b. =The Tonic Bath.=--In warm weather when one takes a daily bath to insure cleanliness, at least five of these baths each week may be in cold water, sufficiently cold to secure the tonic effect as described above. In cold weather, when one takes not more than one or two warm soap baths a week, the cold tonic bath can be made to serve a most important purpose in the hygiene. Some have followed the custom of immersing the body completely in a tub of cold water. This method of taking the cold bath is not to be recommended except for those who are in the most robust health, and in these cases, so vigorous a treatment is not necessary nor particularly beneficial. The author has seen many people who were injured by this method of taking the tonic bath. There are two methods to be recommended: Those who have access to a cold shower may stand for a moment, and for a moment only, under the cold shower, then step at once upon a warm rug and rub the whole surface of the body vigorously with a dry crash towel until the whole surface of the body glows with the warmth of the reaction. If one does not have access to the cold shower, he may take a most effective tonic bath in his room, using cold water, the coldest obtainable, and a bath sponge, or even a wash cloth, dipping the sponge into the cold water, then pressing out enough of the water so that there will be no excess of water to run over the surface of the body from the sponge. Begin by sponging face, neck, shoulders, arms and chest, then wipe these parts dry, subject them to vigorous friction with the crash towel until the arms, shoulders and chest particularly glow with the warmth of the reaction. While the upper half of the body is receiving its bath the lower half may be kept covered, and conversely. This tonic bath should be taken immediately upon arising in the morning, and as a part of the morning toilet. If one takes such a tonic bath on arising, then dresses hurriedly and takes a brisk walk of fifteen or thirty minutes, the regime quickly brings his body into the most vigorous and robust state of health; unless there is something wrong with his digestion or his excretion, and even moderate derangements of these will be very likely to be corrected by the regime just suggested. 3. EXERCISE. Incident to the above topic mention has been made of the brisk morning walk before breakfast. This has a most salutary tonic effect besides the influence that it exerts upon the bowel movements. Not the least important result of this morning exercise depends on the fact that the lungs are repeatedly and completely inflated with the pure out-of-door air. This naturally exerts a most valuable influence upon the development of the lungs in the youth or the maintenance of their vigor in middle age.