Mountain Journeys 57 



hardly 4 or 5 millimeters. The alpacas and the vicunas live in herds at 

 these heights, the condors fly far above, and I have found a few turtle- 

 doves there. Although accustomed to the pressure of Oruro, when I 

 went to these mines, I was always ill, with nausea, headache and dif- 

 ficulty in breathing, and I could not walk eight or ten steps without 

 having to stop to get my breath. The manager, who has lived there 

 for two years, could walk a little further, but always had difficulty in 

 breathing. At a height of 4,000 meters, the rarefaction of the air has 

 only a passing effect upon the health, the residents of Oruro and 

 Potosi become very old, and lung diseases are unknown there; the 

 residents are generally thin, very active, but have little strength, which 

 perhaps is partly due to their almost exclusively vegetable diet. 



In Chile, the highest point I reached was on the side of Aconcagua 

 at an altitude of 5,832 meters; the summit has an elevation of 6,834 

 meters. At the point where I stopped, the barometer reading was 

 382 mm.; I was very sick and it was impossible for me to climb higher; 

 my eyes were badly bloodshot; all objects, even the snow, seemed red 

 to me, and even with my glasses of very dark blue glass, I had great 

 difficulty in reading my barometer. On the way down, at about 5,000 

 meters, all these symptoms disappeared. 



In my numerous stops in the region of the Andes, I often saw 

 condors wheeling about the sides of the highest mountains, but never 

 soaring above their summits; but one should not be hasty in drawing 

 a conclusion from that fact; for the heights they reach are so great that 

 they appear only as little black dots; if there were any at the height 

 of the summit of Aconcagua, they would certainly be invisible, even 

 if one were at an elevation of 5,000 meters, that is, higher than Mont 

 Blanc. At 4,000 meters one finds in the Andes of Chile guanacos, swans, 

 ducks, turtledoves, and even humming birds. 



A. Pissis. 



If travellers who limited themselves to crossing the passes of 

 the Cordillera or stopping on the lofty inhabited plateaux of Bolivia 

 and Peru have experienced such symptoms, one may suppose that 

 those who purposely attempted the ascent of the mountains which 

 tower above the average level of the chain have experienced even 

 more. However this is not always true. We have seen that Hum- 

 boldt and Boussingault suffered much less on Chimborazo than 

 other travellers at Cerro de Pasco or even La Paz. Other examples 

 are no less strange. 



For instance, on January 14, 1845, Wisse 5G descended into the 

 crater of Rucu-Pichincha to the depth of "four times the highest 

 pyramid of Egypt", and climbed back; he does not mention any 

 physiological symptom. 



We shall discuss these differences later. They are so great that 

 certain travellers go so far as to deny that mountain sickness exists, 

 because they never experienced it, and there reappear the explana- 



