BRITISH COLUMBIA AND ADJACENT REGIONS. 



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feet above the neighbouring river- valleys, or 5280 feet above the 

 level of the sea. Its summit has been heavily glaciated, the projecting 

 rocky masses being worn into ridges parallel to the direction of ice- 

 movement, the indicated direction of which is nearly parallel to a 

 bearing N. 29° W. to S. 29° E. If not due to the general glaciation, 

 these markings can have been caused only by ice from the coast- 

 ranges ; and though ice has flowed from these as from the other 

 mountain masses of the province during the later portion of the 

 glacial epoch, I believe the situation of Iron Mountain to be such as 

 to preclude altogether this mode of explanation. The mountains of 

 the coast-ranges are neither high enough nor so near as to supply a 

 body of ice capable of overriding it. 



On the plateau south of Kamloops glaciated surfaces have been 

 found in several places at an elevation of about 3200 feet above the 

 sea. The locality is far removed from any mountain-ranges capable 

 of giving rise to extensive glaciers, being situated in the very centre 

 of the interior plateau. The rocks are broadly ice-shaped and not 

 unfrequently polished, more rarely distinctly striated. The direction 

 of movement varies from S. 6° E. to S. 27° E. On another part of 

 the plateau, north of the course of the upper part of the Nicola 

 River between Stump and Douglas Lakes, at an elevation of about 

 3622 feet, are glacial traces similar to the last, consisting of polishing 

 and striation without fluting, having a general direction of S. 9° E. 

 Still another instance of this general glaciation is found on the 

 granite rocks near Chain Lake, between Lake Okanagan and the 

 Similkameen River, in latitude 49° 40' N. Here, as in the cases before 

 mentioned, the circumstances seem entirely to preclude any expla- 

 nation by local glaciers, as the portion of the plateau on which it 

 occurs is fully up to the general level, and surpassed only by a few 

 insignificant hills at a considerable distance. The rock-surfaces 

 are beautifully polished, and show striation varying in direction 

 between S. 20° E. and S. 28° E., but no deep grooving. The ele- 

 vation is 4075 feet. 



The Okanagan valley has been alluded to in the paper already 

 referred to as the most important southern gateway of the interior 

 plateau. The bottom of this valley, where it crosses the 49th 

 parallel, is about 860 feet above the sea-level. It is wide, and must 

 at one time have been much deeper, as its rocky floor is not now seen. 

 It occupies the axis of a general depression of some magnitude, and 

 appears to have carried the drainage of a great part of the interior 

 of British Columbia at a former period. This valley has probably 

 been subject to heavy ice-action during the time of general glaciation ; 

 but to what extent the features now found may be due to this, and 

 in how far to a subsequent period when, as a narrow arm of the 

 sea or of a great lake, it carried southward ice produced by glaciers 

 nearer the mountains, it is now difficult to ascertain. Glacial 

 striation was observed descending obliquely from the sides toward 

 the centre of the valley, and also in several places in the valley 

 itself, but in both cases without distinct grooving. The rocks of 

 the sides of the valley are often distinctly moutonnees ; and, as seen 



