was the biggest and heaviest man in the expedition: "the man whom we had least expected to fail."
The rations were of two kinds. The Barrier (B) ration was that which was used on the Barrier during the outward journey towards the Pole. The Summit (S) ration was the result of our experiments on the Winter Journey. I expect it is the best ration which has been used to date, and consisted of biscuits 16, pemmican 12, butter 2, cocoa 0.57, sugar 3 and tea 0.86 ounces; total 34.43 ounces daily per man.
The twelve men who went forward started this S ration at the foot of the Beardmore, and it was this ration which was left in all depôts to see them home. It was much more satisfying than the Barrier ration, and men could not have eaten so much when leading ponies or driving dogs in the early stages of summer Barrier sledging: but man-hauling is a different business altogether from leading ponies or driving dogs.
It is calculated that the body requires certain proportions of fat, carbohydrates and proteins to do certain work under certain conditions: but just what the absolute quantities are is not ascertained. The work of the Polar Party was laborious: the temperatures (the most important of the conditions) varied from comparative warmth up and down the glacier to an average of about −20° in the rarefied air of the plateau. The temperatures met by them on their return over the Barrier were not really low for more than a week, and then there came quite commonly minus thirties during the day with a further drop to minus forties at night, when for a time the sun was below the horizon. These temperatures, which are not very terrible to men who are fresh and whose clothing is new, were ghastly to these men who had striven night and day almost ceaselessly for four months on, as I maintain, insufficient food. Did these temperatures kill them?
Undoubtedly the low temperatures caused their death, inasmuch as they would have lived had the temperatures remained high. But Evans would not have lived: he died before the low temperatures occurred. What killed Evans? And why did the other men weaken as they did, though