THE BRANDON GLACIAL LAKE. 379 



tively, westward hj the Big- Sloug-h and southward across the Tiger Hills 

 moraine; second, from the whole lake, when these parts became confluent, 

 by the southward one of these outlets, namely, the gap where the Souris 

 now flows through the Tiger Hills; and, third, by confluence with Lake 

 Agassiz, when this was permitted by the recession of the ice. Much modi- 

 fied drift was probably lirouglit into the Brandon Lake hj drainage along 

 the course of the Little Saskatchewan, and it is significant that in the line 

 of continuation of the valley of that stream the jilain between Kenmay 

 and Brandon is crossed by a broad watercourse, which was evidently 

 eroded after this lake became merged in Lake Agassiz, thereby falling 

 nearly 100 feet below its former level when outflowing through Langs 

 Valley, but before the Assinilwine had cut its broad valley through this 

 delta. More exactly, as before noted, this watercourse seems referable to 

 the Herman h stage of Lake Agassiz, and the similar watercourse about 20 

 feet lower, passing through the west and south parts of Brandon, was prob- 

 ably formed during the Herman hh stage. During tliese two stages of the 

 lake the principal expanse of the Assiniboine delta was formed, Ij'ing only 

 slightly below the levels which the lake then had. 



At the time of formation of the Herman hh beach the Assiniboine 

 had already eroded a deep and wide valley in its delta at Brandon, and 

 as Lake Agassiz sank to successive lower levels this erosion continued, 

 cutting at least the lower part of the great valley 200 to 300 feet deep, in 

 which tliis river flows above Brandon, and wearing its channel to a nearly 

 equal depth through its own delta. The Canadian Pacific Railway crosses 

 the Assiniboine about 2 miles east of Brandon, near the di\'ision between the 

 main area of its delta in Lake Agassiz and the deep portion of its upper 

 valley. There the high land on each side of the river recedes, allowing 

 the descent to the sti-eam to be made by easy grades on each side and 

 supplying upon the gradual slope south of the river the beautiful site of 

 Brandon. No other point so fa^'orable for this crossing exists within 60 

 miles to the east or west, where the river flows in a deeper and narrower 

 valley. The greater part of this delta was modified drift derived from the 

 melting ice-sheet on the upper part of the basin of the Assiniboine and on 

 Riding Mountain, being carried down from the latter area by the Bu-d- 



