350 THE ICE AGE IN NORTH AMERICA. 



sents a bordering plain of sand and gravel, deposited, in the 

 manner above described, about the base of the great terminal 

 moraine, and decreasing in height as the distance increases 

 from the base to the south. Similar deposits characterize 

 the southern flanks of the kettle-moraine of Wisconsin and 

 its extensions both east and west. Several such are crossed 

 upon the railroad from Elkhorn to Eagle, in Walworth county, 

 Wis., where the hills of the moraines are to the north, and 

 much low, swampy land lies to the south and east. It is evi- 

 dent that the ice remained here just long enough for the cur- 

 rents of water which swept down from the moraine to fill the 

 depression with sand and gravel from its base down to the 

 line of the railroad, whereupon the retreat of the ice-front 

 allowed the course of the drainage to change, and to build 

 up deltas at some other point. 



The discussion of kaines is not complete without directing 

 attention to the fact that they do not by any means always 

 occupy a continuous slope from the highlands to the glacial 

 margin ; and this has an important bearing upon the ques- 

 tion of the mode of their formation, and their connection 

 with ice-barriers and with ice-channels. Frequently, when 

 following a kame down a gentle incline or over a level plain, 

 it will be found that, on coming to a transverse valley one 

 hundred and fifty or two hundred feet in depth, and perhaps 

 more, the kame is not interrupted, but it descends into the 

 valley on one side, and ascends on the other to the level plain 

 beyond. This feature of the kames across the Merrimack 

 Eiver above Lawrence, Mass., has already been referred to. 

 and it early attracted my attention, and was fully described 

 in one of my first papers on the subject.* 



Another interesting illustration of this phenomenon, and 

 one which reveals the ingenuity of the investigator, is re- 

 lated by Professor Stone respecting the kame which crosses 

 Schoodic Lake in eastern Maine. He had followed the kame 



* See " Some Remarkable Gravel Ridges " ; also, " The Kames and Moraines 

 of New England " ; also, map p. 338. , 



