntv-Itc :v-O :C T i1 t. C1t- : 1 e_ I e, a] Cl ,_ - 1 COMPARATIVE VIEWS OF THE COMIPOSITION 32 t- = = R =:, 2 I- L"I c, . 0 . . = -r = -I. = :l 1-4 E-4 E4 .r ,I P; 0f P o Z)t 0" =' 1- M4s 0 F0 O n5 x I:. . l RO M: .1 X m O .4 ; c= i -!9PB all je= z ss ; 5. 00 e - g _ 8 0-4 oz --P c ,___ :; -_= 0 = = c; 2 _ _ - g Si = jC t eq OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. .W 0o0 t ;C Ct:R,-4 r- . . '; o _4 . d!1 ob ct - 04 C001U . . . . ll C! C',u Cm 1. 1) t- C'i-:- to so 0 . . t. .- 4 Q; C C 0 0 0e E r =1 o; o o0 -L' V :E X ; k 21 3 i z 0 rx4 0 E4 2 8 Q Pk 0 0 = 0 ;- 0 S. "I I :t S V. 0) S. i GFi.oG. SuRv.-3. ! ci 1:!- G = M ' __ 00 -0 LO It .r l a,...-r CCa Go U E- SZ F0 ._ . .R I- u0Q f C0(w 33 A 0 C 0 42 2 U m i U) I a 0. a I .2 i I, S 3 I e 0 E . A- C, SX 1. 34 COMPARATIVE VIEWS OF THE COMPOSITION 8a00 = cl .c 0t ceNF_ Oi: t Cb t_ 14 E + e: XMC' nC'4 , 1s i tt : !Csii .R ,s . I z Nas Ff fl i, xs be E3 -EEE -,bo E X \ 33s,33t, 3943 t 1543 t33c Ad lEa ,.i X OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. 0 LI: OO 0 b. 11 0 C3 8 X g3 e ecd2 E E h -s E ,0 .E ''l nEE EE00 9- C -4 9- W0 Z 3 P 2 2 b.- . . a fi _.,3 B a Xs ' C ZS: a t- -= 8= 4 V :R 1. 4- 35 L-. a4 a r.. t S W. E- i W 9 c ._ -3 z C): 04 I- 0-4 &-4 54 0 1.'; le PJ 0 CEd ;4 w E- 12 - -r00 N v t- CZ -11.1 A . 11 C C . I 36 COMPARATIVE VIEWS OF THE CONI POSITION :eOl 3i-O: c ekl _ k __ _-O 2 .. , _ . qj - = = . E ',,, S 2 . Gi n . - _ _ _ t. r C U - . _ . _ t. w . UC Q V. C _ _ z - _ _ . _ _, I1 .5 I 3i .i Z -1 0- : P; Z E-4 ,4 Ga m ; Z,. 1:1 1 2 - =.. -m i 8o tat et I I S At ' X . j; zl = 3 [ ;; S ;, X _ e ,;. :o N , ; e , N 1 83 _ f z t ; P; ;: G 4 ; 8- at _ . . O - O 5 e oC . - . , 4 O E e 2 fl 2 ; fl = n fl C .C5'1l, Z ; ti ;) C;W 4. a) , t-- 3 30 pX m 2 . w .Y S a C a6.D OX=U' t4 m Ctoe ot--0 = (1 tc -, -1 cl I-, li_ _ I tI . t , ; .S I q !I ! 1 : 0 OF THE SOILS, LIMESTONES, CLAY'9, MARLSj &C. to to pE ,_ .._. . ; o1 ;t' 4 _ b.b rru, ffi cd Q) 0:cc e 1 t Ca r en Cto C; _c 0,; t W _ ___ __ _ _ -C _ Q g -St3 o GENERAL REMARKS ON THE LIMESTONES OF KENTUCKY. As may be seen in the appended tables of average chem- ical composition, these limestones present a great variety, and are applicable to numerous practical uses. For building stonies, the limestones of most of the forma- tions may be employed, those especially which can be quarried of suitable size and form. The best and most durable are those which possess a close, compact or fine granular-struct- ure, without cracks or crevices, which consequently would not absorb much water, or be liable to be disintegrated by frost, and which do not contain much iron pyrites or iron protoxide, and are trot full of fossils or chert. The most durable of all the limestones hitherto tried are the compact homogeneous layers of the pure magnesian limestone of the Lower Siluriari group, of fine granular structure, such as was used in the Clay monument in the cemetery at Lexington. Some of the beds of the Birdseye Limestone are compact enough to receive a good polish, and to take the name of marble. The Lower and Upper Silurian groups, including Lower and Upper Hud- son, the Corniferous and Upper Sub-carboniferous groups, as well as some beds of Coal-measures limestones, &c., all il- clude layers sufficiently pure and homogeneous and of proper structure to answer well for building purposes. The olitic layetrs of the Upper Sub-carboniferous forma- tion are remarkably pure carbonate of lime, containing more than 98 per cent. of that material.. It would, by calcination, yield a very pure, white lime, which might be utilized in maniy manufacturing processes.. Pulverized, it would prove availa- ble in the manufacture of glucose, for neutralizing the sulphuric acid employed, especially as it contains but little magnesia. Some of the layers take a good polish. The Birdseye lime- stone is also quite pure, and would yield a very white lime. Some of its layers are susceptible of a good polish, and have been used and known as - Kentncky marble." It is quite compact, but somewhat brittle. OF THE SOILS, LIMESTONES, CLAYS, MAILS,. &C. Some of the layers of this Sub-carboniferous limestone are available for lithographic purposes. These have been. found and quarried ill Menifee, Barren, Hardin, Estill, and Meade counties. Their availability for this purpose depends mainly onl their fine granular structure, their freedom from fossils, flaws, cracks, or irregularities of texture, and the pos- sibility of