CONTENTS. 



xxi 



The Relations of Oxygen in the Blood. 



PAGE 



§ 274. The absorption of oxygen by blood is not according to ' the law of 



pressures ' 447 



§ 275. The characters of haemoglobin 450 



§ 276. The spectroscopic features of haemoglobin 451 



§ 277. The spectroscopic features of reduced haemoglobin .... 453 



§ 278. The oxygenation and reduction of haemoglobin .... 455 



§ 279. The colour of venous and arterial blood 455 



§ 280. Carbonic-oxide-hsemoglobin 457 



Products of the Decomposition of Haemoglobin. 



§ 281. Haemoglobin splits up into hamiatin and a proteid .... 458 



§ 282. The features of haematin. Haeinin. Methsemoglobin . . . 460 



The Relations of the Carbonic Acid in the Blood. 



§ 283. The carbonic acid of the blood not simply absorbed . . . 401 



The Relations of the Nitrogen in the Blood. 



§ 284. The nitrogen simply absorbed 461 



§285. 



§286. 

 §287. 



§288. 



SECTION IV. 



The Respiratory Changes in the Lungs. 



The relations of the oxygen of the blood to pressure. Association 

 of oxygen with, and dissociation from haemoglobin. The 



problem stated 462 



The experimental evidence 464 



The relations of the oxygen in laboured breathing and asphyxia . 465 



The Exit of Carbonic Acid. 



The exit of carbonic acid from the blood into the pulmonary alve- 

 olus the result of ordinary diffusion 466 



SECTION V. 

 The Respiratory Changes in the Tissues. 



§ 289. The oxidations of the body take place mainly in the tissues and not 

 in the circulating blood. The respiration of muscle . 



§ 290. The respiration of other tissues. The taking in of oxygen separate 

 from the giving out of carbonic acid 



§ 291. A summary of respiration in its chemical aspects .... 



467 



469 

 470 



SECTION VI. 



The Nervous Mechanism of Respiration. 



§ 292. Respiration an involuntary act. The efferent nerves, the respiratory 



centre 472 



