Influence of Quantity of Food.—The same, however, cannot be said of the quantity of food. It must be maintained without reservation that an abundant supply, a quantity even more than barely sufficient, a slight excess, is essential to the fullest development of the human powers, be they physical or mental. The belief that muscular strength and endur ance, or intellectual clearness and grasp, are improved by persistently denying the appetite and affording the body a continuous under-supply of nourishment, is a serious error, however much it has been endorsed by philosophers, theologians, and athletic trainers. Ethnology can trace the physical and mental decay of whole nations to a long course of insufficient food. The Bushmen of South Africa have already been quoted as an example of the most stunted and inferior representatives of the human race ; but let it be added that this is true only of those who have for generations lived in a condition of semi-starvation in the unproductive wilds of the Kalahari Desert ; while others of the same stock, whom Livingstone met in the fertile districts south of the Ngami Lake, were quite up to the average stature, finely proportioned, and nowise deficient in intelligence. The Australians in the well-stocked hunting-grounds in the east of that continent are a type very superior to the wretched speci mens who eke out a half-famished existence in the inhospitable bush of the west coast. The miserable Fuegians, who are described by Darwin as on the lowest plane of the species, deriving a precarious subsistence by picking up the shellfish and seaweeds of their rocky shores, are a branch of the same parent tree which in the rich forest-lands of Chili produced the bold Araucanians, who for centuries have held their own against the encroachments of the white man, and won his respect by their martial prowess and mental aptitude.
Similar examples are common throughout history and all over the world. They teach that it is not the quality of food—provided that it contains the elements of nutrition—nor yet the monotony or diversity of diet, but almost exclusively its quantity, that exerts an influence on the abilities and historic importance of a nation when studied simply as a question in physiology.
Sources of the Food-SzWly. —But the food-supply has other very important bearings besides the merely physiological one. Nothing has more visibly influenced the progress of culture than the various methods resorted to for procuring, preserving, and preparing food ; and to these points, therefore, we must devote careful consideration in reflecting on the principles of Ethnology.
All communities obtain their food either (r) from natural products, (2) from cultivated products, or (3) by exchange and commerce, or by a com bination of these methods. In proportion as one or the other prevails or becomes the sole method, all the other characteristics of the community become altered to correspond to this primal condition of existence. We will examine each of them separately.