xiv RESPIRATION 



pressure of the mixed alveolar air, 148. — With the same alveolar oxygen pres- 

 sure there is less anoxaemia at low atmospheric pressures than at normal atmos- 

 pheric pressure, 148. — Anoxaemia due to hindered diffusion of oxygen into the 

 blood, 149. — Poisoning by lung-irritant gases, 150. — Arterial anoxaemia in 

 pneumonia, 150. — Observations of Stadie, Harrop, and Meakins, 151. — The 

 clinical administration of oxygen, 152. — Description of apparatus for the pur- 

 pose, is^^^Anoxaemia during muscular exertion, 156. — Exjyeriments of Briggs 

 on oxygen inhalation during muscular exertion, 157. — Anoxaemia and 

 velocity of chemical reaction in the formation of oxyhaemoglobin, 158. — 

 Anoxaemia due to defective oxygen-carrying power of the blood, 158. — Evidence 

 that the symptoms of CO poisoning are due to anoxaemia, 160. — CO is not 

 oxidized in the body, but passes in and out by the lungs, 160. — Popular errors 

 as to the effects of CO poisoning and anoxaemia generally, 160. — Relation be- 

 tween percentage of CO in air and percentage saturation of the blood with CO, 

 160. — Relation between percentage saturation of the blood and symptoms, 161. 

 — Causes of certain differences between the symptoms of CO poisoning and 

 those of anoxaemia produced in other ways, 162. — Alteration of the dissociation 

 curve of oxyhaemoglobin in CO poisoning, 165. — Acclimatization to CO poison- 

 ing, 166. — Occurence of NO haemoglobin in the body, 166. — Methaemoglobin- 

 forming poisons, 166. — Evidence that with these poisons death is due to anox- 

 aemia, 167. — Recovery from methaemoglobin-forming poisons, 167. — Hae- 

 molytic poisons, 168. — Anaemia and anoxaemia, 168. — Reasons why no anox- 

 aemia is present during rest in ordinary anaemia, 169. — Anoxaemia due to de- 

 fective circulation, 169. — Gum-saline injections in defective filling of the vessels 

 •with blood, 170. 



CHAPTER VIII. Blood Reaction and Breathing. 171 



Ordinary physiological indications of maintenance of a normal blood reaction, 

 171. — Walter's experiments on acid poisoning and the defenses against it, 171. 

 — Diabetic coma and acid poisoning, 173. — "Titration alkalinity" and alkalinity 

 of the blood, 173. — The "buffer substances" in the living body, 174. — Modern 

 conceptions of alkalinity and acidity, 175. — Osmotic pressure, molecular con- 

 centration, and molecular diffusion pressure, 176. — Ionization of molecules, 177. 

 — Ionization and reaction, 177. — Electrometric measurement of reaction, 179. — 

 Theories of acidosis and anoxaemia, 179. — Hasselbalch's electrometric de- 

 terminations of relation of CO2 pressure to reaction in blood, 182. — Experiments 

 showing that variation of alveolar CO2 pressure in the living body compensates 

 for variations in blood reaction which would otherwise occur, 183. — Barcroft's 

 experiments on the Peak of Teneriffe, 183. — Quantitative relation between varia- 

 tions of breathing and of blood reaction, 184. — Extreme delicacy of regulation 

 of blood reaction, 185. — Very small difference between the reactions of arterial 

 and venous blood, 185. — Difference in reaction between oxygenated and fully 

 reduced normal blood, 186. — Error in electrometric method, 188. — Summary of 

 evidence as to the means by which blood reaction is regulated, 188. — Dis- 

 turbance of blood reaction by anoxaemia, 189. — Physiological evidence that the 



\/blood becomes more alkaline, 189, — Gradual, but incomplete, compensation for 

 this by the kidneys and liver, 192. — This compensation mistaken for an 

 "acidosis," 192. — Relief of the anoxaemia by the compensation, 193. — Com- 

 pensatory blood changes brought about by exposure to excess of CO2, or by ex- 



^ cessive removal by CO* from the body, 193. — The amount of "alkaline reserve" 

 in the blood is no certain index of "acidosis" or "alkalosis," 194. — Experiments 



