Perspiration, secretion of, during sleep, 9 Pettenkofer, experiments of, on oxidation in the tissues, 9 experiments of, on respiration in sleep, 6 Pettenkofer and Voit, on tissue changes, 10 Pflüger, hypothesis of, regarding the cause of sleep, 21 Phosphatic diathesis, a cause of insomnia, 72 Phosphoric acid, 72 Phosphorus, 71 Phthisis, cough of, relieved with lactucarium, 88 insomnia of, relieved with paraldehyde, 80 treatment of, with opiates, 87 Physiological activity, reduction of, during sleep, 5 Physiological cause of somnambulism, 180 Planchette-writing, 228 Pleuritic pain, 99 Pneumogastric nerves, insomnia caused by affections of, 51 Pneumonia, 68, 100 Porter, effects of, 76 Potassium bromide, 88 Preyer, his theory of sleep, 20 Psychical Research, Society for, investigations by, 149, 217 Pulse, state of, during sleep, 6 Punkah, use of, to promote sleep, 44 Quetelet, observations of, on respiration during sleep, 5 Quinine and opium, use of, in fever, 104 Reasoning powers, arrest of, during sleep, 3 Recollection of the events of artificial somnambulism, 227 of the events of natural somnambulism, 188 Reflex movements during sleep, 12 Refrigeration, threefold effect of, 49 Relation between molecular movement and the generation of ideas, 24 Respiration during sleep, 5 Revelation through dreams, 160 Revery, nature of, 120 Rheumatic diathesis, a cause of insomnia, 72 Rosenthal, observations of, regarding lethargy, 33, 34 observations regarding apparent death, 35 Rush, Dr., observations of, on the revival of memory in dissolution, 165 Sailors, sleeping during a bombardment, 1 Sailor-boy, sleeping on a mast, 1 Salicylic acid, treatment of rheumatism with, 106 Saliva, secretion of, during sleep, 8 Samuel the prophet, dream of, 129 Sandwich Islands, climate of, for relief of insomnia, 114 Scarlet fever, treatment of, with baths, 74, 75 Scharling, observations of, regarding bodily temperature during sleep, 7 experiments of, on oxidation in the tissues, 9 Screaming fits of children, 112 Secretion, state of, during sleep, 8 Sedatives, nervous, 59, 73 Self-hypnotism, 219 Sensory excitement, effect of, upon the cerebral circulation, 27, 28 Sensory organs, condition of, during somnambulism, 191 Sexual organs, irritability of, 90 Shampooing, 61 Simon, P. Max, case of somnambulism related by, 182 dream related by, 142