294 GEOLOGY OF ILLINOIS. 



vening strata were not exposed. In section 26, along Cedar Fork, this coal is 

 exposed a little above the bed of the creek. A section of the strata gave: 



FEET. 



1. Bluish-black limestone 8 to 10 



2. Black slate 6 in. to 2 



3. Coal 3 



A short distance up the stream, there appears to be a fault, and apparently 

 higher strata are exposed, and show the following succession : 



FEET. IN. 



1. Clay shale, not measured 



2. Sandstone, about 14 



3. Coal 1 1 



4. Fire-clay, passing into clay shale 2 



5. Black slate, not measured 



The strata on either side can be traced to within a few feet of the fault. 

 This, however, is not exposed, but a small gulch runs down the bluff at the 

 point where it probably exists. 



In section 13, township 8, range 1, there is another outcrop along Nigger 

 creek, which probably belongs to this seam. The exposed strata give the fol- 

 lowing section : 



FEET. IN. 



1. Clay shale, not measured 



2. Coal 10 



3. Shale, with a band of sandstone about 14 feet from the top 22 



4. Sandstone 1 6 



5. Black slate 1 6 



6. Coal, with some slate and clay shale 2 ft. 6 in. to 3 



7. Sandstone and arenaceous shale 3 4 



8. Coal from 1 in. to 2 



9. Fire-clay 1 



10. Sandstone, not measured 



The mines at this place have been abandoned for some time. The coal was 

 reported to be of poor quality, and mixed with slate. 



It is probable that everywhere in this county, this seam lies but a few feet 

 from the bottom of the Coal Measures, and wherever the lower strata are ex- 

 posed, they rest upon the Burlington limestone. Northwest of Monmouth, in 

 section 7, township 11, range 2, the rocks exposed in the bluff of Cedar creek 

 gave the following section : 



FEET. 



1. Slope, containing black slate, fire-clay and coal, not measured 



2. Sandstone, with thin beds of shale 10 



3. Burlington limestone, as far as exposed 33 



The coal mentioned in No. 1 of this section, is not likely to prove valuable, 

 as it lies too near the surface. 



