CONTENTS. XV 



PAGJE 



The Cause of Coagulation, 245 



Coagulation in the Vessels, 247 



Formation of Fibrin, ... 248 



CHAPTER XVI. 



THE HEART. 



Pulmonary and Systemic Circulations, 251 



Method of the Circulation of the Blood, 252 



The Heart, 256 



Arrangement of Muscle Fibres, 256 



Minute Structure of the Heart, 258 



Action of the Valves, 260 



Movements of the Heart, .262 



Cycle of the Heart-beat, 263 



The Heart's Impulse, 266 



Heart-sounds, 269 



Innervation of the Heart, . .271 



Local Centres, 272 



Inhibitory Nerves, 276 



Acceleration Nerves, ........ . 277 



Afferent Cardiac Nerves, . . . 278 



CHAPTER XVII. 



THE BLOODVESSELS. 



Structure of the Vessels, 279 



The Capillaries, 281 



Kelative Capacity of the Vessels, 283 



Physical Forces of the Circulation, 285 



The Blood-pressure, 287 



Measurement of Blood-pressure, 291 



Variations in the Blood- pressure, 295 



Influence of Respiration on the Blood-pressure, 297 



The Arterial Pulse, 302 



Methods of obtaining Pulse-tracings, 304 



Variations in the Pulse, 307 



Velocity of the Blood-current, 308 



Controlling Mechanisms of the Bloodvessels, 312 



