260 Historical 



M. Jourdanet summarizes his opinion in the following proposi- 

 tions: 



1. The corpuscles and the barometric pressure regulate the quan- 

 tity of oxygen in the blood; 



2. Disturbances in either of these two forces must necessarily 

 affect hematosis; 



3. Since oxygen is the chief vital agent, its decrease for lack of 

 corpuscles causes the weakness of anemic patients; its decrease in the 

 blood for lack of pressure must produce the same result; 



4. For this reason persons breathing the atmosphere of great 

 elevations must have their health affected in the same way as those 

 suffering with anemia at lower levels; 



5. The anoxemia of altitudes is therefore analogous to the hypo- 

 corpuscular anemia of the sea level. (P. 21.) 



Since plethoric persons have a large proportion of corpuscles 

 in their blood, it is not surprising, as M. Jourdanet says, to see 

 them often: 



Climbing the rugged sides of Popocateptl and at an altitude of 



17,700 feet imbibing the complete elements of life, whereas their 



travelling companions, of less sturdy constitution, succumbed to 

 mountain sickness. (P. 22.) 



Then making a more detailed study of the chief phenomenon, 

 the general trend of which he indicated previously, and taking 

 into account the experiments of Magnus and M. Fernet and his 

 own, M. Jourdanet reaches the remarkable conclusions which we 

 give verbatim: 



1. From 76 to 65 centimeters, partial vacuum acts only upon the 

 part of the gases of the blood which is held in true solution; 



2. Under the influence of this first barometric decompression, the 

 release of carbonic acid is mmh greater than the loss of oxygen, 

 the result of which is greater freedom of action for the oxygen; 



3. It is possible then that, since a moderate elevation does not 

 noticeably decrease the quantity of the oxygen in the blood, whereas 

 it removes a considerable portion of carbonic acid, it may act upon 

 man with a tonic and strengthening effect; 



4. As to the portion of oxygen which a weak affinity allows us 

 to consider as being held by chemical action, its escape from the 

 blood results from lowered barometric pressure only when the pres- 

 sure approaches 60 centimeters; 



5. We therefore should consider that the quantity of oxygen in 

 the blood is seriously diminished beginning in the neighborhood of 

 this limit, and it is then that the anemia of altitudes begins; 



6. We can therefore understand that a moderate altitude may be 

 a powerful means of curing anemia, whereas this same disease is a 

 natural consequence of sojourn at a considerable altitude. (P. 37.) 



