76 TRAVELS AMONGST THE GREAT ANDES, chap. in. 



I found at this place, on rocks in situ at the base of the cliffs, 

 patches of the lichen Lecanora suhftisca, L., spread over a consider- 

 able area. This was the highest point at which any lichen was 

 obtained upon Chimborazo, or during our journey amongst the 

 Great Andes of the Equator ; and, so far as I can learn, it (18,500 

 feet) is the greatest elevation at> which anything appertaining to 

 the vegetable kingdom has been found in either of the Americas.^ 

 Another lichen of the genus Gyropliora was in quantities in the 

 vicinity of the third camp (17,200-17,300 feet). 



Standing at the foot of the Southern Walls, ^ I was more puzzle^l 

 than before to understand how my predecessors could have at- 

 tained the elevations of 19,286 and 19,698 feet. According to my 

 rough computation, the height of this place was about 18,400 feet 

 above the level of the sea.^ This, it seems to me, was the spot at 

 which Humboldt and Boussingault stopped. The latter traveller, 

 in the account reprinted in Appendix H, says that his (second) 

 attempt was made by way of the Arenal. This limits his route to 

 the three vallons which have been already mentioned. He states 

 that he got his mules to a height of 4935 metres (16,224 feet), and 

 this indicates that he followed the same vallon as ourselves, for he 

 could not have got them nearly so high either in the Vallon de 

 Debris or in that of Tortorillas. He then speaks of following an 

 arete, and his account agrees with the arete of the south-west 

 ridge ; and if his narrative is to be taken in a literal sense he must 



^ There are in the Botanical Department of the British Museum some specimens 

 of a moss of the genus Orthotric7ium, collected by the Col. Hall Avho accompanied 

 Boussingault upon his attempts to ascend Chimborazo, which are said to have come 

 from a height of 18,800 feet, and to be the last trace of vegetation. I obtained 

 species of this genus upon the summit of Corazon (15,871), but did not meet with it 

 upon Chimborazo, or see mosses growing anywhere upon that mountain higher than 

 16,700 feet. 



It follows from what is said about the elevation attained by Col. Hall and 

 Boussingault that I cannot suppose these specimens actually came from so great 

 a height. 



^ A detailed sketch of a portion of them accompanies Chapter XIX. 



^ In recomputation, this has been increased to 18,528 feet. 



