It has been recorded in earlier chapters how in three days from the Base Camp they reached a height of 21,500 feet on the East Rongbuk Glacier. The cold was great and their hardships were unrelieved by the greater comfort of established camps enjoyed by those who followed the pioneers. From their accounts they were evidently affected a good deal by altitude before turning back with their work accomplished, and in spite of the cold they experienced the familiar phenomenon of lassitude so painfully and particularly noticeable on the glaciers when the sun makes itself felt. But on the whole they had been less affected by the want of air than was to be expected. They had this advantage—that they proceeded gradually; the distance to travel was long, but the ascent was never steep, and they found the upper glacier very lightly covered with snow; and it is heavy going and a steep ascent that most readily induce the more distressing symptoms of mountain-sickness. However, from the point of view of acclimatisation it was highly satisfactory that this party should have proceeded with so little delay to reach 21,000 feet. [Illustration: SERAC, EAST RONGBUK GLACIER. ] Meanwhile Somervell and I, chafing somewhat at our inactivity and with the idea that a long day on the mountains would do us good at this stage, on May 6 climbed a small peak above the left bank of the Rongbuk Glacier. It was a day of small misfortunes for me. As we were walking on the stony slopes in the early morning my triconni nails of hard steel slipped on a granite slab and I contrived to leave there an incredible amount of skin from the back of my right hand. And higher, as we worked along a broken ridge, a large boulder poised in unstable equilibrium slipped as I brushed it with my knee and fell on the big-toe joint so as to pinion my right foot. It was an awkward moment, for the place was steep; I just had strength to heave it over and down the mountain-side, and luckily no bones were broken. But walking was very painful afterwards, and perhaps this accident had something to do with the fatigue I felt as we neared the summit. On the lower slopes I had been going well enough and seemed fitter than Somervell; at 21,000 feet he was apparently no more fatigued than at 18,000 or 19,000 feet, while I could scarcely drag one leg after the other. And when we came back to camp I was surprisingly glad to take a little whisky in my tea. III I have said too much already about the early stage of acclimatisation: my excuse must be that much will depend upon this factor. The issue will depend no less on organisation and transport; and though this subject is General Bruce’s province, at all events so far as Camp III, I have a few words to add to what he has written.