568 



Experiments 



gases were made meticulously from a very special necessity which 

 is easily seen. In fact, the least error in the calculation of the 

 proportion of carbonic acid would cause an enormous error in the 

 product C0 2 x P in the high pressures. The agreement in the 

 results announced, on which I shall dwell now, is only the more 

 remarkable. 



A glance at Column 8 of the table, which contains the numbers 

 expressing the carbonic acid tension in the air which had become 



Fig. 21 — Confined air which has become lethal under pressure; carbonic 

 acid content: A, calculated proportions; B, proportions found 

 experimentally; C, superoxygenated air. 



irrespirable, completely confirms the suspicions which we had con- 

 ceived on examining Table V in points relating to high pressures. 

 In fact, the number CO, x P, when closely inspected, is never 

 constant. It diminishes from 3 atmospheres on, and this diminu- 

 tion is extremely rapid beginning with 8 atmospheres. 



