MAIN MORAINIC SYSTEM OF THE SCIOTO LOBE. 419 



or 20 feet deep. The wells penetrate till until they reach the water-bearing 

 gi-avel. The variability in depth at East Liberty is due mainly to varia- 

 tions in the altitude of the water-bearing gravel, but in part to the altitude 

 of the well mouth. Outcrops of rock occur along the inner slope of the 

 moraine west of these flowing wells, at altitudes 100 feet or more above 

 them, and the drift is thin for the breadth of a mile or more between these 

 outcrops and the morainic crest. Along the crest of the moraine the drift 

 is so thick that ravines and ordinary wells, which sometimes have a depth 

 of 40 feet, do not reach the rock, and the highest points probably have 100 

 feet or more of drift. Devonian shales occur to a limited extent beneath 

 the elevated portions of the moraine, but do not seem to form a continuous 

 belt. 



The supposed highest point in Ohio, as indicated above (p. 357), lies 

 between this moraine and Bellefontaine at the Hogue Summit on a 

 moraine of the Miami lobe, its altitude being given by F. C. Hill, of the 

 Ohio survey, as 1,540 feet. A point on the moraine under discussion at 

 New Jerusalem is, by aneroid, but 25 feet lower. This great height has 

 been ascribed to the presence of Devonian shales, and Mr. Hill estimated 

 their thickness to be 110 feet beneath the Hogue Summit and 136 feet 

 beneath New Jerusalem. In this estimate due allowance does not seem to 

 have been made for erosion and partial removal of the shale, for, as already 

 noted, 350 feet of drift was penetrated near the Hogue Summit. The most 

 elevated point at which the shale was noted is at New Jerusalem Falls, 

 one-half mile southeast of the village of that name, where its surface is 

 about 100 feet lower than at the New Jerusalem Summit, or 1,415 feet 

 above tide. The shales here have an exposure 60 to 75 feet in height 

 in the gorge below the falls The New Jerusalem Summit is a small 

 drift knoll covering but an acre or two, its highest point being 20 feet or 

 more above the bordering portions of the moraine Its highest point stands 

 about 26 feet higher than the well at Mr. Eastman's, where 350 feet of drift 

 occurs. Attention has already been called to the fact that, were the drift 

 removed from Logan County, the altitude of its highest points would fall 

 100 feet or more below that of the highest points of the rock strata in 

 southern Richland County, and that even with the increase in height pro- 

 duced by the drift, it is questionable if Logan County contains the highest 

 points in the State. 



