CRAWFORD COUNTY. 243 



county. It has been named the Erie shale by Dr. Newberry. Although 

 this shale has not been observed in outcrop at but one place in the coun- 

 ty, it is believed to occupy a belt of flat land intervening between the 

 outcropping edge of the Cleveland shale and that of the black slate. It 

 was struck in a well at twenty-eight feet, by Mr John Shumaker, N. E. J 

 section 26, Polk. Pieces thrown out of this well have a somewhat firm 

 and rock-like aspect. It glitters in the sun as if with minute scales of 

 mica, and is specked as if with coal. 



The Huron Shale. — This conspicuous formation occupies a belt about 

 six or eight miles wide, running north and south across the center of the 

 county. The city of Bucyrus is just within its western edge. It under- 

 lies portions of Chatfield and Cranberry, and all of Liberty and Whet- 

 stone townships. Although it may be called a conspicuous geological 

 horizon, yet not an exposure of it is known to occur in Crawford county. 

 It is met with sometimes within the area mentioned, in drilling wells, 

 and its presence is then evinced by the offensive odor of the water ob- 

 tained, or by the escape of inflammable gas. In general, wherever the 

 Huron shale underlies the Drift, there is a belt of sulphur springs and 

 gas wells. Such sulphur springs occur at Annapolis and in the vicinity 

 of New Washington. At the latter place wells dug to the rock emitted 

 a gas, which accidentally took fire and caused considerable alarm by the 

 violence of the flame. They were immediately filled by the owners. On 

 Joseph Kniseley's land, section 26, Sandusky township, is an unusual 

 assemblage of natural gas springs. The gas accompanies the rising 

 water, and is sufficient to serve for illumination, for which it was used 

 for some years. A funnel placed over one of these springs so as to con- 

 fine the gas, supported a flame continuously for two years. 



Olenlangy Shale. — Below the Huron shale, which is black, tough, and 

 bituminous, is a thickness of about thirty feet of a bluish and more sec- 

 tile shale, containing less bituminous matter. It sometimes is inter- 

 stratified through its whole perpendicular extent with bituminous beds, 

 like those of the Huron shale. It has afforded no fossils, but holds occa- 

 sional thin beds of impure blue limestone. It lies on the top of the blue 

 limestone quarried in the western part of the county. It is not visible 

 in Crawford county, but is favorably exposed in Marion and Delaware 

 counties along the Olentangy Creek* On the geological map of the 

 county it is named "Hamilton group" by Dr. Newberry. 



Corniferous Limestone. — This name has been applied to the limestones 

 intervening between the foregoing shales and the Oriskany sandstone 



* See Geology of Delaware County. 



