The Seward Glacier. 177 



A noticeal^le feature of the Alpine glaciers of Alaska is that 

 they expand on passing beyond the valleys through which they 

 flow and form delta-like accumulations of ice on the plains be- 

 low. This expansion takes place irrespective of the direction in 

 which the glaciers flow, and, so far as may be judged from the 

 many examples examined, is independent of the debris that 

 covers them. It should be remembered, however, that none of 

 the Alaskan glaciers thus far studied show marked inequalities 

 in the distribution of the moraines upon their surfaces. Should 

 one side of a glacier, on leaving a cailon, be heavily loaded with 

 marginal moraines, while the opposite border was unprotected, 

 it is to be presumed that a deflection of the ice would take place 

 similar to the change in direction recorded by the moraines 

 about Mono lake, California.* The normal tendency of ice, 

 when not confined, to expand in all directions and form a 

 plateau is illustrated on a grand scale by the Malaspina glacier. 



The most important ice-streams about Mount St. Elias and 

 Mount Cook are indicated on the map forming jDlate 8. The 

 Tindall, Guyot, and Libbey glaciers and the lower jDart of the 

 Agassiz glacier there represented are taken from a map pul)- 

 lished by H. W. Topham.f All of the other glaciers indicated 

 on the map were hastily surveyed during the present expedition 

 and are described to some extent in the accompanying narrative. 

 By far the most important of these is the one named the Seward 

 Glacier. 



The Seward Glacier is of the Alpine type, and is the largest 

 tributary of the Malaspina glacier. Its length is approximately 

 40 miles, and its width in the narrowest part, opposite Camp 

 fourteen, is about 3 miles. The main amphitheatre from which 

 its drainage is derived is north of Mount Owen and between 

 Mount Irving and Mount Logan. The general surface of the 

 broad level floor of this neve field has an elevation of approxi- 

 mately 5,000 feet. The snow from the northern and western 

 sides of Mount Irving, from the northern slope of Mount Owen, 

 and from numerous valleys and canons in the vast semicircle of 

 towering peaks joining these two mountains, unite to form the 

 great glacier. There is another amphitheatre between Mount 

 Owen and the Pinnacle pass cliiTs supplied principally by snows 



* Eighth Ann. Kept. TJ. S. Geol. Surv., 1889, part I, pp. 360-366. 

 t Alpine Journal, London, vol. IJtIV, 1887, pi. op. p. 359. 



