On the following day we sledged on until we were close to the ice-mound already mentioned, and decided that as this mound commanded such a general view of the surrounding country, it must also be a conspicuous object to any one approaching the Drygalski Glacier by sea from the north. And so we decided that as we could find no trace of the "low, sloping shore"—as it was called on the Admiralty chart—we would make our depot at this spot.
We estimated that we still had 220 miles to travel from this depot on the Drygalski Glacier to the Magnetic Pole, and therefore it was necessary to make preparations for a journey there and back of at least 440 miles. We considered that with détours the journey might possibly amount to 500 miles.
Our first business, therefore, was to lay in a stock of provisions sufficient to last us for our journey, and after Mackay had killed some seals and Emperor penguins we started cooking our meat for the trip. Our calculation was that the total weight—when we depoted one sledge with spare equipment and all our geological specimens—would be 670 lb. But we were very doubtful whether we, in our stale and weakened condition, would be able to pull such a load.
We unpacked and examined both sledges, and found that of the two, the runners of the Duff sledge were the less damaged.
On the 14th we were still busy preparing for the great trek inland. Mackay was cooking meat, Mawson was employed in transferring the scientific instrument boxes and other things from the Christmas Tree sledge to the Duff sledge, while I was engaged on fixing up depot flags, writing letters to the commander of the Nimrod, Lieutenant Shackleton, and my family, and fixing up a milk-tin to serve as a post office on to the depot flag-pole.
When we were fully prepared the Christmas Tree sledge was dragged to the top of the ice-mound, where we cut trenches with our ice-axes in which to embed the runners of the sledge; then we fixed the runners into these grooves, piled the chipped ice on top, and then lashed the flag-pole about six feet high with the black flag displayed on the top of it very carefully to the sledge. We all felt quite sorry to part with the Christmas Tree sledge, which by this time seemed to us like a bit of home.
Anxious as we were to start for our dash towards the Pole, we were prevented by a furious blizzard from getting on our way until the 16th. Then we were delighted to find that, in consequence of our three days' rest we were able to pull our sledge with comparative ease.
Soon afterwards we reached another open tide-crack, and had to spend some time in going round it, and on the far side of this crack we encountered a large pressure ridge forming a high and steep slope which barred our advance. Its height was about eighty feet, but if we were to go on there was nothing to do but drag our sledge up the slope, a most exhausting work which was made more difficult still by the fact that this ice-slope was traversed by numerous crevasses.
At last we got up the slope, only to see in the dim light that a succession of similar slopes were ahead of us, becoming continually higher and steeper. The ice, too, became a perfect network of crevasses, some of which were partly open, but most of them covered with snow lids.
Suddenly, when crossing one of these lids, and just as he was about to reach firm ice on the other side, we heard a slight crash, and Mawson instantly disappeared. Fortunately the toggle at the end of his sledge-rope held, and he was left swinging in the empty space between the walls of the crevasse, being suspended by his harness attached to the sledge-rope.