238 GEOLOGY OF ILLINOIS. * 



Society of Philadelphia, vol. xii., p. 224. Although it is by 110 means 

 improbable that primeval man existed before the valley drift of this 

 region was deposited, yet we have no evidence going to show that he 

 was then so far civilized as to be able to work the native metals, or to 

 have acquired any knowledge of the use of money. 



8tr atigr aphical Geology. 



All the stratified rocks that appear above the lowest water levels in 

 this county belong to the Coal Measures, and comprise an aggregate 

 thickness of about 175 feet, including the horizons of coals No. 4 to 7, 

 inclusive. Three of these seams, Nos. 4, 6 and 7, are worked extensive- 

 ly, in various portions of the county, and have an aggregate thickness 

 of about twelve feet. 



The following section, constructed from the outcrops of the strata 

 along the Kickapoo creek and its branches, will illustrate the thickness 

 and relative position of the various coals in this county, and the rocks 

 with which they are associated : 



No. 1. Seam of smut, indicating a thin coal, or black shale 1 feet. 



No. 2. Soft brown sandstone, partly exposed 15 to 18 



No. 3. Gray limestone, upper portion nodular and impure 15 to 20 ' 



No. 4. Sandy and argillaceous shales 45 



No. 5. Bituminous shale 3 to 5 



No. 6. Coal, No. 7 1J to 3 



No. 7. Sandy shales 30 to 35 



No. 8. Light gray limestone, with fusulina 2 to 4 



No; 9. Bituminous slate and shale 1 to 2 



No. 10. Coal,No.6 3 to 5 



No. 11. Shales, argillaceous and sandy 20 to 35 



Horizon of coal No. 5. 



No. 12. Sandstone, partly ferruginous, passing upward into shale . 28 to 30 



No. 13. Bituminous and arg. shale, with iron stone concretions 5 to 8 



No. 14. CoalNo.4 4 to 5 " 



No. 15. Fire clay and septaria '. 2 to 3 " 



No. 16. Argillaceous and sandy shales 15 to 20 ' ' 



The three upper beds in the foregoing section, especially the limestone, 

 is well exposed at Mr. John Lonsdale's quarries, on the south side of the 

 Kickapoo valley, on section 14, town 8 north, range 7 east, (Limestone 

 township.) The lower layers of this limestone are quarried here both for 

 building stone and for burning into lime. This part of the bed affords 

 tolerably even layers, from four to eight inches thick, of fine-grained, 

 .compact, light-bluish gray limestone, that makes a very good building 

 stone and also a quicklime of fair quality. The upper portion of the bed 

 is in very uneven nodular layers ot an inch or two in thickness, and on 

 weathering becomes a loose mass of limestone pebbles, of about the 

 proper size for macadamizing material. Spirlfer lineatus and Athyriv 

 subtilita were the most common fossils found in these upper layers, .and 



