166 GEOLOGY OF ILLINOIS. 



Coal Measures. 



In this county there are exposures of about 175 feet of upper Coal 

 Measures, from No. 1 to No. 20, in which are included about two work- 

 able coals, Nos. I! and 15. The following is a condensed sectiou of the 

 various beds : 



Ft. In. 



1. Shales and sandstone, not recognized 



2. Limestone, dove colored 4 



3. Fire clay 2 



4. Shales passing into sandstone 30 



5. Limestone 4 



C. Shales at top, changing to argillaceous limestone 55 



7. Sandstone 4 to 40 



8. Shaly bituminous limestone and bitnminons shales 4 in. to 4 



9. Coal No. 15 18 in. to 3 



10. Fire-clay 15 in. to 5 



11. Limestone to 4 



12. Shales and sandstone 15 to 30 



13. Shales 



14. Calcareous shales 4 



15. Shales 



lfi Calcareous and bitnminons shales 2 



17. Coal, nearPaua 1C to 22 



18 Fireclay 5 



19. Sandy limestone 5 



20. Sandstone 



No. 1 of the above section was not recognized in this county, but 

 occurs in Moultrie. No. 2, five miles from Windsor, at a mill on Sand 

 creek, extends quite across and down stream for 200 feet. Four miles 

 north-east of Shelbyville, on and near the river, there is seen 4 to 4J 

 feet of limestone, the upper one foot sometimes shaly and fossiliferous, 

 containing Spirifer catneratus, Sp. lineatm, Spiriferina Kentuckensis, 

 Productus punctatus, Atlvyris subtilita, Hemipronites crassus, and criuoid 

 stems. The lower part is of a gray or dove color, and contains few 

 fossils. In the same neighborhood we find just beneath the fire-clay 

 (No. 3) 20 feet of sandy shales. At various places on the river there are 

 beds of. buff sandstone, making the entire thickness of sandstone and 

 shales (No. 4) amount to 30 feet. No. 5 is 4 inches of tough and very 

 coarse dark-gray limestone, mottled with dove colored spots, abounding 

 in fossils, including Myalina subquadrata, Pinna per-acuta, Allorisma 

 subcuneata, Prod. Prattenianus, Nautilus occideiitalis and Aviculopecten 

 occidentalis. At an old mill on the Kaskaskia river, four miles above 

 Shelbyville, it is found about three feet above low water; one mile up 

 stream it is seen sticking out of the bank at about the same distance 

 above the water ; at the latter place it is easily recognized, and very 

 good fossils can be procured ; but at the former it is not so firm, and the 

 fossils are almost blended with the rock itself. 



