We should have attached more importance, no doubt, in the early stages of reconnaissance, to the East Rongbuk Glacier had we not been deceived in two ways by appearances. It had been an early impression left in my mind, at all events, by what we saw from Shiling, that a deep valley came down to the East as the R.G.S. map suggests, draining into the Arun and having the North-east arete of Everest as its right bank at the start. Further, the head of this valley seemed to be, as one would expect, the gap between Everest and the first peak to the North which itself has also an Eastern arm to form the left bank of such a valley. The impression was confirmed not only by an excellent view from a hill above Ponglet (two days before Tingri and about 35 miles North of Everest), but by all nearer and more recent views of the mountains East of the Rongbuk Glacier. The idea that a glacier running parallel to the Rongbuk started from the slopes of Everest itself and came so far to turn Westward in the end hardly occurred to us at this time. From anything we had seen there was no place for such a glacier, and it was almost unimaginable that the great mountain range running North from the North Col, Chang La, was in no part a true watershed. We saw the East Rongbuk Glacier stretching away to the East and perceived also a bay to the South. But how, if this bay were of any importance, could the glacier stream be so small? We had found it too large to cross, it is true, late in the afternoon of our first expedition, but only just too large; and again it seems now an unbelievable fact that so large an area of ice should give so small a volume of water. The glacier streams are remarkably small in all the country we explored, but this one far more surprisingly small than any other we saw. [Illustration: SUMMIT OF MOUNT EVEREST AND SOUTH PEAK from the Island, West Rongbuk Glacier.]