Page:Scott's Last Expedition, Volume 1.djvu/571

1911] as we have found, volumes of cold air at different temperatures are very loath to mix, the condition could not be relieved by any gradual process, but continues until the stream is released by some minor cause, when, the ball once started, a huge disturbance results. It seems to be generally held that warm air is passing polewards from the equator continuously at the high levels. It is this potentially warm air which, mixed by the disturbance with the cold air of the interior, gives to our winds so high a temperature.

Such is this theory—like its predecessor it is put up for cockshies, and doubtless by our balloon work or by some other observations it will be upset or modified. Meanwhile it is well to keep one's mind alive with such problems, which mark the road of advance.

Sunday, August 6.—Sunday with its usual routine. Hymn singing has become a point on which we begin to take some pride to ourselves. With our full attendance of singers we now get a grand volume of sound.

The day started overcast. Chalky is an excellent adjective to describe the appearance of our outlook when the light is much diffused and shadows poor; the scene is dull and flat.

In the afternoon the sky cleared, the moon over Erebus gave a straw colour to the dissipating clouds. This evening the air is full of ice crystals and a stratus forms again. This alternation of clouded and clear skies has been the routine for some time now and is accompanied by an absence of wind which is delightfully novel.

The blood of the Crozier Party, tested by Atkinson,