Gases of the Blood 659 



only by simple solution in the ambient serum. That strongly 

 recalls the mode of union of the carbonic acid with the alkaline 

 bases, whose protocarbonates are indecomposable by a vacuum, 

 whereas the deuto-carbonates at very low barometric pressures 

 lose their second equivalent of acid, as we have known since the 

 research of H. Rose. The whole blood then would behave towards 

 oxygen as a solution of bicarbonate of soda does towards carbonic 

 acid. In both cases, it is 1.) in solution in water and its proportion 

 there can be indefinitely increased according to Dalton's Law; 2.) 

 in union easily dissociated by a vacuum aided by heat; 3.) in union 

 unaffected by a vacuum and heat. 



This resemblance is very striking if we note the manner in 

 which this gas leaves the blood when the blood is agitated with air 

 at different barometric pressures. 



The agitation of blood with pure air, at normal pressure, very 

 slowly takes from it a part of its carbonic acid, without being able 

 to take it away altogether. If the air is expanded, the gas escapes 

 a little more quickly. However, the experiments which have just 

 been reported above show that, even at quite low pressures, the 

 blood does not lose its carbonic acid quickly. However, this gas 

 leaves the blood in slightly larger proportions than the oxygen; 



C0 2 



so we see the proportion lose value directly as the decompres- 



o 2 



sion is increased (Exp. CXCIX, CC, and CCI) . 



On the other hand, when I brought about a progressive vacuum 

 on blood placed in the mercury pump, I found that the acid left 

 the blood in considerable proportions only at very low pressures, 

 almost at the same time as the oxygen. In other words, the bicar- 

 bonates and the alkaline phospho-carbonates behave in the vicinity 

 of a vacuum like the deutoxy-hemoglobin of which I was speaking 

 a little while ago. 



1 Note sur les analyses du ga? du sang; influence de I'eau.— Proceedings, vol. LXXIV, 

 p. 330; 1872. The memoir is published in full in the Journal de I'Anatomie et de la Phvsiologie, 

 vol. VIII, p. 187-200; 1872. 



2 The numbers expressing the volumes of the blood gases have always been reduced to the 

 temperature of 0° and the pressure of 76 cm. 



* Du siege des combustions respiratoires. Journal de I'Anatomie et de la Phvsiologie, 

 vol. II, p. 302-322; 1865. 



4 Lecons, etc., p. 119. 



5 Des gas du sang. Archives de Phvsiologie, vol. IV, p. 5-26, 190-203, 304-318, 447-469, 573-587, 

 HO -731; 1871. 



• Lecons, etc., p. 130 et seq. 



7 Lecons sur la physiologic de la respiration, p. 161. 

 s Comptes rcndus de la Societe de Biologie for 1871, p. 61. 

 »Trait6 de physioloqie, Third edition, vol. V, p. 592; 1868. 

 10 Comptes rendus de I'Academie des sciences, vol. LXXVI, p. 440; February, 1873. 



