xvi RESPIRATION 



CHAPTER X. Blood Circulation and Breathing. 257 



Intimacy of connection between circulation and breathing, 257. — The most 

 immediate need for circulation is the need for oxygen and for removal of CO2, 

 257. — The local circulation rates must be correlated in the main with these 

 needs, 258. — Special value of experiments on man, 259. — Experiments of Loewy 

 and von Schrotter with lung catheter, 260. — Experiments of Krogh and Lind- 

 hard by the nitrous oxide method, 2^2. — Yandell Henderson's experiments on 

 dogs, 263. — Experiments on "heart-lung preparations," 264. — New method in 

 which the whole of the lungs are used as an aerotonometer, 254. — Results in 

 man during rest and work, 265. — The circulation rate is rapid during rest, and 

 does not increase in direct proportion to work, 268. — The oxygen consumption 

 per heartbeat and its significance, 269. — The venous blood from different parts 

 of the body, 270. — Significance of this as regards the mixed venous blood under 

 different conditions, 270. — General conclusion as regards local regulation of 

 blood flow, 271. — Yandell Henderson's experiments on local circulation and 

 CO2 pressure, 272. — Evidence that excessive artificial respiration causes slowing 

 of the circulation and great local anoxaemia, 272. — With moderate increase of 

 CO2 percentage in the inspired air the circulation does not increase with the 

 breathing, 273. — But with great increase of CO2 percentage the circulation in- 

 creases, 274. — Increase in oxygen pressure slows the circulation, 274. — With 

 V great deficiency of oxygen there is increase in the circulation, (^^^>-^Effects of 

 —y forced breathing and muscular exertion on venous blood pressure, 275. — Gen- 

 eral conclusion as to regulation of local and general circulation, 276. — Com- 

 parison of regulation of circulation with regulation of breathing, 277. — Part 

 played by the heart in the circulation, 278. — Regulation of heart's action, 278. — 

 Coordination of contraction of muscular fibres of auricles and ventricles, 278. — 

 Start, spread, and frequency of each contraction, 279. — Regulation of filling of 

 ventricles, 279. — Nervous regulation of frequency of heartbeat, 279. — Regula- 

 tion of blood distribution, 281. — Contractility of arteries, veins, and capillaries, 

 281. — Vasomotor regulation of arterial and venous blood pressure, 283. — 

 Abnormal defects in circulatory regulation, 284. — Valvular defects and breath- 

 ing, 286. — Nervous defects and breathing, 286. — Loss of blood and its treat- 

 ment by gum-saline injections, 287. — The condition of "shock," 288. — Yandell 

 Henderson's investigations, 288. — Shock from absorption of poisonous disin- 

 tegration products, 289. — Regulation of blood volume, haemoglobin, and rate 

 of pulse and respiration in animals of different sizes, and after loss of blood or 

 transfusion, 290. — Evidence that the haemoglobin percentage of the blood de- 

 pends on the oxygen pressure in tissue capillaries, 293. — Chlorotic "anaemia" 

 and breathing, 297. — Addendum Further experiments on the circulation in 

 man, 298. 



CHAPTER XI. Air of Abnormal Composition. 300 



Outside air of country and towns: effects of impurities, 300. — Air of occupied 

 rooms. Common impurities and their effects, 302. — Effects of temperature, 

 moisture, and movement of air, 303. — General standard of air purity, 305. — 

 Critical wet-bulb temperature, 305. — The katathermometer, 306. — Escape of 

 lighting gas and conditions determining their danger, 306. — Importance of pro- 

 portion of CO in lighting gas, 310. — Air of mines. Abnormal constituents 

 present, 3 1 1 . — Black damp : composition, sources, and properties, 3 1 1 . — Fire 

 damp: composition, sources, and properties, 313. — Afterdamp from explosions 



