368 



THE ICE AGE m NORTH AMERICA. 



tucky hills, were large specimens of this same conglomerate 

 (one bowlder being nearly three feet in diameter), which had 

 been transported by glacial ice fully six hundred miles from 

 their native bed, and left to tell the story not only of their 

 own travels, but of other most interesting events connected 

 with the cause which transported them. These glacial de- 

 posits south of the Ohio are such as to make it certain that 

 the front of the continental glacier itself pushed, at some 

 points, seven or eight miles beyond the Ohio River; and it 

 is altogether probable that for a distance of fifty miles (or 



Fig. 108.— Conglomerate bowlder found in Boone County, Kentucky. (See text.) 



completely around the eastern, northern, and western sides of 

 the Kentucky peninsula formed by the great bend of the 

 river), the ice came down to the trough of the Ohio, and 

 crossed it so as completely to choke the channel, and form a 

 glacial dam high enough to raise the level of the water five 

 hundred and fifty feet — this being the height of the water- 

 shed to the south. The consequences following are inter- 

 esting to trace. 



The bottom of the Ohio River at Cincinnati is 432 feet 



