CHRISTIAN COUNTY. 159 



On Prairie Fork of Bear creek, tea miles south of Taylorville, the 

 ■washings on the hillsides exhibit at the top soft brown clay, and below 

 clay -with many small rounded pebbles. On the North Pork of the 

 Sangamon, one mile west of the east county liue, the river bluff is fifty 

 feet high, the upper portion of blue and dark-brown clay with sand and 

 pebbles; below there is a loose mass of sand aud pebbles, sometimes 

 cemented into a rough sandy conglomerate, at times sufficiently firm 

 and regular to make rough walls. Below this there is a dark colored 

 bed of finely comminuted sand and clay. Two miles further down 

 stream there is a low bluff of dark drift clay with pebbles aud small 

 bowlders at the bottom aud brown clay at the top At this place I 

 observed a quantity of bituminous shale, a little coal and some frag- 

 ments of limestone, all associated with the drift. 



The drift bowlders in this county are generally small, aud their char- 

 acter and composition various. Among them may be found greenstone, 

 quartzite, granite, sienite, epidote rock, corals from the Devonian and 

 limestone from the Silurian, but no peculiar drift fossils. 



At Pana, the I. C. E. E., passing through a mound, exhibits the follow- 

 ing section: 



Ft In. 



1. Soil and subsoil * 18 



2. Ash-brown clay 8 



3. Brown clay and small ronnded pebbles 15 



This section is similar to what may be found in all the mounds of this 

 part of the State. 



Coal Measures. 



This formation as seen in this county embraces a thickness of about 

 230 feet, in which are visible two coal seams, only one of which is of 

 workable thickness. These measures underlay the whole of the county, 

 although there are no outcrops in the south-west, nor do we find any in 

 the north-east quarter of the county, they being restricted to a small 

 district south of Pana, to Locust Pork, to South Pork for ten miles up 

 the stream from the west county line ; on North Fork for three miles 

 from the west line of the county, and one other outcrop between the 

 forks. The deep drift deposits cover the rocks in other places. These 

 rocks belong to the upper Coal Measures, aud their position in my upper 

 Coal Measure section is from No. 12 to No. 32 inclusive. 



The highest rocks (geologically speaking) are the beds south of Pana 

 at or near White's coal bank, of which the following is a section : 



Ft. In. 



1. Drift of clay, pebbles, etc 23 



2. Clay shale 10 



3. Blue and bituminous shale, part quite calcareous, passing into a dark colored lime- 



stone. -i 



