42 Historical 



become accustomed to breathing the rarefied air of the highest moun- 

 tains. (P. 245.) 



But a German traveller, Dr. Meyers," 1 who in his journey around 

 the world from 1830 to 1832 stayed for some time in Peru and in 

 April, 1831, made the ascent of the volcano of Arequipa (5640 

 meters), speaks of mountain sickness in terms which recall the 

 description of Poeppig: 



At two o'clock in the afternoon we reached the summit of the 

 mountain; my strength was exhausted, and we were suffering from the 

 painful illness called sorocho. Little by little the symptoms of a nerv- 

 ous or feverish state from which we had been suffering during the 

 whole ascent had increased. Respiration took place with increasing 

 difficulty, and gradually vertigo appeared, nausea, vomiting, then nose- 

 bleed and fainting; in this condition we were forced to lie down on the 

 ground, but rest restored our strength and permitted us to walk on 

 again. 



The illness from which we were suffering deserves to be studied 

 here; all travellers have heard of it, as soon as they have set foot on 

 the coast of this country, expressing the intention of travelling in the 

 mountains. In Peru they call it sorocho, and in Quito mareo de Puna 

 or Puna. It appears under different forms. One of its symptoms, which 

 is found both in the lower regions and on the summit of the Cordilleras, 

 is a sensation of difficulty in breathing at the least effort. If one is on 

 horseback, he feels no effect of the sort; but there appears at different 

 degrees of intensity a sort of half-feverish condition, which is evidenced 

 by burning heat over the whole body, headaches, dryness of the tongue, 

 a burning thirst, and loss of appetite. The pulse rate rises to 100 or 110 

 at the slightest movement. The face reddens, the skin cracks in differ- 

 ent places so that blood issues; at the same time a general fatigue 

 appears. That is the usual condition, the first test of those who make 

 ascents, whether in Quito, Peru, Chile, the mountains of Asia or even 

 the highest of those in our Europe. . . . 



This feverish condition is made worse by exertion and also by the 

 influence of the violent, dry and cold winds which are so common in 

 the Cordillera; the well-informed residents of this country attribute 

 this illness to these winds. . . . The burning effect of the sun in lofty 

 places also helps to aggravate these symptoms ... it is a factor in the 

 headaches and the half-feverish condition. There are some persons 

 who attribute the illness to exhalations from the metallic veins and 

 deposits of sulphur so common on the summit of the Cordilleras. 



The sorocho has been compared to seasickness, and it has even been 

 said that those who are not subject to the latter are spared by the 

 former. That seems to us a mistake. The half-feverish condition which 

 we described previously is the basis of this illness, and when it becomes 

 worse, it brings on the characteristic symptoms of diseases of the brain, 

 the respiratory organs, and the digestive organs. One of these three 

 organs is always particularly affected, so that different forms of the 

 illness result. When the chest is particularly affected, difficulty in 



