XII. Observations on pure ice and snow

The recent very severe winter afforded favourable opportunity and material for investigating some of the properties of ice and snow. The object of the following observations was to obtain information on the relative conductivity of ice and snow, the dilatation of pure ice, and its relative hardness or penetrability at various temperatures. The experiments on the conductivity of the ice were made as follows :—47 gallons of distilled water at a temperature of 48° F. were placed in a large circular iron tank, A, of the internal dimensions given on fig. 1.