The abiding thought, therefore, after the first rush downwards on the steep slopes below the col contained a measure of solid satisfaction. We had now brought to an end our preliminary reconnaissance. Ahead of us was a new phase in our operations, and one which should hold in store for us the finest adventure of all, the climax of all reconnoitring expeditions, that advance which was to bring us as near to the summit as our strength would take us. As we plodded on, retracing our steps, some little satisfaction was highly acceptable. To the tired party even descent seemed laborious. We reached the edge of the glacier where we had come on to it at 5.30 p.m. But the march from there to our lower camp was both long and rough. Major Morshead, who had not been trained with Bullock and me to the pace of such expeditions, had kept up so far in the gamest fashion; but he was now much exhausted. The day ended with a series of little spurts, balancing over the snow-sprinkled boulders along and along the valley, in the dim misty moonlit scene, until at 2 o'clock in the morning we reached our lower camp, twenty-three hours after the early start. On August 20 we went down to Kharta for ten days' rest and reorganisation. The party was gathering there for the assault, in which all were to help to the best of their powers. Col. Howard-Bury and Mr. Wollaston were there; Dr. Heron came in on the following day, and a little later Major Wheeler. A conversation with this officer, who had been working in the Rongbuk Valley since Bullock and I had left it, was naturally of the highest interest, and he now confirmed what his sketch-map had suggested: that the glacier on to which we had looked down from Lhakpa La drained into the Rongbuk Valley. But this certain knowledge could have no bearing on our plans; we remained content with the way we had found and troubled our heads no more for the present about the East Rongbuk Glacier. CHAPTER XV THE ASSAULT