950 Summary and Conclusions 



I have read many strange articles on this subject. I shall quote 

 only one, however, because it had the honor of insertion in the 

 Official Journal, 3 and because it can serve as a model in this common 

 art of hiding ignorance behind pompous scientific terms: 



To have a satisfactory explanation of mountain sickness, we must 

 use modern knowledge of human physiology and physics. The cause 

 of these phenomena was at first thought to be the increasing rarefac- 

 tion of the air as one ascends. 



The diminution of density of atmospheric strata does indeed pro- 

 duce an acceleration of pulse and respiration; but these symptoms 

 remain isolated and are often unnoticed by aeronauts at heights much 

 greater than those at which mountain sickness appears. Increase in 

 frequency and depth of respirations compensates for the rarefaction 

 of the air. Furthermore, oxygen in this case, though it is less abun- 

 dant, appears to be better fixed and dissolved in the blood, a fact which 

 lessens by so much the inconveniences of its rareness. 



However this may be, ascent into the upper regions of the air, 

 if it has a certain effect, possesses it only in a secondary way as if to 

 make more noticeable and more speedy the effect of the increased 

 labor which walking requires; for it is in the increase of mechanical 

 labor that we find the real reason for mountain sickness. 



To maintain animal warmth and life, man in repose requires a 

 determined quantity of heat, furnished by hydrogen and carbon. Ac- 

 cording to modern theories, all mechanical labor is the result or the 

 transformation of an equivalent quantity of heat supplied by inner 

 combustion. 



This heat, transformed into labor, does not raise the temperature 

 of the body; but it cannot be produced without giving the usual 

 residues, which are, we know, carbonic acid and water vapor. The 

 increase in labor caused by exhausting ascents consumes in the blood 

 the materials of heat production, and produces an excess of carbonic 

 acid, of which the system rids itself by speeding up respiration. Even 

 this outlet is often insufficient; and hence the phenomena which we 

 have described, and which are all the more marked because the trav- 

 eller is in a cold region; and hence too the speed with which they 

 disappear when the traveller rests, and requires from his breathing 

 only the heat necessary for his existence. 



The excess of carbonic acid is removed and everything becomes 

 normal. 



There are some who have protested in the name of the ancient 

 theories, and have revived the unfortunately classic ideas about the 

 decrease of the weight supported by the body, hemorrhages by 

 suction, and the peripheral cupping-glass. I reported earlier the 

 strange discussion begun in the Academy of Medicine, and the 

 opinion of M. Colin on the role played by expanded intestinal gases. 



Dr. Chabert, 4 in a recent thesis, after reporting and adopting 



