Pain, Relations of, to pleasure, 181 Sensation of, 180 Uses of, 180 Pancreatic juice, 95 Uses of, 95 Pancreatin, 95 Paraplegia, 163 Parlor gymnasium, 36 Passages, Air, 125 Pelvis, 19 Pepsin, 92 Peristaltic action of the stomach, 92 Peritoneum, 94 Perspiration, Daily amount of, 46 Sensible and insensible, 46 Uses of, 46, 145 Perspiratory glands, 45 Physical strength, 29 Culture, 33 Physiology, 11 Animal, 11 Comparative, 11 Human, 11 Vegetable, 11 Pia mater, 152 Plasma of the blood, 102 Pleura, 124 Pleurisy, 128 Pneumo gastric nerve, 171 Pneumonia, 128 Poisons and their antidotes, 247 Potash in the blood, 57 Potato, 73 Presbyopia, 215 Preservation of the teeth, 85 Ptyalin, 88 Pulsation of the heart, 113 of the arteries, 116 Pulse, 115 Form of the, 116 Writer, 116 Pylorus, 90 R. Radial artery, 116 Red corpuscles of the blood, 102 Reflex action of the spinal cord, 165 Requisites for, 167 Uses of, 167, 170 Causing convulsions, 169 Objects of, 170 of the brain, 174, 175 Rennet, 58 Respiration, 123 Change of blood in, 123-133 Frequency of, 129 Movements of, 128 Object of, 123 Organs of, 123 Respiratory labor, 135 Rest, necessity for, 38 Retina, 206 Retinal light, 207 Ribs, Movements of, in respiration, 128 S.