—Discharges from the bowels and bladder contain various germs, and constitute one of the most important routes by which germs of typhoid fever, cholera and certain other diseases
travel from person to person. Keeping sewage out of the water supply is consequently of great importance. Where a system of sewage disposal exists, the responsibility of making the system adequate and thus safeguarding public health rests upon the community as a whole. Communities ordinarily get just as much, or just as little typhoid fever as they are willing to endure.
Fig. 9.—How a well may be polluted. (From "The Human Mechanism." Copyright by Theodore Hough and William T. Sedgwick. Ginn and Company, publishers. Used by permission.)
In places having no system of drainage privies must be used. They can be made harmless, as army camps prove, but they require scrupulous
care. Fecal matter must be prevented from draining into wells and other water supplies, and must be screened from flies. The privy should be located at a distance from the well. The minimum distance that is safe depends in each case upon the nature of the soil and the direction of the natural drainage. Even when the privy is situated below the well on sloping ground, drainage may still occur from the privy to the well; however, a well-made, properly located pit privy is safe unless it is near a limestone formation. The dry earth system is satisfactory in places having an efficient public scavenger system; in this system pails or cans are used to receive the discharges, which are then covered with sand, ashes, earth or, preferably, chloride of lime. The buckets are frequently emptied and the contents buried at least one foot below the surface of the ground. The objection to this method for more extended use is that proper care of the cans is a disagreeable duty of which most households soon tire.
Personal Cleanliness.
—The main functions of the skin are three: to protect underlying tissues, to excrete waste matter, and to regulate bodily heat by checking or allowing the evaporation of perspiration. After perspiration has evaporated solid matter is left upon the skin, and oily matter also is deposited on it by the glands that keep the
skin lubricated. Removing these and other materials at least once a day is desirable to improve the bodily tone and sense of well-being. Real cleanliness is impossible without frequent use of warm water and soap.
Cold baths are stimulating, though not very efficacious for cleansing purposes. They are valuable tonics if properly used, but delicate or elderly persons should use them only by a physician's advice. Chilly feelings or depression following should be the signal for any person to discontinue cold bathing or swimming in cold water.