Theories and Experiments 261 



Finally, in 1864, a third 04 work repeats with new develop- 

 ments the ideas expressed in the works from which I have just 

 taken numerous quotations. However, I cannot refrain from ex- 

 tracting from one of his chapters on mountain sickness his clear 

 explanation of this syndrome, an explanation in which we need 

 to make no important change for the conclusions of the present 

 book: 



A man who rapidly ascends to a very lofty point is deprived of 

 a certain quantity of oxygen from which he was accustomed to 

 receive a stimulating effect necessary for the full exercise of his 

 strength. Certainly, what is left him after his ascent is still capable 

 of maintaining life and even the regular action of the functions. But 

 man cannot endure without temporary symptoms a sudden reduction 

 which lessens the resources from which the nervous system is accus- 

 tomed to draw its power. The muscular fibers also refuse to perform 

 their task when their oxygen supply is decreased. We then see 

 appearing those phenomena which hemorrhages have made familiar 

 to us. As a result of the loss of blood, the organism, we know, sud- 

 denly loses an important part of its normal stimulus; the patient has 

 vertigo, his muscles weaken, nausea attacks him, and the more nearly 

 vertical his position is, the more quickly he is seized by syncope .... 

 The weakness produced by bleeding is evidently the consequence 

 of a sudden lack of oxygen through the loss of a certain quantity of 

 corpuscles, just as mountain sickness results from a more direct with- 

 drawal of the same gas. So that, beyond a doubt, an ascent beyond 

 3000 meters amounts to a barometric dis oxygenation oj the blood, 

 just as a bleeding is a disoxygenation oj the blood through the lack 

 of corpuscles. (P. 92.) 



These works soon stirred up a controversy which was very bit- 

 ter. A French expeditionary corps had just been sent to Mexico, 

 and the conclusions of M. Jourdanet were anything but encourag- 

 ing for those who dreamed of the establishment of a Latin empire 

 supported by a French colony established on the lofty plateaux 

 of Anahuac. 



Michel Levy, then director of the School of Military Medicine 

 and Surgery, was aroused and thought he should open a sort of 

 investigation of the accuracy of the data given by M. Jourdanet; 

 Dr. L. Coindet, head of the medical service of the second division 

 of the French army, agreed to take charge of this investigation. 



The first letter sent by this observer to his hierarchic chief 

 censured the statement of M. Jourdanet about the slackening of 

 the respiratory movement: 



A statement (said Michel Levy) which contradicts the opinion 

 accepted hitherto that, under the influence of reduced atmospheric 

 pressure, respiration is accelerated to compensate by the number of 



