DESCRIPTION OF GLACIER 



533 



discloses a furrowed character, due to the numerous crevasses on its 

 surface. 



Closer inspection reveals a pronouncedly hummocky appearance, with 

 broad depressions surrounded by steep ridges, above which rise many 

 conical or irregularly shaped peaks (figure 4). Again, broad domes 

 may characterize the surface. Some of these surface irregularities have 

 a difference in elevation of as much as one hundred feet. White ice 

 alternates with deep opaline blue ice and with dark patches of debris. 

 Rivulets of water traverse the surface ; some reach the margins of the 

 glacier, others disappear in cascades down pipelike holes or in deep 



Figure 4. — View of Ech/e of Glacier opposite Kennecott 

 Gray is debris ; black is melting icp. 



crevasses. Underneath is a continuous dull gurgle or roar of running 

 water, somewhat more noticeable near openings. The furrows which 

 mark the crevasses are found to be deep, elongated depressions formed 

 by the more rapid melting of the sides of the crevasses. Steep, elon- 

 gated ridges of ice separate them, and the relief is from 10 to 100 feet : 

 so that travel across them is in most places impossible. 



Both central and marginal crevasses were noted. The ]ower six 

 miles are relatively free from crevasses, but above this point, where the 

 width of the glacier is less, crevasses are the rule rather than the excep- 

 tion. Crevasses are most abundant, of course, where changes in dim-- 



