Glaciers of the Canadian Rockies and Selkirks; (Smithsonian Expedition of 1904) (Paperback)

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1907 edition. Excerpt: ...third of the glacier. Upon either side of the third stream these ridges are double for a considerable distance. Toward the western end of the glacier these moraines are neither so well defined nor so continuous and, owing to the deflection of the streams to the eastward, by the ancient moraine, swing around into a position almost parallel with the frontal. By the blending of these lateral moraines upon adjacent streams the single ridges resulting become the medial moraines of the piedmont glacier, and the outermost laterals of the two marginal streams become the laterals of the unified glacier. At the eastern end of the glacier the first stream is so short that the right lateral of the second ice stream constitutes the right lateral of the glacier as a whole. If the first stream ever extended to the front then this lateral moraine was originally a medial. A deep depression, snowfilled in 1904, separates it from the double debris cone and from the mountain spur shown upon the map. At the western side of the glacier, owing to the deflection eastward of the ice streams, there is no distinction to be made between the lateral and the frontal moraine. They end in a peculiar series of short closely pressed ridges, slightly concave outward. Since a glacier of this kind cannot be said to have an end, the term frontal may be more appropriately applied to the rock debris that is being dumped along the united extremities of the individual ice streams. Were the glacier to begin a uniform retreat from its present position, there would be left a ridge of angular rock debris, over three miles in length, marking the shape and present position of the front. Inside of this would be left upon the valley floor the debris which now mantles the surface of the...