_Ingrowing Toe-nails._—The common causes of ingrowing toe-nails are improper foot-wear and an improper method of cutting the nails. If the nail is cut too short, especially at the angles, while at the same time the shoe is too short or too narrow, the skin of the toe is forced over the nail, so that it necessarily happens that, by the further growth of the nail, the flesh of the toe is pushed still further over, until a point is reached where inflammation is set up. There is excruciating pain, which may be accompanied by the formation of a small tumor, which forms pus and may go on to granulation—the so-called “proud flesh.” The preventive measures of the trouble are, first, in cutting of the nails. The toe-nail should be cut in a concave form, the outer angle projecting beyond the toe. If there is a tendency for the flesh to grow over the nail, the flesh should be pushed back from the nail, and fastened in this position with a strip of oxid of zinc plaster, and a gauze packing should be inserted under the nail-edge. A saturated solution of boric acid serves as an antiseptic dressing. It is often possible to cut off the projecting nail, and, by the use of the boric acid dressing, the trouble disappears in a few days. Attention should always be given to the toe-nails when bathing. _Corns._—There are two varieties of corns; both are very painful. Soft corns come between the toes, and unless absorbent cotton is inserted to prevent the rubbing of the toes together, a second corn appears on the opposing surface of the adjoining toe. A very effective remedy for this is the application of blue-stone, or sulphate of copper, to the corn. The stone is moistened in water and then applied thoroughly to the corn; absorbent cotton should be placed between the toes. In very severe cases it may be necessary to stay off the feet for a few days and keep the foot upon a chair. Hard corns must be cut down with the greatest care. It should be done directly after the bath, so as to have the skin in as nearly an aseptic condition as possible. A small scalpel, composed entirely of steel, should be kept for this purpose. It must be thoroughly cleaned after it is used, and just before its use be sterilized by boiling for five minutes. The reasons for these precautions are the possibility of cutting into the flesh and setting up blood-poisoning by the entrance of germs into the wound. CHAPTER IV THE DIGESTIVE SYSTEM: GENERAL PRINCIPLES IN HUMAN NUTRITION AND DIETETICS The Digestive Tract; Care of the Mouth and Teeth; Controlling Factors of Digestion; Psychic Aspect of Digestion; Importance of Mechanical Factors; Chemical Changes of Food in the Stomach; Intestinal Digestion; Metabolism; Constipation and its Treatment.