Symptoms of Decompression 703 



caused by the decompression, nor did my companions. Now in the 

 bell, about 50 cm., my face prickled, and M. Sivel had the same sensa- 

 tion at 44 cm. Before 429 mm., the discomfort was already very 

 considerable, and I had the feeling of a bar across my forehead, 

 whereas there was nothing of the sort during the ascension. In the 

 bell, my pulse rate was 116 at 51 cm., 135 at 40 cm., and in the basket 

 of the balloon, it was 116 between 43 and 44 cm. The pulse rate of M. 

 Sivel was 108 at 46.5 cm. in the bell, and 110 at 43 cm. in the basket. 



I noted the ear buzzing in the ascension exactly as in the bell. 

 As the balloon descended, it seemed as if there were cotton in my ears. 

 This impression lasted till the next day, but the pain was never more 

 than very slight. As in the bell, the pain increased during the last 

 centimeters of recompression, because of the rapidity of the descent. 



In this experiment, the two aeronauts went to a pressure of 

 304 mm. of mercury, corresponding to an elevation of 7300 meters. 

 They were, consequently, much more greatly affected than I had 

 been, not having passed 418 mm., an elevation of 5100 meters; 

 nervous phenomena dominated the scene in them; dimness of 

 vision, . intellectual indolence were very noticeable in M. Croce- 

 Spinelli. M. Sivel, who entered the apparatus fasting, began to eat 

 during the decompression; he soon stopped, and as I signed to him 

 through the glass portholes to continue, he replied by a gesture of 

 disgust. 



The favorable action of oxygen was also very evident; after 

 several inhalations the distressing symptoms disappeared. At one 

 time, at very low pressures, the lips and the right ear (the only one 

 I saw) of M. Croce-Spinelli had become so purple that I was pre- 

 paring to open the cocks, when he put the oxygen tube to his 

 mouth; the effect, that is, the return to normal color, was in- 

 stantaneous. M. Croce-Spinelli told me when he had left the ap- 

 paratus, that he resorted to oxygen at that time because he could 

 hardly see his paper, which suddenly at the first inhalation ap- 

 peared to him very white, as if he were dazzled. 



In these two experiments, oxygen had been used only intermit- 

 tently, to lessen for some instants the severity of the symptoms of 

 decompression. I wanted to operate a little differently, letting the 

 discomforts come on to a certain degree, then breathing super- 

 oxygenated air continuously, still decreasing the barometric pres- 

 sure, and seeing what would happen. 



Here is the account of two experiments carried on according to 

 this procedure. 



Experiment CCLVI. March 28. I enter the apparatus at 10:55; the 

 door is closed at 11:04; my pulse rate is 58. Barometric pressure, 

 761 mm. 



