an Attempt to ascend Chimborazo. 95 



.and we wished at least to reach the station where that learned 

 traveller stopped. Those who ascend mountains are always 

 much inclined to sit down after meeting with discouragement, 

 and we placed ourselves on the station of the Peha Colorado (the 

 red rock). It was the first repose we had enjoyed. We all 

 suffered from excessive thirst, and in order to satisfy it, our 

 first occupation was to suck fragments of ice. 



Itjwas a quarter from 1, and we experienced considerable 

 cold. The thermometer had fallen to 0°4! cent. We were en- 

 veloped in a cloud. The hair-hygrometer indicated 91°5 ; and 

 after the cloud was dispersed it remained at 84°. Such a degree 

 of moisture at so great a height might appear remarkable ; but 

 I have often remarked the same thing on the Andes, and it 

 seems to be quite capable of explanation. 



During the day the surface of the snow is generally moist ; 

 the rock of Peha Colorada, for example, was quite wet ; the air 

 immediately round the glacier might therefore be saturated with 

 moisture. On Mont Blanc Saussure saw his hygrometer stand 

 at between 50° and 51°, while the temperature varied from 0°5 

 to 3°3 R. It is not rare, even at the surface of the sea, to meet 

 with a similar hygrometrical condition of the air. In the Cor- 

 dilleras there are great drynesses on the plateaus of 2000 or 

 3500 metres in height. At Quito and Santa Fe de Bagota, as I 

 have mentioned in another memoir % the hygrometer has been 

 observed to fall to 26°. 



The misfortunes which have befallen people who visited gla- 

 ciers, and especially the frequent deep cracks of the skin of the 

 face, cannot, therefore, in my opinion, be produced by the extreme 

 dryness of the air. These injuries seem to me, at least chiefly, 

 caused by the too strong light, since, in order to preserve the face 

 from all rents, it is merely necessary to cover it with a simple 

 piece of coloured crape,— a substance so open in its texture, can- 

 not, it is evident, protect the skin from the air, but it is sufficient 

 to moderate the intensity of the light to which one is exposed when 

 the sun shines on the surface of the snow. I have been assured 

 that it is sufficient to blacken the face in order to prevent the 

 disagreeable effect of the light. I am so much the more in- 



* Recherches sur la Cause qui produit le Goitre. §c. Annal. de Chim. et de 

 Phys. v. xlviii. p. 41. 



