190 THE ICE AGE IN NORTH AMERICA. 



from the pole. For, in both these regions, though the soil 

 is frozen to a depth of several hundred feet, there are no indi- 

 cations of the presence of moving ice. Stagnant ice, however, 

 in many places takes the place of ordinary rocks. The expedi- 

 tion of Dawson to the Yukon in 1887 and that of Schwatka 

 and Hayes around Mt. St. Elias in 1892 demonstrated an 

 actual northward movement of ice. Dawson writes: 



In the Lewes and Pelly Valleys, traces of the movement of 

 heavy glacier-ice in northward or northwestward directions, 

 were observed in a number of cases, the grooving and furrow- 

 ing being equally well marked at the water-level and across 

 the summits of hills several hundred feet higher. The facts 

 are such as to lead to the belief that a more or less completely 

 confluent glacier-mass moved in a general northwesterly direc- 

 tion, from the mountainous districts south of the southern 

 source; of the Yukon, toward the less elevated country which 

 borders the lower river within the limits of Alaska. This ob- 

 servation, taken in connection with the evidence of the former 

 northward movement of glacier-ice in the arctic regions to the 

 east of the Mackenzie, appears to have very important bear- 

 ings on theories of general glaciation. f 



From all these facts it seems evident that the supposition 

 of a slight intensification of the present conditions so favor- 

 able to the production of glaciers in southeastern Alaska, 

 unravels the whole intricate web of glacial phenomena upon 

 the western coast of North America. 



The present formation of glaciers on the coast of south- 

 eastern Alaska is favored not so much by the coolness of the 

 climate as by the elevation of the mountains and the excess- 

 ive amount of precipitation, which, as before stated, is not 

 far from one hundred inches annually. There is no evidence 

 that the elevation of the coast has materially changed in 

 recent times. But it would require only a slight change in 

 the amount of precipitation, or a slight diminution of tem- 



* "Science," vol. xi, 1888, p. 186; "Geological Magazine," vol. lxx, 

 p. 347 et seq. 



f "Annual Report of the Geological Survey," L886, p. 56, R. 



