MOUNTAIN -SICKNESS. IOI 



arterial blood proceeds from the heart to revive the whole 

 organism. 



Up to a height of 16,400 feet, man can easily acclima- 

 tize himself to the rarefied air. Baron Humboldt saw Peru- 

 vians cultivating the land at Antisana, situated 13,454 feet 

 above the level of the sea; and agricultural labour requires 

 the development of an amount of force incompatible with 

 mountain-sickness, even though an energy like that of our 

 European cultivators may not be found. Jacquemont visited 

 villages in Thibet at a height of 16,400 feet. La Paz is 

 situated on the Andes at a height of 12,195 feet, but the 

 inhabitants suffer no inconvenience from the rarity of the 

 atmosphere; though strangers can walk only a short distance 

 without stopping, and they are specially uncomfortable if the 

 young Peruvian ladies mischievously invite them to a few 

 turns in a waltz. It is hardly necessary to remark that these 

 symptoms are not equally urgent in all those who expose 

 themselves to this rarefied air. Some individuals scarcely 

 feel them, and are soon acclimatized, while others suffer 

 greatly for a long period. A host of circumstances and 

 special conditions contribute also to render these symptoms 

 more or less marked, and mountaineers themselves some- 

 times experience them as well as the inhabitants of less ele- 

 vated countries. 



