MILITARY SANITATION. Military sanitation is largely a matter of engineering combined with discipline. The health and fighting strength of a command is maintained by (1) excluding from the service the physi cally unfit and those predisposed to disease, by (2) the exercise of surgical and medical skill in promptly restoring the sick and wounded to duty, and (3) by securing preventive measures such as the various vaccinations, inoculations and prophylactic treatments tending to increase individual powers of resistance to disease or to prevent its development after infection. All of these are the special province of the Medi cal Corps.
The engineering problems connected with camp sanitation comprise water supply, drain age, disposal of refuse (animal wastes, garbage and rubbish) and the selection and laying out of camp sites, or castramentation. Nearly all diseases to which the soldier is subject are caused by germs, which are either little animals or plants so very small that they can only be seen by aid of the microscope. All diseases caused by germs are ((catching."' All other dis eases are not "catching." There are only five ways of catching diseases: (a) Getting certain germs on the body by touching some one or something which has them on it. Thus, one may catch venereal diseases, smallpox, measles, scarlet fever, chicken pox, mumps, boils, body lice, ringworm, barber's itch and other dis eases. Wounds are infected in this manner. (h) Breathing in certain germs which float in the air. In this way one may catch pneumonia, consumption, influenza, diphtheria, whooping cough, tonsilitis, spinal meningitis, measles and certain other diseases. (c) Taking certain germs in through the mouth in eating or drink ing. Dysentery, cholera, typhoid fever, etc., may be caught in this manner. (d) Having certain germs injected into the body by the bites of insects, such as mosquitoes, fleas and bedbugs. Malaria, yellow fever, dengue fever and bubonic plague may be caught in this way. (e) Inheriting the germ from one's parents.
In both permanent and temporary camps the water supply is a matter of the greatest im portance both as to quality and quantity. Where the character of drinking water is the least in doubt it should be made safe by sterili zation. The usual method of boiling cannot
always be resorted to, owing to lack of time and fuel, and troops in the field generally re sort to the chlorination method of sterilization which simplifies the problem. The liquid chlorine treatment, though probably the most efficient, is not adapted to military field use on account of the apparatus required. Of the hypochlorites, that of sodium, in liquid form, is more efficient for its bulk, but that of cal cium (bleaching powder) is ordinarily the more readily obtainable. The latter, however, when loose or packed in cardboard, loses its strength very rapidly. It is best kept by mak ing up and bottling a strong stock solution.
The strength used in sterilizing municipal supplies is 0.2 parts per million, that in the field about 10 times as great, or 2.0 per million. In the former case fresh powder, from air-tight drums, is usually available, the mixing is more thorough and the distribution more carefully regulated. Usually also the water has been partially purified by sedimentation in a reser voir. In such cases, 20 minutes is supposed to render the water safe for drinking. For field use, a level teaspoonful of calcium hypochlorite (chloride of lime) is dissolved in two quarts of water for a stock solution. One teaspoonful of this solution is added to a gallon of water, or 10 tablespoonfuls to a barrel. The water is considered safe to use after standing for 30 minutes.
A sterilizing hag, of linen fabric, holding about 40 gallons of water, is issued to troops in the field. As the chemical acts better in clear water, a filter cloth is provided to strain it in filling the bag. The sterilizing medium is calcium hypochlorite, sealed in glass tubes, which are marked with a file to facilitate breaking them without fragments. They each contain about 15 grains of the chemical, which gives a proportion of 2.0 parts per million, sufficient to destroy germ life in even highly in fected, though not in sewage polluted, waters. The bag is covered to keep out dust, and the water is cooled by the evaporation of the mois ture which exudes through the fabric. Water is drawn off through small self-closing faucets set in a circle around the bag, slightly above the bottom.