292 Canadian Record of Science. 



very apparent from a geological point of view, as they do 

 not appear to coincide with any important lines of faulting. 

 The general plan of the foot-hills is repeated in the moun- 

 tains, on a large scale, and some of the cross valleys are con- 

 tinued quite through the foot-hills to the eastern plains, 

 while others again are found in the foot-hills, which do 

 not effect the mountains proper. It is probable that 

 lines of comminuted fracture or shattering of the rocks 

 may have originated these cross valleys, and it is possible 

 that they constituted an original drainage system for the 

 axis of elevation of the mountains, at a time anterior to that 

 at which the longitudinal valleys became deeply excavated, 

 and that some of them, by drawing to themselves the waters 

 of a number of the longitudinal streams, have succeeded in 

 maintaining their position as main waterways to the present 

 time. The great permanence of these main, transverse 

 drainage valleys is shown by the fact that the heights of 

 land between them, in the mountains, are often equal in 

 altitude to that of the main watershed. In no case, however, 

 in the region now described, does such a cross valley preserve 

 its characters so definitely across the entire range as to form 

 throughout a direct pass, or practicable route of travel, 

 though a near approach to this occurs in the North-Kootanie 

 Pass. The routes offering the greatest facility for crossing 

 the mountains, generally follow zig-zag courses, partly along 

 the longitudinal valleys, and seeking the lowest points at 

 which to cross the intervening mountain ridges. In conse- 

 quence of this, the lengths of the various transverse passes 

 are often considerably greater than the actual width of the 

 mountains. The following list enumerates the passes known 

 in this part of the range, with the length of each along the 

 direction of the trail, from the eastern to the western base 

 of the mountains. The altitude of each at the watershed or 

 main summit is given in the second column. 



Miles. Elevation of 

 watershed. 



1. South Kootanie or Boundary Pass, 66 7,100 



2. North Kootanie Pass, 48 6,150 



3. Crow Nest Pass 56 4,830 



4. North Fork Pass (1) 46 6/773 



