No matter how thoroughly an individual attempts to care for his own health, he will find it almost impossible to avoid infections, at times, without the organized help of the community in which he lives. A man may do his best to keep his windows open, to breathe deeply, to eat hygienically, to hold his activities within the limits of overfatigue, to screen his house against flies and leave no tin cans about his kitchen door to breed mosquitoes; but if the city in which he lives has no good air for him to breathe, if his city's water supply is contaminated, if neighboring malarial swamps are not drained or covered with oil, if flies alight on the food before it comes to his own house, if the food contains disease germs or dangerous preservatives, or if his next-door neighbor visits him and leaves infection behind him, mere personal defenses will hardly be adequate. Even in so private a matter as moving the bowels, sometimes the fault lies partly with circumstances beyond the control of the individual. Unfortunately in most of our cities and small towns "Comfort Stations" are rare or unknown, and when they are available they are often in such an insanitary condition as to be a source of danger through the spread of communicable disease. Constipation, as we have seen, is a far more serious matter than it is sometimes thought to be. It is therefore incumbent on the individual to contribute his share to the hygienic work of society as a whole, in particular to take an active interest in health legislation and administration. A man can not live to the best advantage in a life isolated from all social obligations, any more than could Robinson Crusoe, who was unable to launch his canoe in the ocean, after he had been at great pains to construct it, because he had no one to help him. Each man should take part in the great social hygienic struggle, if he is to reap the highest rewards in his own personal hygienic struggle. And he can do a great deal if he will be patient and persistent. If, for instance, he would always insist on suitable air conditions in public buildings, electric cars, theaters, and churches, and encourage others to do so, it would not take long to make air reform general. [Sidenote: The Consumer's Duty] In fact, it is the common public, constituting the consumer, who has it in his power to bring about most of the necessary reforms in public hygiene. When the consumer really values hygienic environment, the producer will supply it. The great improvement in recent years in drinking water was brought about through the appreciation, by the consumer, of the danger from impure water. His complaints produced the change. Hotels found it profitable to provide and advertise pure water. So also the education of the public as to the dangers of a common public drinking cup led to the invention of bubbling fountains and cheap individual cups and to the introduction of these conveniences in railway stations and other public places.