374 Historical 



contained on the average (six analyses at different periods) 2.37% 

 of carbonic acid. 



Reaching the study of the physiological phenomena, M. Bucquoy 

 first describes the pains in the ears. 



In regard to the circulation, he gives the following table: 



Number Pulse Pulse 



of in the during the different periods Increase 



Observations open air of the compression 



10 77.85 While the air was entering 100.05 22.20 



9 77.08 After a quarter hour stay 90.12 13.04 



7 75.39 After 25 minutes 86.80 11.41 



28 76.05 After a half-hour 81.57 5.32 



11 76.59 After 1 hour 83.58 6.99 



3 76.50 After 2 hours 83.30 7.00 



So, in compressed air, the pulse rate is higher than in open air, 

 and that is true for all degrees of pressure and especially up to 2Vz 

 atmospheres. M. Bucquoy, who states here that he disagrees with 

 the authors who observed the patients, adds: 



I have, nevertheless, one observation which seems to confirm 

 what M. Pravaz says as to the sedative effect of compressed air. One 

 of my friends, M. Ritter, who went down into the caissons with me 

 in spite of a very high fever, found that his pulse fell from 95 to 75 

 after an hour's stay. (P. 24.) 



The respiratory capacity also increases, as Pravaz had already 

 said (see the following chapter) ; the following summarizing table 

 gives the average measurement of this modification: 



Number of Time Respiratory capacity 



Observations when they were made in cubic centimeters 



103 10 minutes before entering the lockchamber 2950 



103 After a halfhour stay in compressed air 3224 



103 A quarterhour after return to open air 3075 



10 After three quarters of an hour 3004 



10 After 2 hours 3000 



10 After 10 hours 2980 



10 After 15 hours 2950 



So the increase, which is constant, and which, as other tables 

 show, keeps growing up to 2 atmospheres, persists for a fairly long 

 time after the decompression. 



So M. Bucquoy adds with reason: 



Showing that this effect is not passing, that it does not cease with 

 the compression, my experiments make us anticipate the efficacy of 

 treatments of compressed air for patients whose vital capacity is too 

 small. (P. 29.) 



