Gases of the Blood 945 



Experiment DCLXVII. August 20. Dog, fasting. 



Arterial blood: CO. 54.0. 



After agitation for 5 hours with pure carbonic acid, the blood con- 

 tains 166 volumes of CO, at 22°. 



The coefficient of solubility being 90.1, we see that the bases lacked 

 22 volumes of CO, for saturation. 



Experiment DCLXVIII. July 24. Old horse, exhausted, paralyzed 

 in the hind quarters; one of the sympathetic nerves in the neck has 

 just been cut. 



Drew carotid blood on the side of the sympathetic that was cut. 

 It contains O. 11.8; CO, 44.8. 



At the same time took venous blood from a branch of the jugular; 

 it contains O- 11.8; C0 2 54.0. 



Before sectioning, the venous blood had given C0 2 50.1. Shaken 

 for 24 hours, with pure C0 2 contains (temperature 19°) 178.2 volumes 

 of CO;. It has taken on a very strange dark color, which I have never 

 seen. 



Coefficient of solubility at 19° : 92.5. Therefore, there is lacking 

 for complete saturation of the bases of the arterial blood 40.9 volumes 

 of CO;, and for that of the venous blood before any nervous section, 

 31.7. 



We see that in none of our- experiments did the arterial blood 

 contain carbonic acid that was simply dissolved; only once were 

 the alkaline bases exactly saturated (Exp. DCLXI) . Furthermore, 

 the venous blood itself, in Experiments DCLXII and DCLXVI, con- 

 tained only carbonic acid in combination; but in Experiment 

 DCLXI, there were 20.5 volumes of dissolved CO., 



Perhaps, before drawing definite conclusions, we should make a 

 larger number of experiments; however, for the arterial blood, the 

 agreement of our analyses is perfect, and I think we can consider 

 that it is proved that all the dissolved carbonic acid (when it exists 

 in the venous blood) escapes in passing through the lungs, and that 

 the supercarbonated alkaline salts are, moreover, dissociated there 

 from a part of their acid, hardly exceeding one third. 



But this last limit may be exceeded, and a larger proportion of 

 combined carbonic acid may escape through respiration and no 

 longer be found in the arterial blood. This happens particularly 

 at the time of exaggerated respirations through a tube placed in 

 the trachea; it happens in curare poisoning, when artificial respira- 

 tion is given, even with precautions; it happens after or during the 

 convulsions due to compressed oxygen (see particularly from this 

 point of view Experiment CCLXXXVI, in which the proportion of 

 CO,, dropped to 9.9 volumes in the arterial blood) ; it happens, 

 finally, through respiration in rarefied air. The alkalinity, of the 



