The Motion of the Nisqually Glacier. 109 



qually Glacier during the month of July. The position 

 of the end of the glacier was determined, and other of 

 its characteristics noted, in the hope that future observers 

 may be able to determine the changes that take place as 

 time goes on. 



The Nisqually Glacier takes its rise on the southern 

 rim of the crater, and for the first three miles of its course 

 has a direct southerly trend. The eastern side of its 

 trough is formed by a high conspicuous mass of rock 

 known as Gibraltar, and the western side by a relatively 

 low rocky spur separating it from the next large glacier 

 in that direction, the Kautz. Within the first three miles 

 the main neve stream makes a total descent of about 8,000 

 feet, and the surface is broken by enormous ice-falls and 

 faults. The average slope in this part is therefore about 

 thirty degrees, and the average width, including its west- 

 ern tributary, the Stevens Glacier, may be taken at a mile 

 and a quarter. At the end of this steep descent the grade 

 decreases to about ten degrees, and the ice here forms 

 a great crevassed field into which the Stevens Glacier falls 

 over a sheer cliff about 300 feet high. A little farther 

 on the ice becomes fairly consolidated and turns to the 

 southwest, maintaining this trend throughout the rest of 

 its course. A mile below the junction of the Stevens, the 

 glacier passes over an ice-fall, descending perhaps 500 

 feet in a quarter of a mile. The surface is here cut by 

 large transverse crevasses into an almost impassable mass 

 of seracs. Below the ice-fall the stream again consoli- 

 dates into a beautifully smooth glassy surface, with only 

 small fractures a few feet in width. The slope of this 

 part for over a mile is about eleven degrees. Marginal 

 crevasses now begin to show in a marked degree, and 

 these become larger and larger through lateral melting 

 as the snout is approached. The ice ends abruptly in a 

 very steep slope at an altitude of about 4,000 feet. 



The eastern side of the glacier is strewed with rock 

 and sand for a breadth of from 300 to 600 feet. The 

 spur of rock between the main stream and the Stevens 



