Incoming nerve-currents, 9. Terminal organs, 10. 'Specific energies,' 11. Sensations cognize qualities, 13. Knowledge of acquaintance and knowledge-about, 14. Objects of sensation appear in space, 15. The intensity of sensations, 16. Weber's law, 17. Fechner's law, 21. Sensations are not psychic compounds, 23. The 'law of relativity,' 24. Effects of contrast, 26. CHAPTER III. SIGHT 28 The eye, 28. Accommodation, 32. Convergence, binocular vision, 33. Double images, 36. Distance, 39. Size, color, 40. After-images, 43. Intensity of luminous objects, 45. CHAPTER IV. HEARING 47 The ear, 47. The qualities of sound, 43. Pitch, 44. 'Timbre,' 45. Analysis of compound air-waves, 56. No fusion of elementary sensations of sound, 57. Harmony and discord, 58. Discrimination by the ear, 59. CHAPTER V. TOUCH, THE TEMPERATURE SENSE, THE MUSCULAR SENSE, AND PAIN 60 End-organs in the skin, 60. Touch, sense of pressure, 60. Localization, 61. Sensibility to temperature, 63. The muscular sense, 65. Pain, 67. CHAPTER VI. SENSATIONS OF MOTION 70 The feeling of motion over surfaces, 70. Feelings in joints, 74. The sense of translation, the sensibility of the semicircular canals, 75. CHAPTER VII. THE STRUCTURE OF THE BRAIN 78 Embryological sketch, 78. Practical dissection of the sheep's brain, 81. CHAPTER VIII. THE FUNCTIONS OF THE BRAIN 91 General idea of nervous function, 91. The frog's nerve-centres, 92. The pigeon's nerve-centres, 96. What the hemispheres do, 97. The automaton-theory, 101. The localization of functions, 104. Brain and mind have analogous 'elements,' sensory and motor, 105. The motor zone, 106. Aphasia, 108. The visual region, 110. Mental blindness, 112. The auditory region, mental deafness, 113. Other centres, 116. CHAPTER IX. SOME GENERAL CONDITIONS OF NEURAL ACTIVITY 120 The nervous discharge, 120. Reaction-time, 121. Simple reactions, 122. Complicated reactions, 124. The summation of stimuli, 128. Cerebral blood-supply, 130. Brain-thermometry, 131. Phosphorus and thought, 132. CHAPTER X. HABIT 134 Its importance, and its physical basis, 134. Due to pathways formed in the centres, 136. Its practical uses, 138. Concatenated acts, 140. Necessity for guiding sensations in secondarily automatic performances, 141. Pedagogical maxims concerning the formation of habits, 142. CHAPTER XI. THE STREAM OF CONSCIOUSNESS 151