THE VARIATIONS OF GLACIERS 317 



with some exceptions, among which are the glaciers southwest of 

 Mount Fairweather. 



The two glaciers of Taku Inlet were greatly' effected by the earth- 

 quakes of 1899, but are apparently making up a part of their losses. 

 {Davidson.) 



There are a large number of small glaciers at the heads of the 

 valleys tributary to Lake Chelan, Washington. One of these, at the 

 head of Railroad Creek, has retreated 200 feet in recent years; and 

 other glaciers in the neighborhood also have the appearance of being 

 in retreat. (Rusk.) 



The snowfall in the neighborhood of Mount Hood was unusually 

 large in the spring of 1904, as it has been for the last few years. 

 (Gorman.) Nevertheless, the Zigzag glacier on the west side of 

 Mount Hood seems to have become smaller since last year. (Knap p.) 

 The snowfall was very heavy in the Sierras this year; in the late sum- 

 mer the Lye'll glacier was still almost entirely snow-covered, and 

 deep drifts extended beyond the limit of the ice. It shows no definite 

 retreat since Professor Russell visited it in 1883. The accumulation 

 of snow seems to have been increasing during the last two or three 

 years, and "there is good reason for believing that the glacier is 

 slowly advancing." Lake Mono, at the foot of Mount Lyell, without 

 any outlet, has been slowly rising for many years. This seems to 

 ndicate an increase of precipitation in the region and may foreshadow 

 a general increase in the size of the glaciers. (Lee.) 



The Arapahoe glacier in Colorado shows no definite change since 

 last year. (Henderson.) The Hallet glacier, a little farther north, 

 has diminished in the last nine years, but there is no definite informa- 

 tion with regard to its more recent changes. (Mills.) 



The subject of glacial erosion is being vigorously attacked from 

 the standpoint of physiography. Mr. Willard D. Johnson 1 describes 

 the forms of old glacal valleys in the Sierras, dwelling especially 

 on the very low grade, occasionally even reversed, in the upper part 

 of the old glacial troughs. This form bears no relation to the profile 

 produced by stream erosion, and he therefore thinks that it is to be 

 accounted for by the erosion of the ice. He describes a descent into 



1 "The Profile of Maturity in Alpine Glacial Erosion," Journal of Geology, Vol. 

 XII (1904), pp. 569-78. 



