It is by no means yet certain which is the best line of approach to the North Col. The route hitherto followed, viâ the East Rongbuk Glacier, is tedious and roundabout, but it has the advantage of being well sheltered from the wind, and, except for the final steep slopes beneath the col, safe under any conditions. Much more direct, however, and probably less arduous, is the approach from over the main Rongbuk Glacier. The line of ascent thence to the summit of the col presents no real difficulty, and, provided it is not found to be too exposed to the wind, is undoubtedly much safer, even after heavy snowfalls, than that previously followed. In the light of past experience one can hardly hope to count on good weather as an ally; adequate protection in the form of windproof clothing will enable the climber to face all but actual snowstorms. Climbing parties making the final assaults on the summit should be small, consisting of two men and no more. In the event of one man collapsing, his comrade, if at all up to scratch, should be able to get him down in safety. By so limiting the size of the parties, a number of attacks, each one as strong as if effected by a large and cumbersome team of, say, four, could be carried out. Again, in the case of small parties as suggested, mutual attention to each other’s oxygen outfit is possible and any necessary repair or adjustment more expeditiously made. The type of climber who should go farthest on Mount Everest would appear to be similar to that which best suits the Alps. Of the physical attributes necessary, the following points, in addition to what is usually termed perfect physical fitness, may be emphasised. In the rarefied atmosphere of high altitudes the larger the vital capacity the better. By the term “vital capacity” is meant the maximum amount of air an individual is able to expel from the lungs by voluntary effort after taking the deepest possible inspiration. Compared with the lean, spare type of individual, the thickset, often musclebound man, though possibly equal to an immense effort provided it is of short duration, is, as a rule, at a great disadvantage. The Expedition has also shown beyond all possible doubt that the tall man is less prone to become fatigued than one of shorter stature. Again, as is well known amongst mountaineers, the long-legged, short-trunk type of body is immensely superior to the short-legged, long-trunk type.