M. Humboldt on tico Attempts to ascend Chwiborarso. 301 



feet hiMier than we had been two months before, when climb- 

 ing a similar ridge on the Antisana. It is with the deter- 

 niininff of heights in climbing mountains, as with the determin- 

 ing of temperature in the heat of summer. One finds with vex- 

 ation the thermometer not so high, the barometer not so low, 

 as one expected. As the air, notwithstanding the height, was 

 quite saturated with moisture, we now found the loose rock and 

 the sand that filled its interstices extremely wet. The air was 

 still 2° 8' (37° 04' Fahr.) Shortly before, we had in a dry place 

 been able to bury the thermometer three inches deep in the 

 sand. It indicated + 5° 8' (+ 42° 44' Fahr.) The result of 

 this observation, which was made at the height of about 2860 

 toises, is very remarkable, for 400 toises lower down, at the li- 

 mit of perpetual snow, the mean heat of the atmosphere is, ac- 

 cording to many observations, carefully collected by Boussin- 

 gault and myself, only -f- 1° 6' (34° 88' Fahr.) The tempera- 

 ture of earth (sand) at -f- 5° 8' (42° 44' Fahr.) must therefore 

 be ascribed to the subterranean heat of the dolerite mountain ; 

 I do not say to the whole mass, but to the current of air ascend- 

 ing from the interior. 



After an hour of cautious climbing, the ridge of rock became 

 less steep ; but alas ! the mist remained as thick as ever. We 

 now began gradually to suffer from great nausea. The tenden- 

 cy to vomiting was combined with some giddiness; and much 

 more troublesome than the difficulty of breathing. A coloured 

 man (a mestize of San Juan), not from, selfish motives, but merely 

 out of good nature, had been unwilling to forsake us. He was 

 a poor vigorous peasant, and suffered more than we did. We 

 had haemorrhage from the gums and lips. The conjunctiva of 

 the eyes likewise, was, in all, gorged with blood. These symp- 

 toms of extravasation in the eyes, and of oozing from the lips 

 and gums, did not in the least disquiet us, as we had repeatedly 

 experienced them before. In Europe, M, Zumstein began to ex- 

 perience hsemorrhage at a much lower elevation on Monte Rosa. 

 The Spanish warriors during the conquest of the equinoctial re- 

 gion of America (during the Conquista), did not ascend above the 

 snow line, thus but little above the elevation of Mont Blanc, and 

 yet Acosla, in his Hlstoria Natural de las Ind'ias, — a kind of 

 physical geography, which may be called a master-piece of the 

 IGlh century, — speaks circumstantially of " Nausea and Spasm 



