xii CONTENTS. 



CHAPTER III. 



ON THE MORE GENERAL FEATURES OF NERVOUS TISSUES. 



PAGB 



88. The general arrangement of the nervous system. Cerebro-spinal 

 and splanchnic or sympathetic system ; somatic and splanchnic 

 nerves 139 



89. Grey matter and white matter of the central nervous system. Struc- 

 ture of a nerve cell of the spinal cord ; axis-cylinder process. 

 Functions of nerve cells 143 



90. Keflex actions ; the machinery required. The circumstances deter- 

 mining the nature of a reflex action. Reflex actions often pur- 

 poseful 144 



91. Automatic actions .......... 146 



92. Inhibitory nerves 148 



CHAPTER IV. 

 THE VASCULAR MECHANISM. 



SECTION I. 

 THE STRUCTURE AND MAIN FEATURES OF THE VASCULAR APPARATUS. 



93. The chief work of the blood carried on in the capillaries and other 



minute vessels 149 



94. The main features of the vascular apparatus 150 



SECTION II. 

 THE MAIN FACTS OF THE CIRCULATION. 



95. Behaviour of arteries contrasted with that of veins . . . 153 



96. Blood pressure in an artery and in a vein 154 



97. Methods of registering blood pressure ; mercurial manometer. 



Kymograph. The blood pressure curve 156 



98. Characters of the blood pressure in various arteries and veins. 

 Blood pressure in the capillaries. Fall of blood pressure in the 



minute vessels 159 



99. The circulation through the capillaries, and small vessels. Periph- 

 eral resistance 161 



Hydraulic Principles of the Circulation. 



100. The three main physical facts of the circulation ; the central pump, 



the peripheral resistance, and the elastic tubing . . . 163 



