1836.] 



FARMERS' REGISTER. 



557 



over with stately pine, oak. and hiekory, sloping 

 on their sides at an angle of 30 degrees, and bor- 

 dered with a naked prairie at 30 feet distance. 

 A surface of three inches depth composed of de- 

 cayed vegetation with a little sand, was removed, 

 when a stratum of red clay, 12 inches deep, was 

 exposed — (No. 1.) Next was a blue clay, 12 

 inches deep. (No. 2.) Next a dry pulverulent 

 substance, (No. 3,) of about the same depth, 

 which appears to be identical with No. 4, taken 

 from 12 inches below the surface of the naked 

 prairie adjoining. No. 5 was taken from imme- 

 diately above the latter, and six inches below the 

 surface sod of the naked prairie. No. 6 is a pul- 

 verized specimen of the dense substance that un- 

 derlies the whole of this section of country, and 

 was taken from immediately below No. 4. It is 

 deposited in strata of from four to six inches thick, 

 and is occasionally interspersed with strata of a 

 substance resembling No. 2. Wells or graves dug 

 on any of our upland, whatever may be the sur- 

 face soi 1 , invariably, at various depths, penetrate 

 this material, and it has not yet been pierced 

 through by our deer est wells. It seems, as I for- 

 merly stated, to form the basis of our rich black 

 soil. Though of a light color when first exposed 

 to the light, yet when slaked by the elements, 

 and mixed with sand, clay, and vegetable matter, 

 it becomes of a deep black, and accumulated in 

 our valleys by washing rains, constitutes our cane- 

 brake uplands. This quality of soil has, this past 

 season, produced 100 bushels of corn to the acre — 

 wheat 15 to 20 bushels, and cotton 1500 weight. 

 It was not injured by the severe drought in the 

 spring, nor the excessive rains in August. No. 7 

 is taken from the wall of the ditch cut through the 

 alluvial bottom of my field, six feet below the 

 surface. 



The specimens, except No. 6. when first taken 

 up. were coarsely granulated, moist and pasty, 

 easily mashed between the thumb and finger. 

 They were afterwards dried and pulverized tor 

 the more convenient transmission. 



The whole surface of the uplands lies rolling, 

 with gentle swells, and the substrata betray the 

 same inclination. The soft limestone frequently 

 crops out. at the surface, where it is dissolved by 

 the weather, and is washed to where it is mixed 

 with the vegetable matter of a lower level, and 

 loses its distinctive color. If carbonate of lime be 

 the sine qua non in the composition of rich dura- 

 ble soils, we have it in abundance. 



I have to thank you for the file of the Farmers' 

 Register, and your Essay on Calcareous Manures, 

 as well as Mr. Featherstonhaugh's report. It is 

 much to be regretted that Mr. F. did not direct his 

 investigations more with a view to the promotion 

 of agricultural science. The mystery of nature's 

 operations in producing food for animated beings, 

 the materials she works with, and the modes of 

 combining them, come legitimately under the 

 head of geology, and is to that science what phy- 

 siology is to anatomy; and in the course of im- 

 provement for which the present age is remarka- 

 ble, Ave may expect to see geology, chemistry, and 

 agriculture associated, and taught together in our 

 institutions of learning. 



N. D. SMITH. 



[The specimens described in the foregoing letter 

 were requested of our correspondent, and selected by 



him (with respect to their location in both prairie and 

 woodland,) according to our general directions. The 

 interesting, though too general information on this sub- 

 ject, furnished by a former letter from Dr. Smith, (page 

 273, Vol. III. Farm. Reg.) induced our seeking from 

 the same source what was more precise. It was sup- 

 posed, that specimens of soil and subsoil, taken in both 

 woodland and prairie, where there was an abrupt line 

 of separation, and where these different kinds of land, 

 preserving all their peculiar features, approached close- 

 ly to, or actually touched each other, would best serve 

 to prove, or disprove, the truth of our views of prairie 

 soils. The specimens were well chosen for the ob- 

 ject, and their respective proportions of calcareous in- 

 gredients, as tested by our analyses, furnish new and 

 strong supports of the doctrine maintained at length in 

 No. 6, that such differences in soils were the usual and 

 sufficient causes of the formation of prairies in some 

 regions, and their non-existence in others. These spe- 

 cimens show that a body of soil and subsoil, both not 

 much exceeding two feet in thickness, being destitute 

 of carbonate of lime, can sustain a growth of large and 

 flourishing trees, though the earth beneath is highly 

 calcareous; but that where the surface, and also the 

 lower beds, are calcareous, trees are no more seen, and 

 the land is a perfect prairie. 



The specimens described above, on being submitted 

 to chemical tests, gave the following results: 



From Woodland. 



100 parts contained of car- 

 bonate of lime — none. 

 - 27 



No. 1. Red clay, 



No. 2. Blue clay subsoil 



No. 3. Still lower, 



.} 



From Prairie land adjacent. 

 No. 5. (6 inches below the surface sod,) - - 28 



No. 4. Lower— (12 inches,) - - -58 



No. 6. General character of soft rock, (the "rotten 

 limestone" of Alabama,) which under- 

 lies the whole country, - - 77 

 No. 7. Alluvial soil — contained no carbonate of lime. 



From the Transactions of the Geological Society of Pennsyl- 

 vania. 



ACCOUNT OF THE TRAVERTIN DEPOSITED 

 BY THE WATERS OF THE SWEET SPRINGS, 

 IN ALLEGHANY COUNTY, IN THE STATE 

 OF VIRGINIA, AND OF AN ANCIENT TRA- 

 VERTIN DISCOVERED IN THE ADJACENT 

 HILLS. 



By G. W. Featherstonhaugh, Geologist to the 

 United States, Fellow of the Geological Societies of 

 London and Pennsylvania, &x. 



In a report lately made to government, and re- 

 cently published by order of both houses of con- 

 gress, I have at page 21 spoken of a rare, geologi- 

 cal phenomenon, in the valley of the Sweet 

 Springs, Virginia; the which, as it is connected 

 with the structure of the Alleghany ridges, I am 

 desirous of giving a more full description of, for 

 the transactions of the Geological Society of 

 Pennsylvania. 



The principal ridges of the Alleghany eleva- 

 tions have a general parallelism to each other, 

 and coming from the north, run in a S. S. W. di- 

 rection through the state of Virginia, until they 



