124 GEOLOGY OF ILLINOIS. 



between the Spiller coal two miles north of Marion and the limestone 

 that usually overlays coal No. 9. This limestone was met with on the 

 S. B. (!) qr. of sec. 22, T. 7 S, E. 4 E, about two miles a little south of east 

 of Frankfort, and from its nearest outcrop in Williamson county, which 

 was at Dr. Smith's old place about two miles and a half south-east of 

 Corinth, its trend seems to be nearly north-west, though it probably 

 bends to the northward before reaching the west line of the county. 

 It should be found on the Big or Little Muddy's, but owing to the exces- 

 sive rains of the past season no examinations could be made on these 

 streams while I was at work in this county. 



At Mrs. Ewing's place, ou the S. W. qr. of sec. 23, T. 7 S., B. 4 E., 

 the following beds were found, that must overlay the limestone above 

 named : 



Ft. In. 



Sandy micaceous shale 10 to 15 



Band of ferruginous conglomerate 1 



Bituminous shale 3 to 4 



Thin coal 6 



Brown sandy shale with fossil plants 3 to 4 



Dark -blue micaceous shale 5 



Brown shale - 30 to 15 



The coal noted in the above section varies in thickness in this vicinity 

 from two to eighteen inches, and is probably a local seam overlaying 

 the limestone which outcrops about half a mile to the west of this point. 

 This limestone is here a hard even bedded rock of a steel-gray or 

 brownish-gray color, weathering to a yellowish -drab. It dips gently to 

 the north eastward with the fall of the small branch on which it is 

 found, and only about three feet in thickness of its upper layers could 

 be seen. The only fossils we noticed in it were Athyris subtilita, Spirifer 

 Kneatus, Rhynchonella Osogensis, and Prodiictus longispinus. Coal No. 9 

 will probably be found a few feet below the limestone; but as it is 

 usually too thin to be of any economical value, there is no inducement 

 to expend either capital or labor in its development. Coal No. 7 

 (Spiller's coal) should be found here at a depth of 125 to 150 feet below 

 this limestone, and will be the first one of the main coals to be reached 

 by a shaft in this county. 



About two miles and a half west of Benton, and a mile south of the 

 DuQuoin road, there is an outcrop of soft ferruginous sandstone overlaid 

 by sandy shale. The beds exposed were about fifteen feet in thickness, 

 and at one point a thin coal was found below the sandstone. The rocks 

 here have a strong resemblance to those seen in the vicinity of Shaw's 

 shaft north of Coriuth in Williamson county, and if the equivalents of 

 them, the Carlinville limestone will be found not very far below the 

 level of the Big Muddy river. A similar bed of sandstone outcrops on 

 Dr. Hickmajs's place a mile and a half south-west of Benton, and the 



