Certain it is that advertising is an art promoted by the severest competition of the cleverest brains. It is a force which we cannot afford to ignore. If we can harness it to the promotion of aids to health, it will do more good than all the hygiene books ever written. To this end we must educate ourselves to distinguish between goods which do what they profess to do and those which do not. A good eye opener would be to keep for a week clippings from a high-priced daily paper, a penny daily paper, and one or two representative magazines, including a religious paper. Teachers and parents can very easily interest children in such clippings. Moreover, they can use the bulletin method, the stereopticon exhibit, the _cumulative illustration_ of a fact, which is the essence of successful advertising. Boards of health can use all the typographical aids to clear understanding,--cuts, diagrams, interesting anecdotes. In New York both the health board and the school board have issued circulars and given illustrated lectures, some of them being in school and some on public squares. Medical and sanitary societies and other educators can be induced to follow what a successful business man has called the three cardinal rules of advertising: First, put your advertisement where it will be seen. (Tell your story where it will be heard.) Second, write it so that people will read it. (Tell it so that people will understand it.) Third, tell the truth, so that people will believe it. CHAPTER XXXIX IS CLASS INSTRUCTION IN SEX HYGIENE PRACTICABLE? Among remedies for preventable disease and preventable poverty, the following was urged at a national conference for the betterment of social conditions: "We have been too prudish. Because we have been unwilling to teach school children the evils of violating sex hygiene, we have been unsuccessful in combating evils justly attributable to ignorance on the part of girls as to the duties and dangers of motherhood." This point of view is shared by so many men and women that a national body was organized in 1905 to promote the teaching of sex hygiene,--the Society for Sanitary and Moral Prophylaxis. This society has its headquarters in New York, and distributes at cost lectures and essays. The second of its educational pamphlets is addressed to teachers, and is entitled "Instruction in the Physiology and Hygiene of Sex." The introduction asks eleven questions of the teachers as follows: 1. Do you wish a pamphlet on sex subjects to hand to your pupils? Why? 2. Do you wish separate pamphlets for boys and girls? 3. For what age limits and social conditions do you wish them? 4. What topics do you wish the pamphlets for boys to "handle"? 5. What topic do you wish the pamphlet for girls to "handle"? 6. If you think one pamphlet sufficient for both sexes, what should it consider? 7. How far do you go in teaching sexual hygiene or reproduction? By what method?