842 N. M. FENNEMAN 



glacier became very short. Those situated some miles down 

 the valley contain many rounded bowlders, for the obvious rea- 

 son that many of these have traveled far. Between the moraines 

 of great angular fragments and the ice, are newer ridges whose 

 constitution is in striking contrast with that of the outer ridges. 

 These newer deposits contain fragments of the same order of 

 size as those contained in the older ridges, but intermixed with 

 them are stones of all smaller sizes. In these ridges, often cap- 

 ping the several fragments or lying in masses at the very sum- 

 mit, are quantities of mingled mud and gravel so fresh that they 

 bear almost no evidence of having been washed by the rains of 

 a single season. They resemble nothing so much as the fresh 

 dump from a great steam shovel. On the north side of the 

 glacier such a ridge rises from forty to fifty feet above the present 

 level of the ice, showing that the surface of the glacier has wasted 

 by at least that amount since the ridge was formed. The unwashed 

 character of its summit makes it difficult to admit that more than 

 a single season has passed since its first exposure to subaerial 

 weathering. This necessitates the conclusion that the glacier 

 has wasted at least forty or fifty feet during the past summer. 



The recent contraction of the glacier is further evidenced by 

 the exposure of ice in one of the fresh morainic ridges now well 

 separated from the body of the glacier (Fig. 3). Super- 

 ficially this ridge differs not at all from any other moraine of 

 recent formation. Except for the fortunate section which 

 reveals its core, it would appear to be built of a framework of 

 huge fragments, from among which the finer materials have been 

 but partly removed by surface erosion. The section, apparently 

 due to stream erosion, exposes a surface of perhaps twenty or 

 thirty square yards of ice. The position of the stratification 

 planes, dipping toward the head of the glacier, agrees with the 

 supposition that these ice masses may still be in place, having 

 been covered and protected by the abundant debris at the ice 

 front. A second ridge of similar character, only partly sepa- 

 rated from the glacier and several hundred feet within the first 

 ridge, is plainly the result of the present summer's melting. The 

 front of the ice was early in the season completely covered with 



