Page:Canadian Alpine Journal I, 2.djvu/111

Rh glaciers. The snow line crossing the glacier divides the upper surface into two regions which are designated as the névé, or region of perennial snow, and the dissipator, or that portion ordinarily free from snow during late summer and early autumn. Glaciers of the alpine type may receive tributaries from confluent valleys and these in turn receive tributary ice-streams. If we consider that the Mitre Glacier originates about the Mitre Pass, it receives a short, broad tributary from between Mitre Mountain and Mount Lefroy and together they join the Victoria, being compressed to about one-fifth of their breadth. Not infrequently it happens that the main glacial stream does not fill the valley and it is separated from its tributary streams by a precipice, or very steep slope over which the ice and snow are avalanched. The higher glacier is termed a hanging or cliff glacier, as seen upon the eastern shoulders of Mts. Victoria and Lefroy, and the glacier formed by the recementing of the ice fragments is spoken of as a reconstructed or regenerated. A very interesting example of such a regenerated glacier is formed from the hanging Lefroy, the fragments of which accumulate at the foot of the eastern wall of Mt. Lefroy, upon the upper western margin of the Mitre Glacier. There is piled up there, mainly in the summer, a mass of ice fragments, along with the ground-morainic material manufactured beneath the hanging glacier, which gives rise to a regenerated glacier resting upon the Mitre and which is more or less independent of it. The course of the regenerated Lefroy is across the Mitre, where it dumps upon the opposite side a great heap of ground moraine, while it is at the same time carried bodily toward the Victoria. Such a glacier, of which this is the best example known, has been more or less appropriately called parasitic.

(b) Piedmont Glaciers. When a well-nourished glacier of the alpine type flows from a valley out upon the adjacent plain it has a tendency to spread laterally