The party, Somervell, Crawford, and I, with fourteen porters (Wakefield was to be supply officer at Camp III), set out at 8 a.m. In spite of the hard frost of the previous night, the crust was far from bearing our weight; we sank up to our knees in almost every step, and two hours were taken in traversing the snowfield. At 10.15 a.m., Somervell, I, a porter, and Crawford, roped up in that order, began to work up the steep ice-slope, now covered with snow. It was clear that the three of us without loads must take the lead in turns stamping out the track for our porters. These men, after their immense efforts on the first and second attempts, had all volunteered to “go high,” as they said once more, and everything must be done to ease the terrible work of carrying the loads over the soft snow. No trace was found of our previous tracks, and we were soon arguing as to where exactly they might be as we slanted across the slope. It was remarkable that the snow adhered so well to the ice that we were able to get up without cutting steps. Everything was done by trenching the snow to induce it to come down if it would; every test gave a satisfactory result. Once this crucial place was passed, we plodded on without hesitation. If the snow would not come down where we had formerly encountered steep bare ice, a fortiori, above, on the gentler slopes, we had nothing to fear. The thought of an avalanche was dismissed from our minds. It was necessarily slow work forging our way through the deep snow, but the party was going extraordinarily well, and the porters were evidently determined to get on. Somervell gave us a long lead, and Crawford next, in spite of the handicap of shorter legs, struggled upwards in some of the worst snow we met until I relieved him. I found the effort at each step so great that no method of breathing I had formerly employed was adequate; it was necessary to pause after each lifting movement for a whole series of breaths, rapid at first and gradually slower, before the weight was transferred again to the other foot. About 1.30 p.m. I halted, and the porters, following on three separate ropes, soon came up with the leading party. We should have been glad to stay where we were for a long rest. But the hour was already late, and as Somervell was ready to take the lead again, we decided to push on. We were now about 400 feet below a conspicuous block of ice and 600 feet below Camp IV, still on the gentle slopes of the corridor. Somervell had advanced only 100 feet, rather up the slope than across it, and the last party of porters had barely begun to move up in the steps. The scene was peculiarly bright and windless, and as we rarely spoke, nothing was to be heard but the laboured panting of our lungs. This stillness was suddenly disturbed. We were startled by an ominous sound, sharp, arresting, violent, and yet somehow soft like an explosion of untamped gunpowder. I had never before on a mountain-side heard such a sound; but