914 Experiments 



After blood comes urine, which, as Experiment DCX showed, 

 may contain as much as 106 volumes of CO, per 100 volumes of 

 liquid. 



Finally, the tissues in analysis show that their C(X content is 

 proportionate to the amount of blood they contain; Experiment 

 DCXX is quite characteristic in this regard; the kidneys and the 

 liver, which are very vascular organs, contained per 100 volumes 

 62 and 64 volumes of CO.,; the muscles had 42, the brain only 26. 



The combined experiments made on the muscles of dogs or the 

 entire bodies of sparrows seem to show that from the bodies of 

 animals killed by carbonic acid one can extract about 40% of its 

 volume of this gas; on the other hand, they give us the idea that in 

 the normal state there exists there only about 10% to 15%. It 

 would then be about 25% to 30% of the total volume of the animal 

 which would represent the quantity of carbonic acid formed and 

 not exhaled during the stay of the animal in closed vessels. Now 

 Experiment DCVIII shows us definitely that a dog weighing 3.950 

 kilos removed from the superoxygenated medium in which it died 

 about 1300 cc. of oxygen, which must have been transformed into 

 carbonic acid and remained in its blood and tissues. 



These results, we see, agree very well, but we must not at- 

 tribute to them extreme accuracy: from a third to a half of the 

 volume of the body seems to be the quantity of carbonic acid re- 

 tained in the tissues by an animal before dying from the action of 

 this gas. 



This explains why, as I saw in the early experiments, the details 

 of which it would be useless to report here, if a dog is caused to 

 breathe oxygen contained in a bag of small dimensions, the animal 

 absorbs all the gas from the bag and then dies from simple lack of 

 air. All the oxygen of the bag has remained in the tissues in the 

 form of carbonic acid. 



4. Symptoms and Mechanism of Poisoning by Carbonic Acid. 



Now that this important point is established, we should study 

 the symptoms and mechanism of this poisoning by gradual ab- 

 sorption of carbonic acid in all the tissues. 



Let us first consider the progressive course of the change in the 

 superoxygenated air which the animal is breathing. The graphs 

 of Figure 75, which express the results of Experiment DCXV, show 

 us very clearly what is taking place. 



On the horizontal axis are marked in hours the time elapsed 



