258 The Parallel Drift-tliUs of Western Netv Yorh. 



portion. As to the superficial layer, including the lai'ger crys- 

 talline boulders, we cannot be so certain. 



But conceding that it was deposited by glacial action, we have 

 still to account for its peculiar topographical features. Such ex- 

 tensive deposits of drift, are, perhaps, not veiy uncommon, but 

 such peculiar regularity of deposition is certainly seldom met 

 with, at least in this country. Sir Willi;im Logan has reported 

 something similar in Canada, and as will be shown presently, a 

 parallel is found in Scotland. 



That this great drift deposit cannot be classed with terminal 

 or lateral moraines, is evident at once from its general composi- 

 tion, for it differs from them in almost every essential particular. 

 It must of necessity be termed the moraine 2^r of onde, — the ground 

 moraine. 



Why it came to assume its present shape, instead of that of a 

 broad sheet of nearly uniform thickness, will, I think, become 

 evident when we consider the jjoints from which the glacier 

 forming it came, and the forces which influenced that glaciers 

 flow in this locality. 



In a recently published ai'ticle Professor Hitchcock says, "The 

 latest generalizations indicate that some part of the Labrador 

 Peninsula may be considered as the center from which the ice 

 Inis radiated over the Dominion of Canada and the northern 

 United States, east of the Eocky Mountains ***** 

 most of this territory exhibits a southwesterly course of glacia- 

 tion * * * ^yj,]] gliown over the highlands between 

 Hudson's Bay and the St. LaAvrence Valley, the valley itself, 

 western New York" etc.; "while in eastern New York and the 

 Champlain and Hudson Valleys, the course is southerly." 



Professor Newberry, in an article on the Surface Geology of 

 Ohio, presents a very interesting and satisfactory general sum- 

 mary of the glacial phenomena throughout the Avliole lake re- 

 gion. He believes that the period opened with the formation 

 of local glaciers on the Laurentian Mountains, which crept down 

 and began the excavation of the present lake basins in what Avas 

 then the valley of a river which drained this portion of the 

 continent, floAving through the present Mohawk Valley. That, 

 as the cold increased, these local glaciers partially coalesced, 

 forming a many-lobed ice-sheet, which moved rad'atingly from 



