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 lower end of a glacier, in spite of its rapid thawing, remained year after year at about the same point. Were we to attempt to describe the various observations that have been made with a view to determine the rate of glacial movement, we fear we should tax our reader's patience. Let us mention one or two illustrative facts. In the year 1827, M. Hugi built a very solid hut on the glacier of the lower Aar. In 1836 this hut was 4384 feet farther down the valley. Again, Professor Forbes gives an interesting account of a knapsack lost by a guide who fell into a crevass, one of those great chasms which are often observed in glaciers, which was recovered, ten years after, 4300 feet lower down. These facts, were there no others, would suffice to prove that the glaciers move onward at a slow but steady pace.

The surface of the glacier is rough and crumbling, and the traveller can walk upon it without fear of slipping; in some parts it is unbroken and undulating, but in others it is rent by yawning fissures many hundred feet in depth, one set of fissures sometimes crossing another at right angles, and so cutting up the ice in fantastic pinnacles and towers, that occasionally topple over with a terrific crash. The noises that proceed from the glacier cannot be properly described, and we can only vaguely compare the mysterious rumblings, growls, and cracklings that salute the traveller's ear to "noises in a swound."