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 excretion of nitrogen. When the body became used to it, this decreased, but the proteid excreted by the kidneys contained an abnormal amount of a harmful material called uric acid. Uric acid, a substance which is present in rheumatism and other diseases, is usually destroyed by the liver. As the burden of destroying the alcohol falls chiefly upon the liver, it is not surprising to find that it is so weakened and injured by alcoholic drink that it cannot fully perform its important functions. Bright's disease and other diseases accompanied by uric acid are more frequent among persons who use alcoholic drinks.

Definition of Food.—A food is anything which, after being absorbed by the body, nourishes the body without injuring it. Does alcohol or tobacco come within this definition?

Advantages of Good Cooking.—Taste and flavor may be developed; parasites are killed; taste may be improved by combining foods; starch grains are burst and the food softened. Thus digestion is aided.

Disadvantages of Bad Cooking.—Proteid foods are hardened; flavors may be driven off; too many kinds of food may be mixed; cooked vegetables are more likely to ferment than raw vegetables; palatable food may be made tasteless or soggy or greasy; soda and other indigestible ingredients may be added; food may be so highly seasoned as to cause catarrh of the stomach; it may so stimulate the appetite that so much is eaten as to overload the stomach. Food may be made so soft that it cannot be chewed and is eaten too rapidly; for instance, bread shortened with much grease.

The Five Modes of Cooking.—Food may be cooked (1) by heat radiating from glowing coals or a flame, as in broiling; (2) by hot air, as baking in a hot oven; (3) by boiling in hot water or grease, as frying; (4) by hot water, not boiling, as in stewing; (5) by steaming.

Radiant Heat.—Toasting bread and broiling meat are examples. The meat should be turned over every ten seconds to send its juices back and forth, thus preventing their escape, and broiling the meat in the heat of its own juices. Roasting is an example of this method combined with the second method. The fire should be hot at first in order to sear the outside of the meat and prevent the escape of its juices. If the piece roasted is small, the hot fire may be kept up; but if it is large, a longer time is required, and the fire should be decreased, otherwise the outside will be scorched before the central part