356 THE VICUNA. [chap. xvi. 



irrigation had formerly been conducted. There was 

 nothing in the appearance of the watercourse to indicate 

 that the river had not tiowed there a few years previously; 

 in some parts, beds of sand and gravel were spread out ; 

 in others, the solid rock had been worn into a broad channel, 

 wh ch in one spot was about forty yards in breadth and 

 eight feet deep. It is self-evident that a person following 

 up the course of a stream will always ascend at a greater 

 or less inclination : Mr. Gill, therefore, was much astonished, 

 when walking up the bed of this ancient river, to find 

 himself suddenly going down hill. He imagined that the 

 downward slope had a fall of about forty or fifty feet 

 perpendicular. We here have unequivocal evidence that 

 a ridge had been uplifted right across the old bed of a 

 stream. From the moment the river-course was thus 

 arched, the water must necessarily have been thrown 

 back," and a new channel formed. From that moment, 

 also, the neighbouring plain must have lost its fertilising 

 stream, and become a desert. 



June 2-jth. — We set out early in the morning, and by 

 mid-day reached the ravine of Paypote, where there is a 

 liny rill of water, with little vegetation, and even a few 

 algarroba trees, a kind of mimosa. From having fire- 

 wood, a smelting-furnace had formerly been built here : 

 we found a solitary man in charge of it, whose sole 

 employment was hunting guanacos. At night it froze 

 sharply ; but having plenty of wood for our fire, we kept 

 ourselves warm. 



June 2%th, — We continued gradually ascending, and the 

 valley now changed into a ravine. During the day we 

 saw several guanacos, and the track of the closely-allied 

 species, the Vicuna : this latter animal is pre-eminently 

 alpine in its habits ; it seldom descends much below the 

 limit of perpetual snow, and therefore haunts even a more 

 lofty and sterile situation than the guanaco. The only 

 other animal which we saw in any number was a small 

 fox : I suppose this animal preys on the mice and other 

 5mall rodents, which, as long as there is the least vege- 

 tation, subsist in considerable numbers in very desert places. 

 In Patagonia, even on the borders of the salinas, where a 

 drop of fresh water can never be found, excepting dew, 

 these little animals swarm. Next to lizards, mice appear 

 to be able to support existence on the smallest and driest 



