advantage in going higher than Finch and Bruce had done before using oxygen; whereas they had started using it at 21,000 feet, we intended to go up to our old camp at 25,000 feet without it, perhaps use a cylinder each up to 26,000 feet, and at all events start from that height for the summit with a full supply of four cylinders. If this was not the correct policy as laid down by Professor Dryer, it would at least be a valuable experiment. Our chief anxiety under these new conditions was to provide for the safety of our porters. We hoped that after fixing our fifth camp at 26,000 feet, at the earliest three days, hence on the fourth day of fine weather, the porters might be able to go down by themselves to the North Col in easy conditions; to guard against the danger of concealed crevasses there Crawford would meet them at the foot of the North Ridge to conduct them properly roped to Camp IV. As the supply officer at this camp he would also be able to superintend the descent over the first steep slope of certain porters who would go down from Camp IV without sleeping after carrying up their loads. But the North Col had first to be reached. With so much new snow to contend with we should hardly get there in one day. If we were to make the most of our chance in the interval of fair weather, we should lose no time in carrying up the loads for some part of the distance. It was decided therefore to begin this work on the following day, June 7. In the ascent to the North Col after the recent snowfall we considered that an avalanche was to be feared only in one place, the steep final slope below the shelf. There we could afford to run no risk; we must test the snow and be certain that it was safe before we could cross this slope. Probably we should be obliged to leave our loads below it, having gained, as a result of our day’s work, the great advantage of a track. An avalanche might also come down, we thought, on the first steep slope where the ascent began. Here it could do us no harm, and the behaviour of the snow on this slope would be a test of its condition.