obtaining slabs of good size of a homogenCoL: character. Those which have beeni analyzed contained a considerable percentage of magnesia carbonate. All of these limestones could be utilized in the preparation of mortars and cements. Of course those which are the purest would slack the hottest, and give what is technically called -fat lime," and would probably harden in the air more firml), when mixed with a proper proportion of clean, sharp silicious sanid, thani the less pure lime, and hence would be preferred by the bricklayer and plasterer, and for preparing the whitest wash; but any of the ordinary limestones of the several geo- logical formations may be used for building purposes, and experience has shown that some of them which contain con- siderable proportions of silica and silicates, alumina, iron oxide, and magnesia, although their lime may not slack so readily or so hlot as that of the purer limestones, yet will resist the action of water and of other atmospheric agencies better than some of those wvhich are purer carbonate of lime. For ce/nc/its, or mortars which are used to withstand the action of water, so-called raulic or water cements, what we ma) call inmputre linmcstones are generally available. The hy- lraullic or water limestones frequently contain a considerable pro ortioln of magnesia. Indeed, some quick-setting water limes seem to owe their peculiar property to the admixture of magnesia; but the cement of such limestones is said not to be so durable or so perfectly water-proof as that con- tailing considerable proportions of silica and of alumina and iron oxide. "A very striking proof of the influence of mag- nesia is afforded by the limestone from Tarnowitz, which hardens extremely well, although it only con- tains 3.35 per cent. of silica. This limestone contains 29.32 39 COMPARATIVE IVWWS OF TH4E COMPOSITION per cent. of carbonate of magnesia." It contains 16.83 per cent. of carbonate of iron, 3.75 of alumina, and 49.o6 per cent. of carbonate of lime. (Knaapp's Chlem. Technolog ', vol. 1, PP. 378, 385.) Proportions of potash and soda not given. By reference to our tables of average compositions this will be seen to resemble some of our Kentucky limestones. The statement of the composition of the celebrated hyclrau- lic limestone from the neighborhood of the Falls of the Ohlio river at Louisville, Jefferson county (see vol. 2, 0. S., Ki'. Geo/. Reep/s., P. 220), may be given as the type of that of a good hydraulic limestone, dried at 2120 F., as follows: Per cent. Carbonate of lime . . . . ... . .. .. 50 43 = 28.29 per cent. of lime. Carbonate of magnesia . .18 67 = 8.89 per cent. of magnesia. Alumina and iron and manganese oxides . 2.93 Phosphoric acid (P2 05).. 06 Sulphuric acid (.5303)..... .. .. .. 1.58 Potash. .. . .. . .32 Soda. .. .. .. .. . .. .. .. .. .13 Sand and insoluble silicates .. . . . . .25.78 Containing silica = 22.i8 per cent. oss. .. .. .. .. .. .. .. . .. .10 100.00 The reader is referred to vol. IV, N. S., of Ky. Geol. Repts., pp. 404 to 408, for more full statements and remarks in rela- tion to hydraulic limestones and cements. According to the experiments and analyses of Berthier and Kersten, 5 to 9 per cent. of silica, alumina, and iron carbonate, with from 0.40 to 5 per cent. of magnesia carbonate in the composition of a lime- stone, give to it a very moderate hydraulic character, while I3 per cent. of these ingredients, with 4 per cent. of magnesia carbonate, give it marked hydraulic properties. (Aztapp's Chem. Tech., v. 2, j). 379). But, as stated in vol. IV, N. S., of Ky. Geol. Repts., above referred to, the presence of the alkalies, potash, and soda no doubt is an important factor in the composition of a hydraulic limestone. Limestone, calcined and air-slacked, or simply ground up without calcination, is employed in some localities to improve the quality of the soil, and increase its fertility. It may oper- ate in a variety of modes. Its constant action is to neutralize 40 OF THEF SOILS, 11MESTONMS, CLAYS1 MARLS, &C. acids, and to decompose stulphate of iron and some forms of organic matters, aiding in the formation of amnnmonia, and favoring nitrification under some circumstances, thus assisting ihr supplying available nitrogen to crops. Applied in large quantities, as slacked lime, it greatly improves the texture of heavy, tenacious clay soils, rendering themn more friable Dand(] penetrable by fluids. No doubt, while in the caustic state, slacked lime