732 



I. H. OGILVIE 



than in ordinary talus slopes, for in falling 2,000 feet or more the 

 bowlders often break and gain unweathered surfaces. But in shape 

 there is a conspicuous difference between subglacial and superglacial 

 fragments. The superglacial material retains its angular form, and 

 is dropped in the terminal moraine without scratches, while the sub- 

 -^lacial material is worn and grooved. The result is that those parts 

 of the moraine which are composed of superglacial debris resemble 

 talus, and can be distinguished from it only by their topography. 



Fig. 7. — Cliff glacier of Mount Victoria, and the side of the \''ictoria glacier. 



The glaciers described above represent the type in this region. 

 Several other glaciers of the same type were seen by the writer, but 

 only one of them lay west of the continental divide. This one is at 

 the head of Lake Oesa. 



The steep front characteristic of these glaciers is a feature that has 

 hitherto been recorded only in the case of high-latitude glaciers. 

 Steep fronts are characteristic of both cliff and valley glaciers in the 

 Canadian Rockies, and are due to different causes in the two cases. 

 In the cliff glaciers the steep front of the ends comes from the periodic 

 breaking off of the front of the glacier, the broken end falling over a 

 cliff and leaving a vertical ice face on the glacier (Fig. 7). It occasion- 

 ally happens that the slopes of mountains on which cliff glaciers rest 

 are bounded by cliffs on several sides. In such cases the cliff glaciers 



