154 GEOLOGY OF ILLINOIS. 



No. 2 of this section is the bed which is here worked as a building stone. It 

 is extremely soft and easily worked when first taken out, but is said to harden 

 on exposure to the weather. It is considerably used for general building pur- 

 poses in the vicinity. Below the quarry, exposures of shaly sandstone and 

 arenaceous shales occur along the banks of the creek, wherever it touches the 

 bluffs which edge the narrow bottom, as far as the county line, a distance of 

 about one mile, and probably continue to appear along the lower course of the 

 branch in Scott county. Above the quarry, there are no prominent outcrops, 

 although the same beds undoubtedly occur in the hill sides. At one point only, 

 in a ravine running down to the creek, in the northeast part of section 29, I 

 observed indications of the sandstone in the material thrown out of an artificial 

 excavation. 



Passing southward from this point, along the western side of the county, the 

 next exposure of the Coal Measures is on the south side of Sandy creek, in the 

 western part of section 16, township 14, range 11, on the land of Mr. S. Can- 

 non. The outcrop is only of limited extent, and consists of light colored, 

 rather argillaceous shale, overlaid by sandstone. The vertical thicknecs of the 

 shale is altogether, perhaps, four feet. The sandstone was only seen in tumb- 

 ling masses, with, at one point, a glimpse of the rock in place. No fossils were 

 collected in this locality. 



Proceeding up the ravine of Sandy creek, in the bottom of one of the side 

 ravines opening from the northward, in the northwest quarter of section 11, 

 township 14, range 11, I observed a large, tumbling mass of light colored, brit- 

 tle limestone, which evidently had not been far removed from its original bed. 

 Similar masses occur in one or two of the side ravines of this stream and its 

 tributaries in this vicinity, but no good outcrop of beds in place occur along 

 this part of its course. In the western half of section 9, township 14, range 

 10, there are exposures of light colored, fossiliferous limestone, which has been 

 quarried in several places on the bluffs on the south side of the creek. Under- 

 neath this limestone, at one or two points, a little west of the center of the 

 section, appear exposures of a light colored shale, apparently entirely destitute 

 of fossil remains. The whole exposed thickness of the shale is about ten feet ; 

 that of the limestone is not so easily ascertained, as the exposures are not con- 

 tinuous, and the whole thickness is not exposed at any one place. Judging, 

 however, from the difference of level in the different exposures, it would seem 

 to be not less than that of the shale, and probably much more. 



A little farther up stream, near the center of the section, at the crossing of 

 the railroad (St. Louis, Jacksonville and Chicago), a shaft has been sunk about 

 half way up the side of the bluff. It penetrates the Drift and underlying beds, 

 to the depth of about eighty feet, and afforded the following section, accord- 

 ing to the statement of parties present during the excavation : 



