336 CHARLES DARWIN 



geologist; the thousands and thousands of stones, which, 

 striking against each other, made the one dull uniform sound, 

 were all hurrying in one direction. It was like thinking on 

 time, where the minute that now glides past is irrevocable. 

 So was it with these stones ; the ocean is their eternity, and 

 each note of that wild music told of one more step towards 

 their destiny. 



It is not possible for the mind to comprehend, except by 

 a slow process, any effect which is produced by a cause re- 

 peated so often, that the multiplier itself conveys an idea, 

 not more definite than the savage implies when he points to 

 the hairs of his head. As often as I have seen beds of mud, 

 sand, and shingle, accumulated to the thickness of many 

 thousand feet, I have felt inclined to exclaim that causes, 

 such as the present rivers and the present beaches, could 

 never have ground down and produced such masses. But, on 

 the other hand, when listening to the rattling noise of these 

 torrents, and calling to mind that whole races of animals have 

 passed away from the face of the earth, and that during this 

 whole period, night and day, these stones have gone rattling 

 onwards in their course, I have thought to myself, can any 

 mountains, any continent, withstand such waste? 



In this part of the valley, the mountains on each side were 

 from 3000 to 6000 or 8000 feet high, with rounded outlines 

 and steep bare flanks. The general colour of the rock was 

 dullish purple, and the stratification very distinct. If the 

 scenery was not beautiful, it was remarkable and grand. We 

 met during the day several herds of cattle, which men were 

 driving down from the higher valleys in the Cordillera. This 

 sign of the approaching winter hurried our steps, more than 

 was convenient for geologizing. The house where we slept 

 was situated at the foot of a mountain, on the summit of 

 which are the mines of S. Pedro de Nolasko. Sir F. Head 

 marvels how mines have been discovered in such extraordi- 

 nary situations, as the bleak summit of the mountain of S. 

 Pedro de Nolasko. In the first place, metallic veins in this 

 country are generally harder than the surrounding strata: 

 hence, during the gradual wear of the hills, they project 

 above the surface of the ground. Secondly, almost every 

 labourer, especially in the northern parts of Chile, under- 



