OoTOJiKK 6, ]922] 



SCIENCE 



391 



the life v/ork of one of the master investisrators 

 of oui' time. It is a fit companion to the 

 volumes from the pens of previous Silliman 

 lecturers, inelucline: such names as J. J. Thom- 

 son, Sherrington, Rntherforcl, Kernst, Batesoii, 

 and Arrhenius. 



It Ijegins with a brief but illuminating ac- 

 count of the historical development of the 

 knowledge of respiration; its relation to 

 chemistry and physics on the one hand, and to 

 the theory of physiological regulation on the 

 other. The ehaptei-s following deal with car- 

 bon dioxide and the chemical regulation of 

 breathing; the nervous mechanism and control 

 and some of the nervous disturbances of res- 

 piration, as in "soldier's heart," neurasthenia 

 and fatigue; the blood as a carrier of oxygen 

 with a discussion of the properties of hemo- 

 globin and the variations of its dissociation 

 curve; the blood as a carrier of carbon di- 

 oxide and the reilations of carbon dioxide to 

 neutrality regulation in the 'blood and othei- 

 fluid media of the body; the causes and effects 

 of anoxhemia, and the importance and fre- 

 quency of oxygen deficiency as a factor in 

 functional disturbances; the mutually regula- 

 tive relations of blood reaction and breathing; 

 the much disputed question of gas secretion 

 in the lungs; tie influence of vitiation of the 

 atmosphere upon health in relation to indus- 

 trial hygiene; high atmospheric pressures and 

 caisson disease; low atmospheric pressures, 

 mountain sickness, and the physiological con- 

 ditions to which aviators are exposed; and an 

 appendix giving the speciaJized methods which 

 the author has developed for investigation in 

 this field. 



Two general aspects of Haldane's Vi'ork de- 

 serve particular notice : Other master physiolo- 

 gists — formerly Voit, and in modern times, 

 particularly Pawlow — have emphasized the 

 importance of dealing with the normal and 

 complete organism — for example, the con- 

 scious, healthy, happy, uuanaesthetized, unre- 

 strained dog. It is the failure of the general 

 run of investigators to appreciate and apply 

 this doctrine, and their attempt to infer trutli 

 directly from the essentially false conditions 

 of most experimentation — for example, much 

 of the current blood pressure experimenta- 



tion, and the reduced eirculation-^which leaves 

 so little value in most of the articles filling our 

 journal's. They deal merely (as Haldane in- 

 cisively expresses it in his preface) "with frag- 

 ments of frogs and other animals." Haldane, 

 on the contrary, more than any other physiolo- 

 gist has found ways to use as his "versuehs- 

 tier" not only the noi-mal mammalian or- 

 ganism, with functions unpreverted by experi- 

 mental conditions, but living, conscious, active 

 man. The investigator himself and his col- 

 laborators have been the chief subjects of his 

 experiments. Indeed Haldane's demonstration 

 of the possibility and the etficieney of experi- 

 mentation upon man v/ill probably in the fu- 

 ture be accounted his greatest contriljution. 

 By no other method apparently could the 

 character and uniformity of the alveolar COj 

 regulation, — the centi-al fact of the Haldanian 

 conception of respiration — have been estab- 

 lished. 



The second aspect of Haldane's thought 

 which gives it permanent philosophical value 

 is his treatment of respiration and the blood 

 as aspects and illustrations of physiological 

 regulation : that extraordinary power of every 

 living organism to maintain itself, so different 

 from, or rather so much in addition to the 

 equilibrium of an inorganic system. It is the 

 capacity to "preserve constant the conditions 

 of life in the internal envu'onment," as Claude 

 Bernard expresses it. 



This conception of "organieism" as the cen- 

 tral doctrine of biology differentiates Bernard, 

 Haldane, and others who hold it, from the 

 vitalists on the one hand, and from the mech- 

 anists on the other. It prompts the most 

 thoi'ough analysis of which our present day 

 and incomplete chemistry and physics are ca- 

 pable into the physico-chemical conditions and 

 properties of the humors and cells; but it looks 

 on this analysis as merely a preliminary and 

 sees as the essential topic of the physiologist 

 those "living" reactions and processes by which 

 the organism "preserves constant," or rather 

 adjusts, controls, and regulates, within narrow 

 limits of variation such "conditions of life" as 

 osmotic pressure, hydrogen ion concentration, 

 temperature, content of sugar, calcium, and po- 

 tassium and a thousand other elements already 



