The most unhealthful kinds of food, are those, which are made so by bad cooking; such as sour and heavy bread, cakes, pie-crust, and other dishes consisting of fat, mixed and cooked with flour; also rancid butter, and high-seasoned food. The fewer mixtures there are in cooking, the more healthful is the food likely to be. There is one caution, as to the _mode_ of eating, which seems peculiarly needful to Americans. It is indispensable to good digestion, that food be well chewed and taken slowly. It needs to be thoroughly chewed, in order to prepare it for the action of the gastric juice, which, by the _peristaltic motion_, will be thus brought into universal contact with the minute portions. It has been found, that a solid lump of food requires much more time and labor of the stomach, than divided substances. It has also been found, that, as each bolus, or mouthful, enters the stomach, the latter closes, until the portion received has had some time to move around and combine with the gastric juice; and that the orifice of the stomach resists the entrance of any more, till this is accomplished. But, if the eater persists in swallowing fast, the stomach yields; the food is then poured in more rapidly than the organ can perform its duty of digestion; and evil results are sooner or later developed. This exhibits the folly of those hasty meals, so common to travellers, and to men of business, and shows why children should be taught to eat slowly. After taking a full meal, it is very important to health, that no great bodily or mental exertion be made, till the labor of the stomach is over. Intense mental effort draws the blood to the head, and muscular exertions draw it to the muscles; and in consequence of this, the stomach loses the supply which it requires when performing its office. When the blood is thus withdrawn, the adequate supply of gastric juice is not afforded, and indigestion is the result. The heaviness which follows a full meal, is the indication which Nature gives of the need of quiet. When the meal is moderate, a sufficient quantity of gastric juice is exuded in an hour, or an hour and a half; after which, labor of body and mind may safely be resumed. When undigested food remains in the stomach, and is at last thrown out into the bowels, it proves an irritating substance, producing an inflamed state in the lining of the stomach and other organs. The same effect is produced by alcoholic drinks. It is found, that the stomach has the power of gradually accommodating its digestive powers to the food it habitually receives. Thus, animals, which live on vegetables, can gradually become accustomed to animal food; and the reverse is equally true. Thus, too, the human stomach can eventually accomplish the digestion of some kinds of food, which, at first, were indigestible.