Sleep, one of the two great forms of inactivity, 89; means of inducing, 102-103; importance of, to health, 103; hours of, 103; eating before, 103-104; use of pillows, 104; type of bed, 104; effect of mental attitude on, 104-105. Sleeping, out-of-door, 3, 20-24, 104; a preventive of colds, 9, 276; for underweight, 220. Sleeping porches, arrangement of, 22-23. Sleeping tents, 23-24. Social evil, remote causes of, 123; cooperation needed in movement against, 163. Soups, food values of, 183. Sour milk, among the best foods, 48; a means of reducing decomposition of protein in the colon, 56. Specialists, medical, "one idea" doctrines of, 122. Spinach, cellulose in, 41. Spinal curvature, sometimes caused by faulty posture, 62. Sponge-cake, food value of, 29, 179. Squash, cellulose in, 41. Standing, correct posture in, 58-59. Starch, cheap sources of, 131. Sterilization of defectives, 323. Stevenson, R. L., on duty of being happy, 115. Sugar, food value of, 30, 182; danger from overuse of, 48; cheap sources of, 131; taking of, for underweight, 220. Sunlight, benefits of, to air, 14. Sweden, American ideals of perfect manhood and womanhood inferior to those of, 4; attention to individual hygiene in, and decline in death rate, 159; mortality statistics of, 286, 292. Sweetbreads, excess of acids produced by, 39; among the worst foods, 48. Sweets, table of food values of, 182; time for taking, 220. Swimming, as exercise, 94; an example of healthful activity and relaxation, 101-102; for overweight, 217. Syphilis, destructive effect of, 78; resistance to, weakened by alcohol, 240. Systemic injuries from mouth infection, 80-81. Table, posture in sitting at a, 61. Tea, degree of injury from, 66. Teeth, benefits to, from hard foods, 41; evils of insufficient mastication, 44; infection from decayed, 78-83; danger from over-dentistried, 83; method of cleansing, 84-85; periodic examinations and cleanings, 86-87; question of saving, at expense of other parts of body, 87; correction of irregularities, 87-88; care of temporary, 88; results of teeth hygiene, 88; malformation of, a cause of nasal obstruction and colds, 272. Temperature of living-rooms and work-rooms, 11. Tents for outdoor sleeping, 23-24. Thinking, exercise in, 97. Thoughts, effect of character of, on sleep, 104-105. Ticks, diseases spread by, 74. Time, taking of, for hygienic living, 132-133. Tobacco, injury from poison in, 65; ill effects of, 68-69; derivation of, 250-251; composition of, 251-255; effects on animals and on man, 255-265; increase in use of, 267-268; references concerning, 268-271. Tobacco heart, risks accompanying, 263. Tobacco smoke, air vitiation from, 13; amount of nicotin in, 254-255, 260-261.