x CONTENTS. 



The Chemistry of Muscle. 



PAGE 



58. Contrast of living and dead muscle ; rigor mortis .... 95 

 59. Chemical bodies present in dead muscle ; myosin, syntonin . . 96 

 60. Chemistry of living muscle ; muscle-plasma, muscle-clot and muscle- 

 serum, myoglobulin, histo-hsematin 98 



61. Acid reaction of rigid muscle; development of carbonic acid in rigor 



mortis 99 



62. Other constituents of muscle 101 



63. Chemical changes during contraction ; development of carbonic acid 



and acid reaction 102 



64. Summary of the chemistry of muscle 104 



Thermal Changes. 



65. Heat given out during a contraction. Comparison of muscle with a 



steam engine 104 



Electrical Changes. 



66. Non-polarisable electrodes. Muscle currents ; their distribution and 



nature 106 



67. Negative variation of the muscle current; currents of action. The 



rheoscopic frog Ill 



The Changes in a Nerve during the passage of a Nervous Impulse. 



68. Structure of a nerve. Primitive sheath or neurilemma, medulla, axis 



cylinder, nodes of Eanvier. The axis cylinder the essential part 113 

 69. Nerve endings in striated muscular fibres. Henle's sheath. End- 

 plates 118 



70. Non-medullated nerve fibres 120 



71. The chemistry of a nerve; cholesterin, lecithin, cerebrin, protagon . 121 

 72. The nervous impulse; the electrical changes accompanying it. These 



changes travel in both directions along the nerve . . . 123 

 73. Summary of the changes occurring in a muscle and nerve as the 



result of stimulation , ... 125 



SECTION III. 



THE NATURE OP THE CHANGES THROUGH WHICH AN ELECTRIC CURRENT 

 IS ABLE TO GENERATE A NERVOUS IMPULSE. 



Action of the Constant Current. 



74. Action of the constant current; making and breaking contractions . 126 

 75. Electrotonus. Effect of the constant current on the irritability of 



the nerve. Katelectrotonus. Anelectrotonus . . . . 128 



76. Electrotonic currents 130 



77. Kelation of electrotonus to nervous impulses, and to the effects of 



the constant current 132 



8 78. Action of the constant current on muscle . . . 134 



