Sleep is a necessary part of good hygiene. It promotes health and prevents disease. It is largely in sleep that the system renews itself, that growth takes place, that waste products are thrown off, and the body repairs its wastes. No less than eight hours for grown persons and ten for children should be employed in sleep. Late hours and sleepless nights are the frequent cause of nervousness, eye strain, nervous prostration, and the beginning of brain troubles and insanity. Bathing is also necessary to good health. The pores of the skin play a large part in carrying off the wastes of the body, through the perspiration, and if these become clogged, this poisonous material remains in the system. We have all noticed how a bath refreshes and gives tone to the entire body by opening the pores. The skin is composed of minute scales, arranged in layers like fish scales. The tiny crevices between these form a lodging place for dirt and germs. If these remain, our own bodies are constantly exposed to their infection, if they drop off, as some are constantly doing, we may spread the contagion to others. This is strikingly illustrated by scarlet fever, smallpox, and similar diseases where these minute scales are the sole source of contagion. Exercise is another necessity of health. Regular physical culture in a gymnasium will develop any muscle or part of the body almost at will, but if this be not possible much can be accomplished in developing the body by simple work. Gladstone found health in chopping wood, Roosevelt in a daily tennis game, and President Taft in golf. Many find it in gardening or farming. These all help to develop vigorous bodies. Anything which brings into moderate play any set of muscles, which increases the circulation, or stimulates the secretion is beneficial. House-work, which, in its various forms, brings into use all the muscles of the body, is a wholesome exercise for women. Those who do no house-work seldom substitute for it any other active exercise, and many diseases which are caused by deposits of waste tissues that are not thrown off by the body, are the result. Rest--recreation--pleasure--these are as necessary to health as anything else, but the American people are slow to learn the need of them. We hear much of nervous prostration as an American disease. It is due to a variety of causes,--high living, late hours, ill-ventilated rooms, and climate; but chief of all the causes is the long hours of work under strong pressure. Work done in a hurry and without rest may accomplish many things, but it invariably causes a corresponding loss of nerve force. Fatigue, by checking bodily resistance, gives rise to all kinds of poisons in the system. Every part of the body feels the ill effect of continued exhaustion.