acts somewhat on the iiisolible silicates of the soil, and sets free some of the alkalies and other valuiable ingredients. But it is highly probable that the most profitable lime for use as a fertilizer would be that wvlich had in its com- position the largest proportions of potash. phosphoric cid, sulphuric acid, soda, &e These valuable elements of piaiit food are in largest proportions in the impure limestones, and would be more quickly available in the calcined lime than in the ground limestone. It appears to have become somewvhat fashionable to apply ground limestone to the soil as a fertil- izer, but unless a limestone very rich in phosphoric acid and potash is selected for this use, it is very questionable whether it would be profitable on any but a soil which wras very dcfi- cient of lime. The practice of adding ground limestone to commercial fertilizers would generally be profitable to the manufacturer only. One very important use of limestone is as a flux in the smelting of iron ore. For this purpose a carbonate of litme containing little or no phosphoric acid or sulphuric acid or pyrites (iron sulphide) would be most appropriate. The presence of moderate quantities of silica and silicates, or of magnesia. potash. or soda, would not be objectionable. In- deed, the ferrUgilloUs li Mestole s founl1d in the coal-mlleasures would increase the product of iron; and the oxide of mangan- ese, which occurs sometimes in these limestones in notable-: proportions, would improve the quality of the fluxing material, as well as that of the iron produced. 41 .qqclod - l-5 C- ' Cb! c I cc: ,; oc 42 o 8 : _ _Q D s 6 C V _. _. f, - ., ;, pr E- E-4 t-,-: -, = 18 -e I- _,= o -It e: :,; '_ :f- _ c - o ... . . . -r _ . 1, , ,: A 11 _ _ _ _ ,:A! t cc -Z t- ppuaisld -oll s _ ' ' C . I- - or, t ' , l B!SaU2EV: C't C)C.:)- p!Xo-lad I c. o cl -O c ___ _T O-f r C ;G ICA ,_ ,bf A .. , _ i so i 'l 11 s I. e c:' ; I._ li 11 t-- 1 ,', ;j cc ll C-o I l '; zAs ,, .. I . I 11 t_ eI t _j ,Z, 1' --4 I - 'I s . . _- ;1 , C[ -x i C O ' O j t- _;: i 1 5 0 t-t- t- ! t ; I C: ;' QC cui 's s 11 1 . 4: - ol ll : :zZ onC:Wll- ,j' i l t E - t - - :S l - c ol c l- x - ; c Wt tg , 117,_= I i- - ;t C ' i .C t; - ,: _- a : X . j il W . X COMPARATIVE VIEWS OF THE COMPOSITION Issol pug laajvj fc c -t ce - o 0 VD It t-t C:) cl O- co - C l 1: I-, C:: ! CD 1 C1 C C1At C V. GO 1- 15 l It'.) 41 _ O m c lj !l I I iI i! 1: I ! .; c 0 -:,_E :I - 41.4DVD .d . Ii It- X co -r - c _ _ . - _.. Z. 7C, OF THE SOlLS, LIMESlONES, CLAYS, MARLS, &C. 43 __ C 111 4 , l- t_ A I qsloI , ,: !,_ _l 1; - cl Cl p e. It li _: _! _- 18a3OJfJUolil 'lC,, T1 r tAI -I ____C_ -cup ln eV cc C".)e cD c l I1 I I!, i II I I I I' t I i 44 . o .n o E" E- C: c-- E-4 X -- QC CD t-. . 00 = I Co_ I ':C- v C., C. - I ,- o) , = C-,a z . . I .-t-1 6 . . 1. r; :i -- C ii -V I _ C - C, . .2 1 .7 ' - .1 - r, gS C1 C.) C5 rrc cr Cil t- -, C,, I I i! i, I: 11 14I i X 'R3T1!S -T -t- 1 C . _ '7 z2 --- CONMPARATIVE V'IEW5S OIP THIE COMPOSITION 'png OUTJ 9RqoI lpuu J11m it sr_ I1 :cc -ppuc ajoqjdsoqI OF TIHE SOILS, LIMESTONES, CLAYS, MARLS, &C. Oo 0 1- 0 o i'- . 0 -0 C; - oi 0 0 .. C- 0o Ci C : - 0 0 -1' - ' 4- .0 0 0 C) . 0-' -. C) C) -4 0 Ci2 4.- 0 =j 0 4.- 0 K V. -4 4...-. s 45 06 i Ci L: L:4 0. 4- 0 _0 0-L. v5 V C4 cia C) 0 E C 000 i 0 4.2 0 ;4- cj:l I 0 C) I t12 0 _. S C) ,0 4-. ._z .2 COMPARATIVE VTEWS OF THE COMPOSITION i .5 F-: S.. El 11 C Z 7i _,ct ! Q ! i ,_ i ! , ] . , s: i , - I "C I ! _ , , _ I 55 I I J _ _ , _ s0 v- ) I .. I ! I . . . . I . s , fffii i : C . b. . _ - ! _ - ! ; J ;'; i __. j _ O t .. : 2 C': 1 .. I . . . . . . . . .. I I :o, fl I Cv - I . Y . X I _, , , t t _ _ _ C) . 3 _ = _._ Q ,C sQQ I =u I;- I 11 t.- i ' i _ I _- _ Cl Y i c; ., E ', s r, 9 0 I Y _ f V _ C1 : ! I. - i ! a I :h ! xi o , 2, Y. I K _ - K 5 ! I Q l sr3 I_ cr. , I ;''_. _ ;) ! kU . j .fl; 5.. i E i. . I If. . Mc.. Z 0 = E C oI Ir i ._P. I In I It 46 .r 'i L T. - t _ .1 - ., r,- t . , I _ ; I 0 0 q 1 0 F- 0. Fy4 - C C C C Q hL- t a :12 C- 0 .5 0. E C; I 1 '.1 I I L- I I i I I I I i . I.11 1 I E I I= I I- 1 4 Cs . I - P S.. t., V:, :2 F-. C, I i- OF THlE SOILS, LIMESTONES, CLAYS, MARLS, &C. 47 - 0c I- I 1.,_11 I-5 I I l C 017 I Q'l C E 1 COMPARATIVE VIEWS OFIT lIE COMPOSITION .I . o .. -t =1- C" t15 C 42 C _ 4, IQc C) CO k i , _C O 01 C, , - CiJ 77, tz C;s Ci O : 5_ C2 ,Z m _g 48 -4 0 -4 0 I II GENERAL REMARKS ON THE KENTUCKY FIRE- CLAYS. It will be seen that the best and greatest quantities of our fire-clays