It seemed rather stuffy in the hut last night – I found it difficult to sleep, and noticed a good many others in like case. I found the temperature was only 50º, but that the small uptake on the stove pipe was closed. I think it would be good to have a renewal of air at bed time, but don’t quite know how to manage this.
It was calm all night and when I left the hut at 8.30. At 9 the wind suddenly rose to 40 m.p.h. and at the same moment the temperature rose 10º. The wind and temperature curves show this sudden simultaneous change more clearly than usual. The curious circumstance is that this blow comes out of a clear sky. This will be disturbing to our theories unless the wind drops again very soon.
The wind fell within an hour almost as suddenly as it had arisen; the temperature followed, only a little more gradually. One may well wonder how such a phenomenon is possible. In the middle of a period of placid calm and out of a clear sky there suddenly rushed upon one this volume of comparatively warm air; it has come and gone like the whirlwind.
Whence comes it and whither goeth?
Went round the bergs after lunch on ski – splendid surface and quite a good light.
We are now getting good records with the tide gauge after a great deal of trouble. Day has given much of his time to the matter, and after a good deal of discussion has pretty well mastered the principles. We brought a self-recording instrument from New Zealand, but this was passed over to Campbell. It has not been an easy matter to manufacture one for our own use. The wire from the bottom weight is led through a tube filled with paraffin as in Discovery days, and kept tight by a counter weight after passage through a block on a stanchion rising 6 feet above the floe.
In his first instrument Day arranged for this wire to pass around a pulley, the revolution of which actuated the pen of the recording drum. This should have been successful but for the difficulty of making good mechanical connection between the recorder and the pulley. Backlash caused an unreliable record, and this arrangement had to be abandoned. The motion of the wire was then made to actuate the recorder through a hinged lever, and this arrangement holds, but days and even weeks have been lost in grappling the difficulties of adjustment between the limits of the tide and those of the recording drum; then when all seemed well we found that the floe was not rising uniformly with the water. It is hung up by the beach ice. When we were considering the question of removing the whole apparatus to a more distant point, a fresh crack appeared between it and the shore, and on this ‘hinge’ the floe seems to be moving more freely.