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Show Settling of Snowcover Freshly fallen snow sinks fast. The night before April 2 there was a heavy snowfall and the cover was increased by 40 cm. Density was 0.06. By the evening of April 2 the fresh snow had settled to 27 cm; and at the end of 24 hours, to 21 cm, almost one half the initial thickness. The weather remained clear, with moderate frost. Such marked decreases in cover thickness are typical only of fresh falls; later, settling is much slower. The writer constructed a special device for measuring natural settling of snow at the site of a meteorological station during the winters 1938- 41. This device recorded continuous snow settling data. - 70 ~ T T- Y T F 7 .- r 7 Fig. 2. Diagram of Device for Recording Snow Settling. The receptacle part of this device is a light wooden ring set on the snow surface with a coarse mesh net, or gauze, stretched over it. A tin strip passes across the diameter of this ring, supported by a rib, and protrudes outside it. Both rings used had surface areas of 1960 cm2; one strip weighed 174 g, the other 139 g. The pressure exerted on the snow surface by these strips was 0.9 and 0.7 kg/ m2, respectively, the pressure of an average layer of loose snow 1 cm in thickness. The end of the tin strip ( 60 cm long) protruding outside the ring was connected by a thin soft wire ( 3) to a lever ( 4) which turned on an axis ( 5). A pen was fastened to one end of the lever, and a weight to balance the protruding tin strip was affixed to the other. On the lever thus balanced was a roller - 21- |