ADVANCE AND RETREAT OF CANADIAN GLACIERS 735 



frozen into the ice and forming a sort of conglomerate. The surface 

 is thickly covered also. The ice thus loaded and protected seems 

 entirely stagnant, neither moving nor melting. The main body of the 

 ice, however, was clean-surfaced. Several recessional moraines 

 showed its retreat. 



Similarly a glacier extending northward from Emerald Mountain 

 showed several recessional moraines on its western side, while the 

 eastern portion, which was buried in talus, appeared to be stationary. 



At the head of this same Laughing Fall Valley lies a lake, about 

 a mile in length. Its outlet is over rock, its eastern and northern 

 sides are of rock, while its western side is formed by a debris-laden 

 glacier. Besides the ice is a brook, the lower course of which is 

 arched over by snow. The snow patch ends in the lake, and portions 

 of it break off and float away like small icebergs. The glacier 

 appears to be advanced as far as it ever was. There is no moraine 

 in front of it, and no debris could be seen in the water of the lake. 

 Since the water of the lake is remarkably clear, any debris that had 

 been dropped in it could have been distinguished. 



The debris of this glacier is apparently derived directly from the 

 mountain behind it, without the assistance of cliff glaciers. This 

 point, in which these three Yoho glaciers are alike, is an important 

 difference between them and the glaciers of the first group. Although 

 resulting in a preservation of the ice in both cases, it is in the Yoho 

 an exceptional and unusual occurrence, while among the glaciers 

 first described the debris covering comes as a necessary part of their 

 mode of origin. 



The Lake Louise sheet of the Canadian Survey map, though 

 accurate near the railroad, is in the Yoho Valley entirely a work of 

 imagination. The lake at the head of I^aughing Valley, and five 

 large glaciers are omitted entirely, while the position of mountains 

 and slopes of valleys are inaccurate. The sketch map (Fig. 2) accom- 

 panying this paper is adapted from this sheet. 



GLACIERS OF THE SECOND GROUP 



Glaciers of the Yoho Valley. — At the head of Yoho Valley is the 

 Wapta glacier (Fig. 10). This glacier is fed by a great and yet 

 unmapped snow-field. The glacier itself is broad and short. Its 



