GLACIERS OF THE CANADIAN ROCKIES AND SELKIRKS. 59 



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blocks of quartzite, sandstone, and schist tumultuously heaped into a ridge 30 to 40 

 feet high. The sandstone and schist have undergone considerable disintegration, 

 in place, forming more or less soil which supports a growth of moss, shrubs, 

 spruce, and fir. The rings of growth, in the spruce and fir of the Lake Louise 

 Valley, were found to average 0.884 rnm., and, in the case of the averages for 

 individual trees, to range from 0.5 1 mm. to 1.26 mm. As the tree matures the new 

 rings are excessively thin; owing to the reduction in the relative amount of leaf 

 surface, the scant precipitation, the short growing season, and the lack of direct 

 sun light in a deep valley with a north-south trend. The largest tree found upon 

 this moraine gave a circumference of 221 cm., at a distance of 50 cm. from the 

 base, and should be approximately 400 years old. The material of this moraine 

 is arranged in two main heaps, between which the glacial brook passes, that 

 upon the eastern side having come from Mt. Lefroy and that upon the west 

 from Victoria. After the formation of the moraine the glacier retreated up 

 the valley to a point greater than that occupied by the present nose. 



From 300 to 800 feet farther down the valley there occurs the second of this 

 type of moraines, the blocks consisting very largely of quartzite, lichen-covered 

 and moss-grown, but not disintegrated. As in the case of the preceding moraine 

 the blocks are disposed in two heaps, upon either side of the glacial brook, 

 the bulk of it lying to the west, where it forms an oblique ridge 700 to 800 feet 

 long, with a maximum breadth of 300 feet and a height of 70 to 80 feet. Made 

 up of such coarse blocks and with no filling of sand, gravel, or clay the whole 

 presents a very imposing mass and impresses one with the possible importance of 

 glaciers as geological agents. The largest block seen had split in falling, measured 

 31x25x15 feet, and was estimated to weigh 970 tons. The blocks are generally 

 sharp and angular and have not been subjected to stream or ice action. They were 

 carried either upon the ice or within it and show almost no signs of ice abrasion. 

 An occasional single face is glaciated but in such a way as to show that this was 

 done when, in its original position, it formed the face of the cliff. Owing to the 

 lack of soil the growth of shrubs and trees is scant. The largest spruce seen 

 upon the moraine itself was estimated to be 450 years old, while another just 

 beyond the outer edge was estimated at 580 years. Upon the side of Mt. Whyte 

 just at the line of plates, there is a large collection of similar blocks, and appar- 

 ently of equal age, which appear to have become stranded here while the others 

 were undergoing transportation. It should be noted that the present Victoria 

 is entirely incapable of making such a moraine now, no matter how prolonged 

 the halt. The present terminal moraine, and the oldest of the series to be 

 described, are essentially alike but very different from these great block, or 

 bear-den moraines. The cliffs which contributed the bulk of the material, 

 so far as we may judge from their favorable situation and the location of the 

 blocks, have a north-northwest trend and the blocks fell from them to the 

 eastward. 



Down the valley, a distance of one-quarter of a mile, there occurs a double 

 detrital cone, derived from the opposite mountain slopes of Mt. Whyte and Castle 



