Mineralogy and Geology of the White Mountains. 123 



furrowed and rounded for a great distance in a very remarkable 

 manner, into troughs bounded by large salient and re-entering 

 curves, and presenting also many subordinate basins of consider- 

 able size. 



The basin is of the same class with the pot-holes at the foot of 

 cataracts, and owing to similar causes ; but from the smallness of 

 the stream, and the nature of the rock, a remarkably hard and 

 compact granite, it is one of the most extraordinary cavities of 

 the kind that has been described. 



In beauty it may justly rival the Castalian fountain ', but as a 

 chronometer it is most interesting to the geologist. 



Science has not yet discovered, by experiment and observation, 

 the law of attrition of granite by running water ; and the stream 

 that flows here seems utterly inadequate to the production of the 

 effect within the historical period, and would seem to carry back 

 the antiquity of the world to a remote era. 



Granite Veins in Granite. 



These are very numerous, and on a large scale. There is a 

 remarkable one of this character, on the right hand of the road, 

 just north of the basin. The granite is fine grained, and dark, 

 with mica or hornblende. The vein, on the contrary, is feld- 



Fig. 6. 





