Quite an excitement last night. One of the ponies (the grey which I led last year and salved from the floe) either fell or tried to lie down in his stall, his head being lashed up to the stanchions on either side. In this condition he struggled and kicked till his body was twisted right round and his attitude extremely uncomfortable. Very luckily his struggles were heard almost at once, and his head ropes being cut, Oates got him on his feet again. He looked a good deal distressed at the time, but is now quite well again and has been out for his usual exercise.
Held Service as usual.
This afternoon went on ski around the bay and back across. Little or no wind; sky clear, temperature -25º. It was wonderfully mild considering the temperature – this sounds paradoxical, but the sensation of cold does not conform to the thermometer – it is obviously dependent on the wind and less obviously on the humidity of the air and the ice crystals floating in it. I cannot very clearly account for this effect, but as a matter of fact I have certainly felt colder in still air at -10º than I did to-day when the thermometer was down to -25º, other conditions apparently equal.
The amazing circumstance is that by no means can we measure the humidity, or indeed the precipitation or evaporation. I have just been discussing with Simpson the insuperable difficulties that stand in the way of experiment in this direction, since cold air can only hold the smallest quantities of moisture, and saturation covers an extremely small range of temperature.