990 Summary and Conclusions 



yet, if, in the midst of a sort of muscular., sensorial, and intellectual 

 inertia of which they are victims, they wish to make even a slight 

 movement, to raise an arm like Glaisher and Tissandier, they sud- 

 denly perceive that paralysis has struck them unawares, and almost 

 immediately, since the brain to which a weakened heart sends a 

 blood insufficiently oxygenated ceases its duty, there comes a loss 

 of consciousness which, if the balloon does not descend, may lead 

 rapidly to death. 



Prophylaxis. The analysis which we have just made shows the 

 usefulness of a certain number of precautions which common sense 

 had already suggested. Aeronauts planning very lofty ascensions 

 ought as much as possible in the preceding days to avoid excess 

 of muscular, nervous, and intellectual fatigue. Although in good 

 health ordinarily, especially from the point of view of respiratory 

 and circulatory organs, they must guard against attacks of bron- 

 chitis, which hinder the respiration. Before starting, they should 

 take a meal of substantial food and take with them some cheering 

 victuals to eat frequently on the way. 



They should try to arrange everything in the basket so as 

 to avoid making great muscular efforts; the bags of ballast, for 

 example, should be emptied by cutting a cord, and not lifted from 

 the bottom to the edge of the basket. A comfortable arrangement 

 will not be simply luxury, it will save the consumption of oxygen. 



Let us add that rugs, bottles of hot water or, better, hot oil, 

 should be taken along to keep away the cold, which also consumes 

 oxygen. 



Prudence would dictate that they slacken the ascent when they 

 reach the upper strata, so as not to be subjected to over-sudden 

 changes. Unfortunately that is almost never possible in practice, 

 for if the course of the balloon is slackened, the gas contained in 

 it will grow cold on contact with the icy layers of the air, and 

 the balloon will lose part of its ascensional power. Now there is 

 never too much for such expeditions, and as much ballast as pos- 

 sible must be kept for the accidents of the descent, in which the 

 balloon, almost empty, behaves almost like a simple parachute. 



Such are the precautions whose utility was observed before 

 my work. But today, though still useful, they are far less im- 

 portant than the respiration of superoxygenated air. Thanks to 

 this, and to this alone, all the dangers of decompression can be 

 braved with impunity. I have verified this experimentally upon 

 myself, as you have seen, 



