TOPOGRAPHY OF THE TRENCH 



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and of 1,120 feet at Kamloops. It flows, therefore, along a gradient of 

 3 feet per mile and is entrenched in the plateau to a depth varying from 

 2,300 to 3,200 feet. 



FiauRE 1. — Key Mat) of Area studied 



The upland plateau is characterized by gently undulating ground of 

 low relief, usually drift-covered and thickly timbered. A few bold peaks 



