Perspiration, benefits of, 76. Philosophy, help to be obtained from, in field of mental hygiene, 114; Oriental superior to Occidental in training in control of attention, 115-116. Physical examinations, a remedy for degenerative tendencies, 292. Physiological effects of alcohol, 236-244. Pickles, table of food values of, 182. Pie, food value of, 29, 179. Pillows, use of, in sleeping, 104. Plague, spread by fleas and lice, 74-75. Play, the halfway stage between work and rest, 100-101. _See_ Work and play. Playgrounds, outdoor, 19. Plays, hygienic value of, as recreation, 99. Pneumonia, outdoor treatment for, 21; trend of death rate from, 285. Poisons, from constipation, 51-56; relation of posture to, 57-64; habit-forming drugs and patent medicines, 65; substitution of milder for the more injurious, 65-66; alcohol, 67-68, 227-249; tobacco, 68-69, 250-271; infections with germs, 69-78; teeth and gums as a source of infection, 78-81; focal infection and autointoxication, 81-83. Poor, disadvantages of the, in opportunities to live a healthy life, 128. Posture, physical value of an erect, 57; breathing exercises for correcting evils of, 58; in standing and walking, 58-59; of the feet, 59-60; in sitting, 60-62; pains due to faulty, 62; effects of faulty, in children, 62; teaching of correct, 63; relation to character, 63-64; corrective exercises for faulty, 221-223; in cases of flat foot, 223. Potatoes, food value of, 29, 176; valuable because of alkalinity, 43; among the best foods, 48; a cheap source of starch and sugar, 131; for underweight, 220. Preservatives, harmful, 65. Preventability of disease and death, 135-136. Preventive dental treatment, 86-87. Preventive medicine, practise of, 2-3; application of methods by people themselves, 3. Program, constructing a day's, 120; main features of a eugenic, 167. Prostitutes, disease among, 77. Prostitution. _See_ Social evil. Protein, function of, as a constituent of food, 35-36; examples of, 36; question of right proportion of, 36-37; common error of diet in using too much, 38; injuries from overabundance of, 38-39; poisoning caused by decomposition of, in the colon, 56; in cheap foods, 131; list of foods high, moderate and deficient in, 171; experiments to determine value of, in diet, 197-199. Prunes, food value of, 30, 179; laxative quality of, 52. Prussia, mortality statistics of, 286, 290-291. Public hygiene, 157; what is included under, 157-158; progress made in, 158; various important measures of, 161-163. Puddings, table of food values of, 179. Pumpkins, cellulose in, 41. Purins, in flesh food, leading to production of uric acid, 39; found in some vegetable foods, 40. Pyorrhea, action of, 79-80; treatment for, 85-86.