Obstacles to habits of health are numerous; therefore the importance of correcting those habits of factory, family, trade, city, or nation that make health habits impracticable. We must change others' prejudices before we can breathe clean air on street cars without riding outside. When one's co-workers are afraid of fresh air, ventilation of shop, store, and office is impossible. So long as parents fear night air, children cannot follow advice to sleep with windows open. Unless the family cooeperates in making definite plans for the use of toilet and bath for each member, constipation and bad circulation are sure to result. Indigestion is inevitable if employees are not given lunch periods and closing hours that permit of regular, unhurried meals. Cleanliness of person costs more than it seems to be worth where cities fail either to compel bath tubs in rented apartments or to erect public baths. A temperate subsistence on adulterated, poisonous, or drugged foods might be better for one's health than gormandizing on pure foods. No recipe has ever been found for bringing up a healthy baby on unclean, infected milk; for avoiding tuberculosis among people who are compelled to work with careless consumptives in unclean air; or for making a five-story leap as safe as a fire escape. Perfect habits of health on the part of an individual will not protect him against enervation or infection resulting from inefficient enforcement of sanitary codes by city, county, state, and national authorities. [Illustration: AT JUNIOR SEA BREEZE, TEACHING MOTHERS THE HEALTH ROUTINE FOR BABIES] The "municipalization" or "public subsidy" of health habits is indispensable to protecting industrial efficiency. Public lavatories, above or below ground, have done much to reduce inefficiency due to alcoholism, constipation of the bowels, and congestion of the kidneys. Theaters, churches, and assembly rooms could be built so as to drill audiences in habits of health instead of fixing habits of uncleanly breathing. Street flushing, drinking fountains, parks and breathing spaces, playgrounds and outdoor gymnasiums, milk, food, and drug inspection, tenement, factory, and shop supervision, enforcement of anti-spitting penalties, restriction of hours of labor, prohibition of child labor,--these inculcate community habits of health that promote community efficiency. It is the duty of health boards to compel all citizens under their jurisdiction to cultivate habits of health and to punish all who persistently refuse to acquire these habits, so far as the evils of neglect become apparent to health authorities. The unlimited educational opportunity of health boards consists in their privilege to point out repeatedly and cumulatively the industrial and community benefits that result from habits of health, and the industrial and community losses that result from habits of unhealthy living. FOOTNOTES: