62 GLACIERS OF THE CANADIAN ROCKIES AND SELKIRKS. 



be assumed to represent approximately the original valley before the ice invasion. 

 The lower portion, with the very steep walls and broad base, probably represents 

 that portion of the valley which was profoundly affected by the great ice stream 

 that so nearly filled the valley. The destruction of the strata necessary to 

 secure such a result was very probably accomplished by the disrupting power of 

 the ice, known as "plucking." 



e. Ancient till sheet. The rock debris was, in great part, delivered to the 

 Bow Glacier and carried beyond the mountains. The finer portions, consisting 

 of gravel, sand, and clay, with some cobbles and boulders, secured lodgment in 

 certain favorable places, particularly near the mouth of the valley, and com- 

 pacted by the great weight of ice formed the ground moraine, or sheet of till. 

 From 75 feet to 100 feet of this deposit have been exposed between the foot of 

 the lake and the Bow River, but the maximum thickness was very probably 

 much greater. It forms an irregular sheet, of unknown extent and thickness, 

 reaching up to and under the modern glacier, mantling the actual rock bottom 

 of the valley. It is entirely without stratification and the rock fragments are 

 largely bruised and scratched. The color, as seen in the exposed sections, is a 

 brownish-yellow, as the iron of the clay is being slowly oxydized. The more 

 deeply buried beds would, undoubtedly, show more of the bluish-gray, which 

 characterizes this material when it is fresh. 



CHAPTER IV. 



WENKCHEMNA GLACIER. 



i. GENERAL CHARACTERISTICS. 



NESTLING close in behind the northern base of that grand array of peaks for 

 which the Canadian Geographic Board has recently adopted the name Wenk- 

 chemna Group lies the Wenkchemna Glacier. The name is of Sioux origin, wik- 

 chemna signifying ten, and was given the glacier by Mr. S. E. S. Allen, in allusion to 

 its relation to the series of ten peaks upon which he bestowed the Indian numerals. 

 These peaks, the highest of which has been rechristened Mt. Deltaform, with 

 their high connecting ridges constitute here the great Continental Divide (plate 

 xxi). Between them and Mt. Temple lies a broad valley originally called "Deso- 

 lation Valley" by Wilcox, but now known as the Valley of the Ten Peaks. 

 The glacier occupies the southern half of the upper third of this valley, and 

 faces north, while the valley itself slopes eastward and then northeastward. 

 In a direct line it lies only about six miles south-southeast from the Victoria, 

 and may be reached by crossing the Mitre Pass, encircling the Horseshoe Glacier 

 at the head of Paradise Valley and entering the Valley of the Ten Peaks by the 

 Wastach Pass. The ordinary way of reaching the glacier, however, is from 

 the chalet at the foot of Lake Louise, over a good trail to Moraine Lake, 

 where a summer camp is maintained by the Canadian Pacific Railway. From 



