2 COAL MEASUEES. 



underground drifting, but in this country seams of less than eighteen 

 inches are generally neglected, except "when they can be worked by 

 stripping the coal along the outcrop of the seam. 



The following detailed section has been constructed from the most 

 satisfactory outcrops examined in various portions of the State, and is 

 given as an approximately correct description of the most important 

 strata recognized in the progress of the Geological Survey. They are 

 numbered from the bottom upward and may be briefly described in 

 detail as follows, commencing with the highest beds of the upper meas- 

 ures as they were found developed in Effingham and some of the adja- 

 cent counties. The best exposures of these upper coals and associated 

 strata were found on the upper course of the Kaskaskia and its tributa- 

 ries, and to the east and south-east including the counties adjacent to 

 the Wabash river, from Clark county on the north to the south line of 

 White county, where the limestone separating the upper and lower 

 measures is found outcropping at New Haven, on the lower Wabash : 



Ft. In. 



No. 95. The highest strata recognized in the district above described was found by llr. 



Brpadhead, in Effingham county, and consists of sandstone and sandy shale, upper 



part gray, middle brown, with fragments of fossil plants 50 



No. 94 Bituminous shales and septaria, with Pleurotomaria sphcerxdata, Spirifer piano-con- 



vexus, Ehynchonella osagensis, Natitilus occidentalism N.ferratus, etc G 



No. 93. Dark clay shales 4 



No. 92. Dark ash-brown sbaJy and nodular limestone, containing Jlyalina sub-quadrata, 

 Aviculopecten occidentalis, Bellerophon Montjortianus, Bdmondia, Leda, Macrodon, 



etc 1 6 



No. 91. Blue and olive shales 5 



No. 90. Gray sandstones and sandy shales 26 



No. 89. Thin coal 



No. 88. Fire clay 5 



No. 87. Buff sandstone 12 



No. 86. Clay shale with bands-of fossiliferous iron ore containing Leda bella-striata, Astartella 

 vera, Nucula ventricosa, Spirifer piano -convexus, Chonetes Flemingii, Myalina sub- 

 qxuzdrata, Macrocheilus inhabilis, PUurotomaria Grayvilleiisis, Bellerophon Mont- 



fortianus, B. carboiiarius, and Orthoceras Kushensis 35 



No. 85. Bituminous shales and pyritiferous limestone with argillaceous shales containing 



silicious wood 9 



No. 84. Gray pyritiferous sandstone 30 to 40 



No. 83. Shales with fucoids 40 



No. 82. Gray limestone with Fusulina cylindrica? Athyris siibtilita, Spirifer cameratus, S. 



plano-convexus, etc 4 to 8 



No. 81. Calcareous shales with Orthis carbonaria and Productus longispinus very abundant . . 1 6 

 No. 80. Coal No. .16, "Nelson's coal in Effingham, and the coal on the Erubarras. in Coles Co..l to 3 



No. 79. Fire clay 1 to 3 



No. 78. Sandstone and shales 80 to 90 



No. 77. Bituminous shale 2 



No. 76. Coal No. 15, "Shelby coal" 1 to 3 



No. 75. Fire clay 2 to 5 



No. 74. Buff limestone ". ,. 4 



No. 73. Sandstone and shales ; 15 to 50 



No. 72. Sbales partly calcareous 10 to 15 



No. 71. "Calcareo -bituminous sbales passing into shelly bituminous limestone, fossils abun- 

 dant, Eitomphalus sub-rugosus, Chonetes Flemingii, Productus eostatus, P. longis- 

 pinus, Hemipronites crassus, Eetzia punctuHfera, Lophophyllum prolifentm, Ortho- 

 ceras Pushensis, JEi-isocrimts typicus, Zeacrinus ? mucrospinus, and Peripristis 

 semicircitlaris ..2 to 4 