hitherto observed are found in the Coal-measures and Tertiary formations. In the former they are usually in an indu- rated condition, requiring grinding or exposure to the atmos- pheric agencies to make them plastic. In the Tertiary beds they are more friable, and easily to be kneaded with water. This marked difference is greatly owing to difference in com- position. The Tertiary clays contain much more silica and less alumina than those of the Coal-measures, and much of this silica is in the form of fine sand, as may be seen by reference to the foregoing tables. This causes the Tertiary clays to be less plastic and adhesive than those of the Coal-measures, but probably may cause them to be rather more refractory in the fire. The plastic clays or Potter's clays have not been examined in so large number as the fire-clays, but have a wider range in the several geological formations. All forms of clays have numerous industrial applications, varying from the most costly products of the ceramic art to the rude brick or draining tile. INFLUENCE OF THE SEVERAL CHEMICAL INGREDIENTS OF CLAYS. Pure hydrated aluminum silicate, which is the essential basis of all clays, has a composition represented by 46.3 per cent. of silica, 39.8 per cent. of alumina, and 13.9 per cent. of water. = (A12 03,2 S.02, H20.) It is sometimes found in the min- eral kingdom in varying conditions of purity. The mineral halloysite is of this nature, and the so-called Indianaite of Cox, having a composition represented by 45.90 per cent. of silica, 40.30 per cent. of alumina, 13.26 per cent. of water, with GEOLOG. suav.-4. COMPARATIVE VIEWS OF THE COMPOSITION o.i98 per cent. of potash, 0.204 per cent. of soda, and traces of lime, is of this character. In the pure state the silicate of alumina is highly refractory, being infusible before the blow- pipe, and practically fire-proof. It shrinks so much on drying, and especially when calcined, and is hence so liable to crack in the fire, that it cannot be made practically useful as a fire- clay until mixed with a considerable proportion of pure fine sand or ground burnt fire-clay. The admixture of fine sand does not sensibly reduce its refractory characte r. provided it is pure and free from fluxing materials, such as iron or man- ganese oxides, lime or magnesia, or the alkalies potash and soda, each of which substances increases the fusibility of the clay in which they are present. According to the experiments of Richter, in I 868, "the refractory quality of clays are least impaired by magnesia, more by lime, yet more by iron oxide, and most by potash." It is probable that soda is at least as active in this respect as potash, and the oxide of manga- nese more so than the oxide of iron. The phosphates also increase the fusibility of the clay. The admixture of pure sand diminishes the plasticity and also the contractility of the clay on being dried or calcined, and increases its porosity. The same object is attained by mixing it with ground burnt fire-clay, plumbago, or ground coke or anthracite, and these substances are believed not to dimin- ish the refractory quality of the clay. The well known Hes- sian crucibles or sand crucibles are an example. The Hessian crucible clay is composed of 71 per cent. of silica, 25 per cent. of alumina, 4 per cent. of iron oxide,+ mixed with one third to one half its weight of quartz sand. It is said, however, that the quartz sand increases the fusibility of the clay when it is heated with fluxing materials, especially with oxide of lead, and that the substitution of ground burnt clay, of a pure kind, for the quartz sand, makes the crucible more refractory. See Ky. Geol. Repts., vol. IV, N. S., pp. 164-5. f This quantity of oxide of iron no doubt decreased the refractory quality of the an, but this influence is somewhat counteracted by the large proportion of silica in the clay, and by the sand. Tihe proportions of lime and of the alkalies are not given; soeue are undoubtedly present in this clay. 5o OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. The black lead crucible, so-called, made of clay mixed with plumbago, is less porous, and takes a smoother finish than the sand crucible, and is more durable and less liable to break; hence it is used in the fusion of the precious metals and steel. Fire-bricks, tiles for lining furnaces, &c., are also made of the most refractory clays, mixed with pure sand or ground burnt fire-clay. For making the large