Heraclitus, 111. Hibernating animals, 77. Hippocrates, on respiration, 15, 20; on spirits, 20; works of, 15. Hofmann, Caspar, 5. Intellectual faculty, 105. Intellectual soul, 105. Lacteals, discovery of, 10. Laurentius, 29. Life, Aristotle on, 104; in blood, 76. Ligature, 42. Liver as source of veins and blood, 56, 60. Male, function of, 145. Milton, 70, 124, 155. Mitral valve, 58. Moderns, Harvey on, 2. Motor faculty, 105. Motor soul, 105. Muscle, function of, 84; function of, unknown to Aristotle, 53, 84. Natural spirits, 25, 27. Nerve impulse, 26, 32. Nervous system and spirits, 31. Net-like plexus, 22, 24. Nutritive faculty, 104. Nutritive soul, 50, 105, 145. Oxyhæmoglobin, 26. Paracelsus, 118. Pascal, Blaise, 96. Philosophers _versus_ physicians, 55, 60, 65. Physicians _versus_ philosophers, 55, 60, 65. Planets, 122. Plato, 23, 51, 112. _Pneuma_, 20, 23, 127, 147, 148. See also Spirits. Pores of septum, 27, 57. Porosities of tissues, 98, 100. Portal vein, 8. Powers of the elements, 130. Primitive moisture, 131. _Psyche_, 23, 104, 147. Psychical spirits, 23. Pulmonary circulation, 27, 38, 58, 101. Pulse, as caused by heat, 81; as dependent on heart, 83. Quintessence, 124. Respiration, and air, 15, 23, 31, 40; Aristotle on, 15, 30; and circulation, 11; Galen on, 16, 22, 27; Harvey on, 12, 18, 26, 28, 31, 39; Hippocrates on, 15, 20; and innate heat, 14, 15, 16, 18, 33, 39. _Rete mirabile_, 24. Scaliger, Julius Cæsar, 118; on innate heat, 117. Semen, Aristotle's view, of, 120, 128; heat in, 119, 124, 128, 140, 143; spirits in, 119, 128, 140, 148. Semilunar valves, 15, 16, 55, 62. Sensory faculty, 105. Sensory soul, 51, 105, 145. Sexes, Aristotle on, 145. Socrates, 112. Soul, in air, 147; Aristotle on, 51, 104, 114; in the blood, 103, 105, 156; as cause of vital activity, 143; and fire, 143; Harvey's view of, 103, 106; in the heart, 51, 114; intellectual, 105; motor, 105; nutritive, 50, 105, 145; sensory, 51, 105, 145. Spirits, 20, 23, 127, 147, 148; and air, Harvey, on, 29; animal, 22, 25, 127; Aristotle's view of, 21; and blood, 117, 120, 127, 133; Columbus on, 27, 30; Erasistratus's view of, 21; Galen's view of, 22, 27; Harvey's view of, 28, 31, 33, 127; Hippocrates's view of, 20; and innate heat, 126, 129; natural, 25, 27; and nervous system, 31; psychical, 23; in semen, 119, 128, 140, 148; vital, 22, 24, 27. _Spiritus_, 20, 147. Spontaneous generation, 143, 145, 152. Sun and fire, 150. Sun and generation, 145, 151. _Taenia_, 42. Thales, 111. Tissues, feeding of, and circulation, 7. Torricelli, Evangelista, 96. Tricuspid valve, 55. Universe of Aristotle, 121. Uranus, 149.