Diving Bells and Suits 395 



For 6 months, I have had about a hundred men diving at depths 

 varying from 30 to 40 meters. 200 other foreign divers were working 

 under my supervision under the same conditions. All these men were 

 breathing air at the pressure of the ambient medium, about 4 or 5 

 atmospheres. 



Five men died at these pressures, a great many others were 

 attacked by different affections, the most frequent of which were 

 paralyses of the lower limbs and the bladder, deafness, and finally 

 anemia. 



The men subjected to sudden decompressions were really more 

 affected by the symptoms than the others. Those who died never 

 expired at the bottom of the water, they came up complaining of 

 inward pains, particularly of the heart, lay down in their boat, and 

 died after a few hours. 



July 19, 1872, a young doctor who in 1868 had made a cruise on 

 board a boat bound for sponge fishing on the coast of Turkey, 

 Alphonse Gal, 35 sustained before the Faculty of Montpellier a very 

 interesting thesis on the data which he had observed. 



In the first part of his work, he discusses the modifications in 

 the physiological functions caused by a stay in compressed air. 

 Naturally I am reporting only the part of the observations which 

 come from his experience. 



Speaking first of respiration, he says: 



It is impossible to use a spirometer in a diving suit; and it is rather 

 difficult to appraise sensations of the type that we were studying. 

 However, at pressures varying from 15 to 25 meters, I observed myself 

 from the point of view of respiratory movements and I think that the 

 expansion is less than in the normal state. No doubt the pulmonary 

 capacity, which M. Bucquoy calls the vital capacity, increases, in the 

 inspirations in which the lungs are called upon for their full strength; 

 no doubt when one is making an experiment and tries to produce the 

 fullest expansion, the results are better in the compressed air; no 

 doubt also the patient subjected to the air treatment and quickly 

 experiencing a sensation of well-being "due to the greater efficiency 

 of hematosis, instinctively takes deeper inspirations; but the diver, 

 subjected to a pressure of 2, 3 and 4 atmospheres, does not feel the 

 necessity of increasing his pulmonary expansion, and like Foley, I 

 believe in the action of the nervous centers in moderating the extent 

 of the inspiration, since this extent has become useless because of 

 the greater quantity of oxygen brought in contact with the capillaries 

 of the pulmonary plexus in a volume which merely equals the normal 

 volume. 



And so in summary, for forced respirations the pulmonary capacity 

 increases with the atmospheric pressure; but for ordinary inspirations, 

 especially in a healthy man, this rule no longer holds, for one is more 

 likely to observe — at least I think I noted it, especially at pressures 

 of 2 to 3 atmospheres — a decrease in the pulmonary amplitude (P. 17). 



In regard to the number of respiratory movements: 



