170 THE ICE AGE IN NORTH AMERICA. 



Through the southeastern corner of Highland county, and 

 the northwestern corner of Adams, the terminal accumula- 

 tions are less marked than in Ross county ; still, their bound- 

 ary can be accurately and easily determined. It approaches 

 the Ohio River, in the vicinity of Ripley and Higginsport in 

 Brown county, and crosses it from Clermont county, entering 

 Kentucky half a mile north of the line between Campbell 

 and Pendleton counties in that State. Cincinnati was cov- 

 ered with ice during a portion of the period. There are un- 

 doubted glacial deposits within the bounds of the city at the 

 railroad station at Walnut Hills, and near Avondale, at a 

 height of about four hundred feet above the river. At North 

 Bend, twenty miles below Cincinnati, the tunnel of the rail- 

 road leading from the Ohio to the Great Miami River is 

 through an indubitable glacial accumulation which rises two 

 hundred feet above the river. The northwestern part of 

 Boone county, Ky., was also covered with the ice to a dis- 

 tance of several miles south of the Ohio River. 



Through Indiana the glacial boundary, after following 

 the Ohio River to within ten or twelve miles of Louisville, 

 Ky., suddenly bends to the north, leaving a large 'triangular 

 portion of the State unglaciated. The base of this ungla- 

 ciated triangle extends from Louisville to the Illinois line, 

 and its apex is about thirty miles south of Indianapolis. 

 The exact course of this part of the boundary is along a line 

 running from the neighborhood of Louisville northward 

 through Clark, Scott, Jackson, Bartholomew, and Brown 

 counties to Martinsville in Morgan county, where it again 

 turns west and south nearly parallel with, and west of, the 

 West Fork of White River, through Owen, Greene, Knox, 

 Gibson, and Posey counties, crossing the Wabash River 

 into Illinois, near New Harmony, the seat of Owen's cele- 

 brated socialistic experiment. 



In Illinois the line continues in a southwesterly direction 

 through White, Gallatin, Saline, and Williamson counties, 

 where it reaches its most southern limit near the northern 

 boundary of Johnson county, fifty or sixty miles north of 



