KANKAKEE AND IROQUOIS COUNTIES. 233 



In descending the river, the next outcrop seen is at Kankakee City, where, 

 beneath the bridge, twelve or fifteen feet of thin-bedded, light buff, vesicular 

 limestones ara exposed, which are sometimes quarried for the linings of wells, for 

 foundations, or for road-material. At the foot of Court street, large flags are 

 quarried, with small quantities of thicker stone, from an outcrop of thin-bedded? 

 compact to vesicular, bluish-gray limestones, with partings of greenish clay. 

 The surfaces of these layers often show crinoidal fragments, and occasionally 

 present small crystals or fragments of pyrite. The same beds continue up 

 Soldier creek, and are largely quarried, above the Wilmington road, where the 

 greater amount of covering has prevented the disintegration of the clay-layers, 

 so that the beds appear to be more solid. At this, point, a slight southerly dip 

 is apparent. The broad floor of the quarry is strongly marked by a double 

 system of joints, the best developed of which bears by compass due northwest 

 and southeast ; the other set is not regular. The same beds present a nearly 

 continuous outcrop down the river, through section 24, township 31 north, 

 range 11 east, and are underlaid, in section 23, by a few feet of cellular lime- 

 stone, containing casts of crinoids and other fossils, which is locally used for 

 fences. In section 16, we pass down to very compact, though rather thin- 

 bedded limestone, every way fitted for building purposes, for which it is 

 occasionally used. These beds apparently correspond with those quarried at 

 Joliet, in Will county. The same beds are known to exist, at slight depths 

 below the surface, over much of the southern part of this township, and have 

 been opened for local use at two or three points. They are also worked in a 

 small quarry on the west side of section 7, township 30 north, range 11 east 

 (the fractional township), where from eight to ten feet of valuable stone have 

 been opened in the prairie. A fine specimen of Spirifer crispus was the only 

 fossil seen here. 



Apparently near this level, though possibly a little above it, at Manteno, a 

 small quarry has been opened in an outcrop of thinly and irregularly bedded 

 limestone, which is said to be easily broken up by the frost. It contains many 

 cavities lined with calcite, and a few Orthocerata are occasionally met with. 



In descending the river, below the quarries, in section 16, we find the beds 

 becoming thinner and more vesicular, and finally passing gradually into more 

 impure and strongly ferruginous layers, and decomposing readily. It is this 

 feature which has made the valley broader and the slopes of the banks more 

 gentle in this locality. 



Cincinnati Group. Just at the county-line, we pass below the Niagara 

 group, and find about ten feet of the sandy calcareous shales of the Cincinnati 

 group exposed above low-water mark. This is the only outcrop of rocks of this 

 group within the county, but the two ranges of townships, west of this point, 

 are almost entirely underlaid by them at slight depths. The prairie surface 

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