crucibles or pots used for melting glass, in which process the material is not only exposed for a great length of time to a very high temperature in the fur- nace, but also to the influence of fluxes in the contained melted glass, clay of a peculiar character, called glass-pot clay, is largely imported into this country from Germany at a considerable expense, it having been somewhat purified in that country. As may be seen in the foregoing tables, this clay, as com- pared with the general average composition of our fire-clays, contains more than the usual proportion of silica, viz:- 7I.686 per cent., including the fine sand, it being exceeded in this respect only by some of our Tertiary fire-clays, which contain 77.739 per cent. (In regard to this ingredient. silica or sand, something depends on its state of division or combination. In combination with the alumina it forms the tough, plastic basis of clay, but in the form of sand, the coarser it is the more it diminishes that toughness or plastic character. Sand, in a very fine powder, partakes of the plastic nature of clay on mixture with water.) This glass-pot clay contains only a medium proportion of alumina, viz.: 21,30 per cent., and a comparatively small proportion of iron oxide, but more of this injurious ingredient than some of our Coal-measures fire-clays, and not much less than some of the Tertiary. It has, by com- parison with our fire-clays, small quantities of lime, magnesia, and potash, resembling, in this respect, some of our Coal- measures and Tertiary clays; it also has only a very small proportion of soda. In England they use their Stourbridge fire-clays for the preparation of their glass-pots,' and the chemical composition 5 I 52 COMPARATIVE VIEWS OF THE COMPOSITION of these, as given by Knapp (C/temn. Tech., v. 2, fi. 35), from analyses by Richardson, is as follows. Silica (including fine sand) from .61.15 to 68.05 per cent. Alumina from... . . 18.18 to 25.0 "0 Oxide of iron from. ........... . 1.10 to 5.10 Lime from............. 0 to 1.30 Magnesia from........... . n. e. .85 Water from.. . . 6.00 to 12.50 " Alkalies, potash, and soda not given; probably as above -- 1.90 per cent. On examining the tables of the coniposition' of our fire- clays, several may be seen which would most probably serve admirably for the construction of glass-pots, n ore especially if the same care be taken to prepare and purify them as is used in Europe. In using clay for refractory pottery, fire-bricks, or tiles, &c., much depends on the preparation of the clay. It is laid up ill heaps or ridges, fully exposed to the weather, for months. The water and oxygen of the atmosphere, and the influence of frost, disintegrates it and measurably washes and purifies it. By the combined influence of moisture, oxygen, and any organic matter which may be present, insoluble iron sulphides are converted into soluble sulphate, and insoluble iron perox- ide changed to soluble iron bi-carbonate. Some of the lime and magnesia are also washed out by the rains as soluble bi- carbonates, and some of the residual potash and soda, which entered into the chemical constitution of the rocks from which the clays were originally derived by the process of prolonged weathering, will become separated by the same process, and washed out by water; and thus the clay becomes greatly im- proved in purity and in its refractory character. The washing part of the process is aided artificially, and thus also are the pebbles, fine or coarse sand, separated, more or less, as may be necessary, from the finer particles of the impalpable silicate of alumina. In the purification of some clays, the powdered and s6ftened mass is mixed wvith impure water, containing organic matters, and allowed to ferment or rot in a warm atmos- phere. The decomposing organic matters aid greatly in the separation of the- mineral impurities, by bringing them into a soluble form, as detailed above, and thus facilitate their re- moval from the clay by subsequent washing with purer water, OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. 