96 GLACIERS OF THE CANADIAN ROCKIES AND SELKIRKS. 



forming an elongated tail, or trail, extending from the knob in the direction 

 of ice motion. In some cases a small quartz vein cuts across the surface in such 

 a way as to protect in its lee a strip of the softer rock. In front of the knobs 

 there is cut out, as a rule, a frontal groove lying at the base and curving around 

 laterally into two others, one upon either side, forming the lateral grooves. In 

 places where the ice acted with greater vigor, owing to the concentration of its 

 action, or where differences existed in the structure, or hardness, of the rock 

 there were cut out basins and U-shaped troughs, representing, in miniature, lake 

 basins and glaciated valleys. One basin, with perfectly smoothed sides and 

 bottom, had a length of 15 feet, a breadth of 6 feet, and a depth of 6 to 8 inches 

 below its lower rim. The greatest depth was located one-third of its length 

 from the upper end, indicating where the gouging action had been greatest. One 

 of the troughs was 1 1 to 1 2 feet across and 4 to 5 feet in depth. 



b. Bear-den moraines. Some 800 to 900 feet below the terminal moraine of 

 1887, or about 1,400 feet from the nose of the ice in 1904, there occurs a moraine 

 of the same general type as that described under this head in connection with 

 the Victoria. This consists of very massive blocks of quartzite, arranged in 

 a north to south ridge across the valley, having a breadth of about 400 feet and 

 a height above the general valley floor of 20 to 40 feet. The largest block 

 observed was measured by Messrs. Moseley and Todd and its dimensions, above 

 ground, were found to be about 107.5 by 28 by n feet, from which it was esti- 

 mated to weigh about 2,000 tons. A portion of this ridge is seen in plate xxxvi, 

 figure i , taken from one of the blocks of the moraine itself, looking toward the glacier 

 up the valley. The blocks are blackened with lichens, more or less moss-covered, 

 and carry enough soil to support considerable vegetation of a larger size. A spruce 

 growing upon the moraine had been cut and with a circumference of 128 centi- 

 meters gave 243 rings of growth. A hemlock, also upon the moraine, with a 

 circumference of 320 centimeters (50 centimeters from the base), was calculated 

 to be 447 years of age. This estimate was based upon the average breadth of the 

 annual rings of growth measured in the Illecillewaet and adjoining Asulkan 

 valleys. This average breadth was found to be 1.140 millimeters, as compared 

 with 0.884 millimeter in the Lake Louise Valley. 



From the outer edge of this moraine, 1,500 feet down the valley measured 

 along the stream, there begins another similar but larger moraine of the same 

 type. Starting from the spur of Glacier Crest which separates the Illecillewaet 

 and Asulkan valleys, the ridge swings out across the valley bearing N. 8 W., 

 and then swings around to N. 15 W. It is 200 to 300 feet across and some 50 to 

 60 feet above the valley floor, somewhat steeper toward the glacier. The blocks 

 are very coarse quartzites and schists, blackened with lichens, and presenting 

 angular outlines. The largest block noted was estimated to weigh 1,250 tons. 

 The usual filling of a moraine, gravel, sand, and clay, is practically absent. Upon 

 the eastern side, for a portion of its length, it is covered by a mass of broken 

 tree trunks which were swept from the side of Mt. Eagle by an avalanche (plate 

 xxxvn, figure i) some decades ago. Enough soil has accumulated about the rocks 



