PHYSICAL AND CLIMATAL CONDITIONS. 95 



the intermediate Leda clay, and the overlying sea-drift, 

 the latter implying, if rightly interpreted by him, a 

 subsidence of at least 1,300 feet.* McGee, in the reports 

 of the same survey ,-|* in describing the so-called " Colum- 

 bian " formation farther south, details facts of similar 

 import ; while in Chamberlain's map, in the same report, 

 the direction of striation leads to the same conclusion, 

 except that on the west side of the Appalachians the 

 arroios are reversed, making the glaciers move up the 

 mountain instead of down. Other citations might be 

 made to show that the geologists of the United States, 

 while still adhering to the hypothesis of a continental 

 glacier with a terminal moraine, stretching half-way 

 across North America, are accumulating facts in accord- 

 ance with the results worked out by Canadian geologists 

 in the Northern Appalachians, in the Laurentides and the 

 Western Cordillera, and which must eventually greatly 

 modify their views. 



In the same report of the Canadian Survey with the 

 observations of Dr. Ells, those of Mr. Low, in his report 

 on James's bay, show that on the east side of the bay the 

 glacial striae indicate a movement of ice to the westward 

 from the high Laurentian land east of the bay. Thus 

 the great Y-shaped Laurentian axis, while throwing off 

 ice to the St. Lawrence valley on the south-east, and to 

 the great plains then submerged on the south-west, was 

 also pouring off its ice into the interior basin of Hudson's 

 bay and into the arctic sea. It may, at the period of 

 extreme glaciation, have filled Hudson's bay with ice, and 

 there is evidence of a terminal moraine along the middle 

 of the bay, which may have belonged to the interglacial 



* Report U.S. Geol. Survey, Vol. VIII. 

 + Ih., 1885-6. 



