Observations were carried out on each significant layer of the snow cover at Ottawa (lat. 45° 24′ N., long. 75° 43′ W.) on the thickness of the layer, and the density, grain size distribution and degree of bonding of the snow in each layer. A logarithmic dependence on time was found for the layer thickness, and the density and grain size distribution. The product of layer thickness times the corresponding snow density was found to be constant when no melting occurred.