92 GEORGE MERCER DA "W SON ON THE 



an elevation of 7484 feet, while there is a considerable mountainous 

 area in the centre of the island, which surpasses 2000 feet in average 

 altitude. 



2. Vancouver Island and the Coast. 



a. Glaciation of Mock-surfaces. 



The glaciation of the rocks in the vicinity of Victoria, Vancouver 

 Island, is so well marked, and presents itself so immediately to any 

 one arriving in the locality, that it has been mentioned by most 

 writers on the country, and has been made the subject of remark 

 by several geologists*. The rocks protruding from the soil, and 

 projecting along the shores, are generally compact, coarser or fine- 

 grained diorites and felsites, bedded or intrusive, which, while offer- 

 ing great resistance to abrasion, are well suited to preserve forms 

 impressed on them. The direction of the ice-markings here has been 

 variously given — a circumstance arising, I believe, chiefly from a 

 want of attention to the magnetic variation, and the isolated 

 character of the observations made. I am now, however, in a 

 position to state, as the result of several hundred observations of the 

 course of the striation, that but one general direction of movement is 

 indicated in the whole south-eastern peninsula of Vancouver Island, 

 the average bearing of which is about S. 11° W.f, and from which, 

 except under certain special local circumstances mentioned below, 

 there is seldom a departure of more than a few degrees on either 

 side. At Sooke Eiver, fifteen miles west of Victoria, the only dis- 

 tinct grooves seen have a course S. 18° W., which agrees closely 

 with the above average direction, but is also parallel with that of 

 the hills bounding the river valley. Grooving and striation are 

 equally apparent at all elevations in the neighbourhood of Victoria, 

 from low- water mark upward. The summit of Mount Douglas, or 

 Cedar Hill, a rocky eminence 696 feet high, is quite distinctly 

 glaciated, the direction being, as nearly as can be ascertained, due 

 south. On looking northward from this hill on the wide expanse of 

 the Strait of Georgia, no higher land appears for about fifteen miles, 

 and then only as summits on scattered islands. Suitable localities 

 for observation at greater altitudes are wanting in the vicinity ; or 

 ice-work could no doubt be traced to a yet higher level. 



Rocks which, from their prominence, have been exposed to the 

 full force of the ice, are generally grooved and fluted in the most 

 remarkable manner (fig. 1), have been worn into boat-bottomed 

 shapes, marked with parallel hollows often a foot or more in depth 



* The glaciation of the southern part of Vancouver Island has been referred 

 to by the following gentlemen : — H. Bauerman, " On the Geology of the South- 

 eastern part of Vancouver Island," Quart. Journ. Geol. Soc. vol. xvi. p. 198. C. 

 Forbes, M.D., 'Prize Essay on Vancouver Island,' 1862. E. Brown. " On Sup- 

 posed absence of Drift on the Pacific Slope," Am. Journ. Sci. and Arts, 1870. 

 George Gibbs, " On Physical Geography of the North-western Boundary of the 

 United States," Journ. Am. Geog. Soc. 1874. A. R. 0. Selwyn, "Keport of 

 Progress, Geol. Survey of Canada," 1871-72, p. 52. 



t This and other bearings given are with reference to the true meridian. 



