194 J. B. TYRRKLL GLACIAJ. PHENOMENA IN YUKON DISTRICT 



portion forming the valley of the Nordenskiold river, which joins the 

 Yukon a short distance above Five-fingers rapids, while the westerl}^ 

 valle}^ passes northward by Aishihik lake to Nisling river, down that 

 river to White river, and thence .down the White to the point where it 

 flows into the Yukon river. 



In addition to the trip outlined, a short time was spent farther north 

 on the Klondike river and its tributaries. 



Physiographic Features 



Toward the south this country is a mass of steep, rocky, ungraded 

 mountains, among which tower the giant peaks of Hubbard, Vancouver, 

 Logan, and Saint Elias. These mountains lie to the westward of the 

 great valley of the Lynn canal and Chilcat river, and form a range which 

 would appear to be quite distinct from the granitic " Coast range," which 

 forms the western wall of the continent farther south, in both Alaska 

 and British Columbia. In order to distinguish this range more clearly, 

 I propose for it the name "Chilcat range," associating it with one of the 

 most powerful tribes of Indians on the Alaskan coast. 



This range is bounded on the south and southwest by the Pacific 

 ocean and toward the north and northeast by the great Chilcat-Alsek 

 valley, Avhich extends inland from the western arm of the Lynn canal, 

 following more or less closely the line of contact of the granite to the 

 northeast and the schists and limestones to the southwest. The aver- 

 age width of the range is between 80 and 100 miles. 



Much of the range is buried in extensive snowfields, from which gla- 

 ciers radiate in all directions, both toward the coast and toward the in- 

 terior. A magnificent view of this country was obtained last summer 

 from the sunmiit of Farview mountain, a high peak southwest of Aishihik 

 lake, and it presented the appearance of a vast white plain, through which 

 the higher peaks rose in dark relief, mount Saint Elias appearing for a 

 few moments from beneath the clouds. It is thus avast snow-clad pla- 

 teau, lying close to the Pacific coast, in one of the regions of greatest 

 precipitation on the American continent. 



Farther north the countrA^is also mountainous, but the mountains are 

 much more rounded, their slopes are easier, and their sides show com- 

 paratively few broken, ungraded cliffs. As a rule, they rise from 3,000 

 to 4,000 feet above the bottoms of the deeper intervening valleys. Stand- 

 ing on one of the summits, a great number of similar mountains may be 

 seen on every side, all about the same height and probabl}' cut out of 

 the same extensive pre-Tertiary ]>eneplain. 



liakes, in some cases of large size, lie in the bottoms of the valleys ; 



