290 l;. BELL — GLACIAL PHENOMENA EN CANADA. 



The general outline of the gnat Archean area of the northeastern part of 

 the continent and Greenland approaches an elliptical form, but its superficial 

 continuity is broken in place- by shallow water or thin basins of Paleozoic 

 ks. 'The whole area (excluding Greenland) has only a moderate eleva- 

 tion above the sea: and, on the Large scale, it may be considered as nearly 

 level, being interrupted only in a few parte by heights which can be called 

 mountains. Yet every part of it which is not buried under the drift is broken 

 up into isolated rounded hummocks, a condition which is best described as 

 mammillated. The whole vast country has been planed down bo thoroughly 

 and deeply that few traces of the preglacial surface remain. The northern 

 part of the coast range of eastern Labrador, probably the highest ridge in 

 Canada east oi the Rocky Mountains, has not Keen glaciated except locally 

 in the valleys. It consists of Laurentian gneiss, like the rest of Labrador, 

 but without a close examination one would not recognize in the peaks, ser- 

 rated ridges, and earthy looking slopes of these mountains the same rock- 

 that constitute the bar,e, hard, flattened domes of the Laurentides elsewhere. 

 This range was probably much more elevated during the ice age and formed 

 the Btarting point of the glaciers, which flowed northward into CJngava bay 

 and westward into Hudson's hay. From the latter their course was still 

 westward and Bouthwestward to the western holder of the Archean region 

 and far beyond it in the Saskatchewan and .Mackenzie river basins. 



In the Gaspe* peninsula, too, there appears to be an absence of travelled 

 bowlders, if not of general glaciation, as was pointed out by the writer in 



L859. In most parts of the region affected by the drift tin ly fragments 



of the preglacial Burface bo far discovered consist of limited beds of liguile 

 and trace- of the channels of rivers cut in the solid rocks, which are usually 

 buried beneath the till. 



In the valley of the Athabasca river towards the periphery of the 

 glaciated region, where the ice-sheet was probably much thinner than over 



the Laurentian area to the east of it. the valley- hear evidence of preglacial 



origin. Some facts in this connection are given in the Geological Survey 



report by the writer for 1882. The depth and grandeur of the valley of the 



little Clearwater river have been remarked by all travellers in these parts. 

 Thi- Btream flows westward and joins the Athabasca aboul 150 miles Bouth 

 of Athabasca lake. Above the junction the bed and valley of the main 

 river are only large enough to accommodate the present stream, bul below it 



the valley immediately Income- ahoiit a mile wide, with a level, w led in- 

 tervale Ltwe. n the hank-, while the present river has a width of only one 



or two hundred yards. The Clearwater has steep hanks from 500 to 600 

 feel high, with a width of about a mile between their k brinks. In my report 

 for l >,v '_'. I stated that "the valleys of both the Athabasca and Clearwater, 

 ae far a- thej are excavated in the Cretaceous and Devonian strata, may be 



