210 Historical 



molecules of antimony, sulphur, arsenic, and others, to which they 

 attribute these symptoms. 



But the objection may be raised that if this opinion were well 

 founded, the men who ride on these animals would experience the 

 same distress when they have stopped, which is not the case. We 

 must therefore believe that it is due only to the extreme rarity of the 

 air, which is filled, moreover, with some foreign body disseminated in 

 it, although this foreign substance does not come from the pores of the 

 earth. We may also say that it is not probable that there are minerals 

 enclosed within all these peaks where the symptoms occur, since we 

 see no outer sign revealing them; if it were so, there would be no 

 mountain or slope in these chains, covering several hundred leagues, 

 in which one would not find some mineral. (P. 116.) 



Ulloa also says a few words about symptoms which are much 

 less serious, but which his successors did not always have the 

 sagacity to distinguish, as he did, from mountain sickness: 



The dry, rare air causes such dryness that the epidermis, and 

 especially the skin covering the lips, chaps and cracks; this causes 

 pain, and soon blood issues from them; the hands become rough and 

 scaly: this roughness is particularly noticeable on the joints and upper 

 part of the fingers, the scales are thicker there than elsewhere, and 

 they take on a darkish color which is not removed by lotions. These 

 affections are called chugno, a term which the natives use for anything 

 that is wrinkled and hardened by the cold. (P. 111.) 



All these data were known to the illustrious Haller, who re- 

 views them briefly in the third volume 19 of his immense work, 

 and tries to explain them with the data of the physics, chemistry, 

 and physiology of his time. The mechanical influence of the pres- 

 sure of the air seems to him absolutely predominant. In his dis- 

 cussion, he utters this very strange idea, already suggested by 

 Cigna, that the air of altitudes would act on the organism in a 

 less painful manner than that which was rarefied to the same de- 

 gree under the pneumatic bell-jars: 



The air (he says) weighs upon the body of man from all sides 

 . . . and different authors estimate this weight at variable amounts 

 from 31,144 to 42,340 pounds. Children are more compressed propor- 

 tionately than adults, since the surface of their bodies diminishes less 

 than the mass. 



All of this varies in the same locality, because the mercury of the 

 barometer rises or falls about three inches, and thence come differ- 

 ences which have been estimated at from 3062 to 3982 pounds. The 

 variation is much greater if we compare the air of the highest moun- 

 tains to that of the deepest coal mines ... In this case, it may go 

 from 36,292 to 19,281 pounds (according to La Condamine, it would be 

 only 17,000 pounds on the top of Chimborazo, which is an inaccessible 

 peak anyway). And this difference appears even much greater, if in- 