53 For crucibles, glass-pots, fire-bricks, and tiles, very refrac- tory clays alone can be used, containing as large a proportion of silica in the form of sand, more or less fine, or of ground burnt clay, as can be used without destroying the plasticity and adhesiveness of the mass, and the smallest possible pro- portions of potash or soda, lime, oxide of iron, or magnesia. The mi.ost refractory clays burn wlit(e, because of their v; . small proportion of iron oxide, which, when exceeding one to two per cent., begins to give a yellowish tint to the burnt clay, increasing in intensity and passing into various shades of orangei red, and brown, as the quantity' increases, and proportionately increasing its fusibility. The best fire-clays should not contain more than from 0.2 to 0.5 per cent. of either lime, potash, soda, or magnesia; their fusibility in- creases as the proportions of these fluxing materials increase. For many of the ordinary uses of these clays, however, these proportions may be double, or treble in some cases, without detriment, where the heat to be resisted is not very intense. But for the numerous uses of the potter, in the manufacture of the various products of the ceramic art; from the pure and highly artistic, richly decorated porcelain, the parian, wedg- wood, stone-ware, delf, queen's-ware, majolica so called, down to the simple red flower-crock or the common brick, clays less refractory and less pure are available. Even many of the marls, or mearly clays, which would melt into a slag at a bright heat, or become deep colored, red or brownish-red by calcina- tion, because of their large proportions of fluxing materials, icluhding iron oxide, are employed; and it is a rem-arkable fact, demonstrated in the most ancient remains of human art, that whatever may have been the kind employed, articles made of clay, if they have been well burnt or calcined without fusion, withstand the influence of time and the atmospheric agencies better than any other building material known; while ancient granite, porphyry, and marbles, are found to be cor- roded more or less, the clay tablets of the most ancient peo- ples are measurably unchanged. The pure white porcelain or china-ware is only to be made COMPARATIVE VIEWS OF THE COMPOSITION of the primary clay called kaolin, derived from the decom- position of white felspar, mixed with a proper quantity of- pure powdered quartz and undecomposed felspar, with some- times a certain quantity of fluxing material, which causes it to soften somewhat or frit in the heat of the kiln. This soft- ening or fritting, caused by the presence in the clay of lime, the alkalies, or other fluxing materials, also gives the com- pactness and solidity to the so-called " stone-ware." But the hardest and most refractory Berlin porcelain used in the chemical laboratory has a composition represented by silica 72.96 per cent., alumina 24.78 per cent., lime only 0.104 per cent., magnesia and iron only traces, and alkalies 1.22 per cent. The clay used at the Royal Porcelain Manufactory at Sevres (Fr.), contains silica 58.0 per cent., alumina 34.5 per cent., ilime 4.5 per cent., potash 3.0 per cent., being thus more plas- tic and more fusible than that used at Berlin. These wares are of considerable variety, and the glazing or more fusible glass or enamel with which they are coated in a second burn- ing, penetrating the porous burnt clay, converts the whole into a homogeneous, compact, translucent material. Potter's clays, as compared with fire-clay or porcelain clay, are generally more plastic and adhesive than those, because of their larger proportion of alumina. They are found in every condition of purity, but contain notable proportions of the fluxing materials. Plastic clays or potter's clays may vary in composition greatly: the silica from 42 to 70 per cent., the alumina from 20 to 40 per cent., the iron oxide from i to I5 per cent. or more, the lime from 0.5 to 5 per cent., the alka- lies from o.5 to 2 or 3 per cent., producing wares more or less refractory, firm, porous, and colored, and applicable not only in the highly artistic pottery and terra-cotta, so useful and durable in architectural ornamentation, but in the drain pipes and tiles and the ordinary building bricks. For all these purposes, except for the manufacture of fine porcelain ware, the clays of Kentucky are applicable, requir- ing only the hand of the skilled workman, and the proper use of capital, to make them profitable. 54 OF THE SOILS, LIMESTONES, CT.AVS, MARLS, &C. 55 50I puU14WA CoOi Z- LNi0 - rIe i _ _e _! oo.-r z -CC I =1_ C4 _ _ - ient4 -t_lC '.,t p!p)1 arrotlds:oq4 , _ ! p [.3 twautldsotoC N;O L... i I'la3Il;_ ai_i01 C rr _o C)CI;- .1VD I I; C C,10C _ = Cr Co _xco cO COt c avultIz.csFv - Co'CLOri c - 0 -ap!xoaad Uoi 1 ClI O e e CoCo,-0: DO CIOC'j IN Co _ _ _ _ _ _ _ _ _t t cCO- - t C - o I :Ii 0 - 1 0i 0s c: o o et' CO ,.