The scientific work to account for the sliding properties of snow and ice is not abundant. Osborne Reynolds suggested that a skate slid on ice owing to the lubrication caused by pressure-melting. Bowden and Hughes, after studying the measurements made by the last-named as physicist to our glaciological expedition to the Jungfraujoch in 1938, formed the opinion that this could not alone account for the action of ski sliding upon snow. I had reached a somewhat similar conclusion some years ago after a study of the structure of snow crystals on the surface of snow fields.

The preceding article by Mr Seligman has broken the ground for a review of what is known about the nature of friction on sledge runners, which is so vital an element in polar travel.

The aurora is a peculiar glow visible in cloud-free night sky. It is most frequently seen in high latitudes, but during very intense displays it may occur even in the tropics. The aurora in the northern hemisphere is called aurora borealis; in the southern aurora australis.

Spekk finger is the Norwegian name for a condition which is confined to people engaged in Arctic sealing. The word indicates that the disease has its origin from the blubber of seals and other mammals.

Every expedition which has employed dog transport will testify to the valiant work performed by their teams and will be ready with stories about their more notable dogs. They will tell of dog heroes who pulled a taut trace to their last breath, of dogs who lost heart early in the journey, of shy dogs and bold dogs, of those who were popular with the whole team and others against whom every fang was turned. Dog personality is, in fact, one of the first things a driver learns and the better he learns it the better driver he will be.