Sex organs of boys, two functions of, 206 SEX, other purposes of, 305; life, principles of, 415; a resident part of life, 422; female organs of, 132 SEXES, similar in change of, 528; creative periods in, 532 Sex and social nature of girls, 158 Sex problems explained, 538 SEX ENERGY changes boy into man, 190; example--two full brother colts, 191; example--two full blooded chickens, 192; ways of using, 208; example--unsexed male horse, 218; caponized male bird, 219; eunuch, 219; unsexed girl, 219; for you to decide how used, 223 SEX HYGIENE, school instruction in, 560; silence a failure, 561; parents as instructors, 561; school can teach laws, 563 SEX IGNORANCE, parents not responsible for, 71; man as guilty as woman, 474 SEX INSTRUCTIONS, how a father failed in, 70; how a teacher failed in, 70; results of old method, 74; how a child gets information, 74; result of faults, 75; how to introduce, 84; how this can be done in schools, 86; author’s experience, 87; boy of ten, 123; girl of ten, 124; advantage of beginning early, 124; female form, 125; review of, 131; for boy, how to proceed, 169 Sex knowledge, views of past, 218 Sex life, relation of reading to disposition of, 229 Sexology, newly married should understand, 466 SEXUAL desire begins to wane, 543; discharge condition of, in unwell man, 190 SEXUAL GLANDS, two functions of, 220; the continuous function of, 220 Sexual necessity, unanswerable argument against, 315 Sex life, nature of, 304 Sexuality and sensuality, 463 SEXUAL ORGANS, 185; can be abused, 146; why given, 182; are not sinful, 182 Sexual system, names are pure, 183 SEX TRUTHS, two qualifications necessary to teach, 68; instruction of children in past, 71; desired by boys and girls, 77; how shall a child be told, 81; when shall a child be told, 82; the ideal way to tell, 84; teaching in public schools, 85 Sin, motherhood may not expose, 246 Skin, functions of, 371 Sleep, 289 Social and sex nature, relation of, 331 Social danger, 469 SOCIAL EVIL, two colossal blunders, 600; commercialization of, 603; why men are as guilty as women, 609 Social nature of young men, 331 Sowing wild oats, 431 Spitzka’s view of imbeciles, 477 Stricture, 324 Syphilis, 327; three stages of 327; innocent may be effected, 328; examples, 328-329 T Teacher, how he failed in sex instruction, 70 TEMPERAMENTS, 439; motive, 439; nervous, 440; vital, 440; like should not marry like, 440; law of complements, 441 Testes, inflammation of, 325 TOBACCO, use of, 177; habit and enormous evil, 53; smoking by Dr. Pidduck, 490; effects of, 490; users, children of, 490; where both parents use it, 491; and degeneracy, 491 Training of perfect plant or animal, 173 Troubles in family, how solved, 22 Truest bravery, 213 TRUE KNIGHT, 211; has one standard of morals, 215 Twins, 417 Twin brothers, 419 U