where, to supply the potential energy required by the organism to construct the tissues and maintain the body, the temperature of the body being about the same in all climates. Fat does not stand alone in this regard, except under such extraordinary circumstances as those referred to. Carbohydrates of various kinds contribute to the same functions as fat, under ordinary conditions, but they do not suffice to maintain the stamina of the organism to the highest degree anywhere without the assistance of, or being supplemented by, some kind of fat.
A correct appreciation of the benefit of fat food in the Arctic regions serves as an index to its advantages under other conditions. It is not limited to blubber, 'toodnoo' or oil, even among the Laplanders. It includes the solid portions of reindeer, seal and other meat. And this in its composition doubtless compares favorably with the choicest cuts of beef and mutton, which consist of 20 to 30 per cent, of fat; or possibly with good bacon or ham, 35 to 50 per cent. Good butter, it need hardly be said, is almost wholly fat—85 to 90 per cent.
Of approximate stamina and exemption from tuberculosis, it is not far fetched to refer to the history of most of the North American Indians, before the cultivation of cereals was introduced by the white settlers. Their food was almost exclusively the fat game which they hunted and killed in such a manner as to retain the blood. Of the wonderful physical strength and endurance of those savages, their history of them furnishes many examples. And the earliest records of consumption among them are contemporary with the attempted methods of civilizing them—inducing them to leave their tents and live in houses; restricting their game supply and supplying them with an excess of farinaceous food. They have ceased to be a hardy race and tuberculosis is common among them. The Gauchos of the South American pampas, who live almost exclusively upon fat animal food, are alike remarkable for their extraordinary stamina. The flesh-eating Mahometans of India are described by historians as being the most powerful, active-minded and hardy race of human beings in the world, presenting the widest possible contrast in physical development to the rice-eating and feeble Hindoos, of whom but few reach the age of forty years.
A striking example of what appears to be the result of a change from an almost exclusive fat meat diet to one largely farinaceous, in relation with tuberculosis, is afforded by the history of the New Zealanders, who, until about fifty years ago, were cannibals, eating their captives in war, but who besides consumed an enormous amount of fat pork. Dogs also composed a part of their dietary, and fish to some extent. They were remarkable for their physical development and exemption from tubercular diseases. But soon after the introduction of the potato as a staple food, at about the time mentioned,