-'CIIi - tl_-Co _ t smrnltny0 o I - _ _ Ct__ IIA-__ji t V QC ' I C1 o C L' C o C _a_ - ;,i I- ;.o &_ La . !ft_4lw X r fg 6w'- : 00 0 s j1. 11 Co Z 0.1 .X zse - - jl , Iw_t f , II I Z Z o Co, N- i o -, - , _ Co c 0, 0 xtIc er t, X ,: 4 o v c.-C, -q"Jod 1w IR c:i I,,) C o -1.! '00 z) C ;tt n1.!G1 plae ouoqdsoqa da= .1 BiaU38i C. t )1 nt IR c 1- o: --C1C: k cc Cl -ap txcuadu ij 8 Ii1 1 t t t ' I 1 11 1 C:li l t- al 1 t-4. 4 l 0 - t,, t o lmnzIVt 1 _ Lt: I s c 11 D 1t Ctt co e I c: I i i I i j I i i I 56 L-4 5:4= C CE4 . co 00 00I oo = Io I t.B I li: ti I .g : i _ ! t- C1 : , 10 z I _, . X Cs S;, ri, - I : : : X F_ _ ; t: .: 11 .e . , X-C- C) i: A tC I C) L r4 Y -_ 5 a_ -t ip C, CD . _ -10 -2 -o '.2 1 C, C- rC . _ 5 BC 11 S) . 11 t5 X 11 _ 11 A,;t t- . 1I E0 :Zz . l! s; I t - 2 X; -r I X,7 . ! p f t1 : t l _ . - 14 G 11 3Xb 11 'D o S 11 - CC l 11 tY Z;, z I-- z . F- N _: C p --) , R = 0 - Z z I z 52 T . f cr2 c W -11;, C. -Z C. 0 6 U 0 4 t=,L) pl-z l' t: . l - l; c : ' r - e l - - r - - ' v o . i - z; . I ;4 i 1 F.N - ! =- 1 I' I- . ' 1, -aQ I' s 1: - O I . l;=i= I ax li x, S 11 m; I i I I i I COMPARATIVE VIEWS OF THE COMPOSITION '8S01 Pug -'Gq'BA OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. 57 "; -P S -o L: , CO tI- 0 - l 1w00 I" I; wO - CO t t 00 10 -4,-V CO 01 ' 9-4 1- ZC '7- 1e' 4; 00 CD O 0 0 0 CD0 O t- C C'1 3 t-. = 4; 01 ht&- UXl 3O t = . 00 ,- .j ,3 - _4.1 v10 I O ln I 01 . 05 kO 01 t 00 00 0P I-t U t- - C iO Oh &I _O CO I- _- Co i0 I" p CO b 0 -S . D _ _- 0 O C O O OM . ._ 0 -I ! . _ _ ;- r_ Mo -.z : . t r-00 Ut I= Ci 1 10 CO 1 _0 0 CO Ci _- iO_ z - C 0_ 1-X X li- s 50 T!O :g O 11 0 X e s - I l s c l I. .1. 01c I 00 CO.0 CO. I Cs C. j - z. -N 0 ; 0j 0 1 ! 05 Dz -i zU: I', X ,I 4_O- -'6Z ' , , l C.) CC -d 2CC , - B- - C zI h 3J 0 0 0 _. . _ c ec ts . !q , -q uC: C, C :: O .0 .1 zo - rC. i) -S 15 _i za 0 0s S0 :2 0 C' , I 0 C 0 0 0 0 o r- - x o, I 1-t U = 0 c _ _ I-- I _I _ t_ I- F- 0 C w -h -. .O . . .1 0 10 CO _c t -P 41= (1 _! 10 29 Cl C' .9j O ' Z - 0_ . C; 1 C. . B- 00- - -h.J. C es - 0e 0- - 8) : 0 P I CO a - I-hh I CO M 0 t"- 0 I C" cm ".0 COj 00 COi CO t- VD 1. I.- .z. Z .. 0 Q 01 10 Ci I Il I I I I J I i I I I COMPARATIVE VIEWS OF THE COMPOSITIOR -not PUs Jx&i .u8pos - 4 Cq lgo za) Ct - pt au uLoqdsoqa wtuusKdg . I -uy -apixojad uoQ Ico co 20 ,_ _ _ _ _. 5- Cl. z z Oc CO 04 4 c N4 58 z4 zo 0 cc - V EV o a C. 8.0 vi 0 0. o ci S I 1 1 1 1 I I i I tostl C1 liOlI-, 1:: _C K1 8pi] iCit_4; fil_ t2 1 3 IIt, 1.M . Sw I- .- I t1 ce secloo c 1a e f i !o p!e;aqsoqat-o c- .-ItC ='N ; Ic I _)C ; t t_ N CCO t- . 0t 4 Pos alloqdsoqa C C l 0 0- ' _ e t- 3 C,-b elsauauX ul M co 1O- c o.. _ l II Cp t-,] C6 t o: vi L' t.Z _ C ' = M ut w =i CCiC o ttOi te ap I- C) M ] t_. C, C., C s 'Btl[[ltil C= _z - o 1 1 U: C.M = ,o i to OF THE SOILS, LIMESTONES, CLAVS, MARLS, &C- 59 CC Cl E- Z; d G _ , 00 M -!. 4; C eq o, i= e r-i oIw t-3 F C" 8 = = ' t-oc I.. . ..l 0. LIT Cq 11 00 11:v t- 00 az 0 C .C- .t! .0 1; 1 9 I 9 .so .0 N 21 r. -.4 -4 Q 1 I00 -Z .J.l R 'i 'a 2 9 .2 .0 t aI 9 in .I.- -ssol Pul3 Ja)13AA S _d . , a fl . e et . taa ,QO-e e 's4C v WI CC-: Z ; = a Wn ng w ,4 0O .;o; P OOv e E-O & O E ; 0 0C: C _c C 7:e0o . - s c 4 c: ce c.P.2 OR O '- ;g el s C, P. vOVUoO d COMPARATIVE VIEWS OF THlE COMPOSITION The number of these marls and marly clays, &c., which have been brought into comparison, viz: thirty from eleven differ- ent groups, is too small to show the influence of the several geological formations on their composition. So far as these go, they show the Tertiary, Coal-measures, and Middle Hud- son marls to be the most silicious; the Upper Hudson, Upper Silurian, Clinton, Coal-measures, Tertiary, Birdseye, and Lower Hudson marls contain the most lime; those from the Upper Silurian, Middle Hudson, and Upper Sub-carbon iferous groups contain the most phosphoric acid; those from the Trenton, Lower Sub-carboniferous, Upper Hudson, Birdseye, Clinton, and Lower Hudson groups are richest in combined potash; and soda is in largest proportions in the marls from the Coal- measures, Birdseye, Tertiary, and Lower Hudson groups. Marls are impure clays of variable composition, generally containing a considerable proportion of carbonate of lime. They pass, on the one hand, into clays proper; on the other, into limestones; while they may shade into iron ores as their variable proportions of iron oxide increase. They are usually, even when in the hardened state of