CLIMATE.

The inhabitants of cold climates require those articles of food which produce the largest amount of animal heat, such as oil, tallow and fat meats, which contain from sixty-six to eighty per cent. of carbon. The natives of the arctic regions consume enormous quantities of fat and oil, and seem to relish them as great luxuries; the inhabitants of tropical regions subsist mainly on rice, fruits, vegetables and lean meats. It would be impossible to live in Greenland on the plaintain and rice of the Hindoo, or in Hindostan on the seal fat and whale oil of the Greenlander.

In temperate climates we require different kinds of food at different seasons of the year. In winter we consume larger quantities of fat meat and carbonaceous food, and in summer more fruit and vegetables. Were we to indulge in the summer in the same diet which we might find highly conducive to health in the winter, the system would soon become burdened with an excess of carbonaceous matter, and induce congestion and inflammatory diseases. It is therefore highly important that each person should possess some knowledge of the properties of different articles of diet, and select from time to time those which he may think most suitable to his own organization.

Different substances are nutritious in proportion as they yield, when digested, those elements which are found to exist in the different tissues of the body. Animals do not possess the power of forming new elements, or of converting one element into another, and it necessarily follows that the elements of their growth and nutrition must be derived from the food which they take.

The largest part of nearly all the substances which make up the human body are composed of oxygen, hydrogen, nitrogen and carbon, and different substances are regarded as nutritious in proportion as they furnish these essential elements of our organization. In general, those substances may be regarded as the most important articles of diet which furnish, with the greatest facility of digestion, the largest amount of these elements.

Milk is regarded, perhaps correctly, as the plainest and simplest kind of food. Cow’s milk is composed of:

Casein,4.48
Butter,3.13
Sugar of milk,4.77
Various salts,.60
Water,87.00

Milk, being furnished by nature as the only food for the young of the mammalia during a certain period of their existence, contains all the elements necessary to the nutrition and the growth of the body. Out of the casein are formed the albumen and fibrin of the blood. The butter serves for the formation of fat, and contributes, with the sugar, to the support of animal heat, by yielding carbon and hydrogen to be burnt in the lungs. The earthy salts (phosphate of lime, etc.) are necessary for the development of the bones, the iron required for the blood, corpuscles and the hair.

In this country, meat constitutes an important part of the diet of almost every family. As a general rule, animal food is more easily digested, contains a greater amount of nutriment, and is more stimulating than any of the varieties of vegetable food.

As minuteness of division and tenderness of fibre facilitate digestion, young meats are more tender than old; thus, roasted pig is more speedily digested than broiled pork; steak and boiled lamb sooner than boiled mutton. Still, there are some exceptions to the digestibility of young meats, veal, and with some persons lamb, are slower of digestion than beef or mutton.

The vegetable kingdom greatly exceeds the animal in the number and variety of the aliments which it furnishes to man. It is well known that the four essential elements, carbon, oxygen, hydrogen and nitrogen, which form an important part of all animal compounds, are also to be found in great abundance in all vegetable compounds; it is owing to this fact that different animals are nourished equally well on an exclusive diet of either. The lion, tiger and other animals which live exclusively on animal food, give no evidence of being better nourished than the deer, the ox, and animals which subsist wholly on vegetable food; but the apparatus for digestion in each class is constructed with an evident adaptation to the kind of diet on which the different animals subsist.

In man the digestive apparatus is more extensive than in flesh-eating animals, but is less complicated than in those which are confined to vegetable food alone. Man is therefore omnivorous, both in his structure and in his habits.

But the universal tendency of mankind gives preference to a mixed diet. The most perfect development and the greatest individual vigor are to be found among those races in which a mixed diet is the prevalent habit.

During the warm season vegetables and fruits may be made the means of great mischief or of great good. Perfectly ripe fruits or vegetables are highly useful and well adapted to the wants of the system at that season of the year; yet they may become, and often are, a prolific source of disease. So frequently is this kind of food a cause of bowel complaint that city physicians discard it wholly from the diet of children not under their immediate supervision.

Vegetables and early fruits that have been long exposed, in a malarious or filthy market, or in transportation, are unquestionably dangerous articles of food for all persons. But the injurious consequences which follow the use of ripe and wholesome vegetables and fruit are, in almost all cases, the results of imprudence. They are either in an improper condition to be used as food, or the quantity is too great, or they are taken at improper hours.

In either case there is a great change in the usual diet. Instead of a lack of refrigerant food, there is now an excess of it. Active fermentation takes place in the process of digestion, and results in serious derangement in the alimentary canal, which leads to cholera morbus, diarrhœa or dysentery.

During warm weather vegetables and fruit are to be regarded as safe only when used as an accompaniment to other food; they are not adapted to meet all the wants of the system, and therefore should not constitute a full meal at any time. In the country, where this kind of food is enjoyed daily in a proper condition to be eaten, injurious consequences are quite rare, and then they are the result of an excess, or of an indulgence of an appetite at irregular hours.

Much care is also requisite to prevent imperfect mastication of this kind of food. Orange peel and the skins and stones of cherries, plums and grapes are wholly indigestible, and often cause serious mischief when swallowed. Cucumbers, green potatoes, green fruit of all kinds should be wholly discarded from the diet.