Gases of the Blood 655 



shaking it at a higher pressure, so as to be sure, when I had brought 

 it to the desired pressure, that it really contained all the oxygen it 

 could absorb. If several analyses at different pressures were to be 

 made of the same blood, I followed the same procedure, beginning 

 with the highest; this was quite legitimate, because the quantity of 

 oxygen introduced into the apparatus under compression was al- 

 ways much greater than the blood could absorb. The pressure re- 

 corded in the experiment was the one read after the agitation and 

 the absorption had been finished. 



An important point was first determined: namely, that the in- 

 crease of the oxygen contained in the blood was quite temporary 

 and disappeared rapidly when the compression was over. The 

 following experiment proved this. 



Experiment CCX. June 20. Defibrinated dog blood. 



At normal pressure, after long agitation, contains O 20.0. 



100 cc. were put into the apparatus, and the compression was 

 carried to 12 atmospheres, with superoxygenated gas, so that the 

 oxygen tension corresponded to 44 atmospheres of air. After an agita- 

 tion which was insufficient for complete saturation, the blood con- 

 tained, per 100 cc: 2 37.7. 



I then placed in a flask the rest of the compressed blood, which 

 was very red and contained much gas in suspension; the flask was 

 whirled like a sling once, and 10 minutes after being taken from the 

 apparatus, the blood contained only 20 vol. of oxygen, as at the 

 beginning of the experiment. 



We now come to the experiments carried on with care that the 

 saturation should be complete; the pressure was made with ordi- 

 nary air. 



Experiment CCXI. June 20. Defibrinated dog blood. 



At normal pressure contained Oa 20.0. 



At 12 atmospheres contained 0-> 30.0. 



At 8 atmospheres contained O 25.7. 



At 4 atmospheres contained O- 22.8. 



Experiment CCXII. January 22. Defibrinated dog blood. 



At normal pressure contained O 20.2. 



At 18 atmospheres contained O- 28.2. 



At 9 atmospheres contained O- 25.9. 



I particularly call attention to the following experiment, which 

 was carried out with the greatest precautions. 



Experiment CCXIII. January 12. 500 cc. of blood taken from the 

 femoral artery of a very large dog. This blood is defibrinated, filtered 

 through linen, then shaken for a half hour with air at normal pres- 

 sure; it contains 14.9 volumes of oxygen. 



It is then placed in the apparatus; for each experiment, the agita- 

 tion lasts a half hour. The findings were: 



At 6 atmospheres, Os 19.2. 



At 12 atmospheres, O 26.0. 



At 18 atmospheres, O* 31.1. 



