THE FRIENDLY ROCKS 



issued from the rocks a few yards away, and set 

 upon a little shelf as if it had grown there. There 

 was a hole on one side that led to the soft and warm 

 interior, but when my forefinger called, the tiny 

 aristocrat was not in. Whether he or she belonged 

 to the tribe of the white-footed mouse, or to that of 

 the jumping mouse, I could not tell. Was the de- 

 vice of the mossy exterior learned from the phoebe? 

 Of course not; both had been to the same great 

 school of Dame Nature. 



Through the eyes of the geologist I see what the 

 agents of erosion have done, how the tooth of time 

 has eaten out the layers of the soft old red sand- 

 stone, and left the harder layers of the superimposed 

 Catskill rock to project unsupported many feet. I 

 see these soft red layers running through under the 

 mountains from valley to valley, level as a floor, 

 and lending themselves to the formation of the beau- 

 tiful waterfalls that are found here and there in the 

 trout brooks of that region. At one such waterfall, 

 a mile or more from the old schoolhouse, we used to 

 go, when I was a boy, for our slate pencils, looking 

 for the softer green streaks in the crumbling slaty 

 sandstone, and trying them on our teeth to see 

 whether or not they were likely to scratch our pre- 

 cious slates. In imagination I follow this slaty layer 

 through under the mountains and see where it is cut 

 into by other waterfalls that I know, ten, twenty, 

 thirty miles away. At those falls the water usually 

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