shale, readily disinte- grated by exposure to the atmospheric agencies. The (arli- est use made of them was on the soil to increase its iFertility, which it was supposed to do mainly by supplying limie where it was deficient, or by altering the consistence of the soil when too compact and heavy, or too sandy and light. For such uses the question of the cost of transporting and apply- ing the large quantity required to alter the physical char- acter of a soil is a serious one, and hence the modern use of marls is mainly restricted to those which contain much lime, or which are found to have much potash or phosphoric acid in their composition. It is found, however, that the potash and phosphoric acid, although contained in some of these marls in notable propor- tions, are not readily or quickly available as elements of plant nourishment; the former being probably in firm combination with the silicate of alumina, and the latter forming insoluble phosphates of iron and alumina. So that, like a subsoil or 60 OF THE SOILS, LIMESTONES, CLAYS, MARLS, &C. under-clay, in which chemical analysis demonstrates the pres- ence of considerable proportions of these essential materials, they prove at first less suitable to vegetable growth than the more porous surface-soil, which contains less potash or phos- phoric acid, but which is darker colored by the humus which it contains. In the course of time, by the action of the atmospheric elements and of the humic acids derived from the decay of the vegetable matters on the surface, or more quickly by ad- mixture with stable manure, the potash and phosphates of the sterile subsoil, marl, or under clay are brought into a condition available for vegetable nourishment, and the partly exhausted surface-soil is renovated by the admixture. Gar- deners and farmers have found by experience that the grad- ual mixture of marls, or heavy marl-like subsoils, together with the use of materials to furnish humus, is the best practical mode of making them useful in renovating the exhausted surface-soil. This result of the experience of the practical farmer shows, no doubt, how these marls may be most profitably used. It is said by some observers that admixture of caustic lime with the marls will aid in the separation of the potash and phos- phoric acid; and it is known that to calcine them in mixture with lime or carbonate of lime and calcium chloride, such as is al)bundantly thrown away in the bitter water which drains off from salt at the salt-works, will fully liberate the potash; but this is unavailable on a large scale because of its cost, and consequently, it appears that the best probable method of using these rich marly clays, marls, or subsoils on the ex- hausted soil, is to spread them on the surface, mixed prefer- ably with slaked lime, and then to sow the land with clover, which, after a year or two of growth and pasturage, will supply to the soil, when plowed in, a large amount of vege- table matter to form humus, which will greatly aid in the chemical decomposition of the marl, and in improving the productiveness of the soil, 6i COMPARATIVE VIEWS OF THE COMPOSITION As may be inferred from their composition, some of these Kentucky marly clays may be employed in making some forms ot pottery, terra-cotta, &c., especially the so-called stone- ware, which is hard and compact because of the softening or partial fusion of the clay in the heat of the kiln, and which is glazed with common salt only. For the various forms of /eri-a- co//a, and architectural appliances and ornaments, the tints which some of these clays assume on burning would make them more appropriate. Ground and calcined with a proper proportion of lime, several of these marly clays, especially those containing much alkali, would no doubt make good Portland cement, the most durable of water cements; used in large structures, mixed with more or less sand, gravel, and pebbles, &c., as the Ba/on of the French. When the oxide of iron is in large proportion in a hydrated state, these clays may be advantageously employed as materi- als for painting, as pigments of various tints of yellow, orange, red, and brown, having the names of boles. ochres, red chalk, terra sienna, umber, &c., &c. These, when calcined, assume otheJr, colors-the yellows changing to reds, &c., &c. They are among the cheapest and most durable of common pig- ments. The published Kentucky Geological Reports give several examples of such ferruginous clays. 62