RUNNING WATEKS 



167 



some heaviness of movement but higher up 

 in the hills it is all rush, vivacity, and sparkle. 

 It chatters and gurgles and swishes and swirls 

 all day long, working its way in and out, over 

 and under bed bowlders, waterfalls, and deep 

 pools. Where it runs through meadow or low- 

 land, it keeps changing and moving its banks 

 continually. Like the larger stream, the swing 

 in of the water toward the shore hollows out a 

 pool or deep eddy, and the sand removed from 

 that bank is always deposited a few yards below 

 and on the opposite bank, where a bar is form- 

 ing. 



This shift of bed is not so noticeable farther 

 up in the hills, where the brook runs between 

 shores of rock. The change in the confining 

 banks is slight, but now there is wear of an- 

 other sort. The waterfall keeps cutting back 

 into the rock, the pool or basin beneath the 

 fall keeps deepening, the bed along which sand 

 and stones are hurried keeps sinking, and the 

 vegetation year by year creeps lower down to 

 cover the bare shores left by the receding water. 

 The erosion of the brook tends toward deepen- 

 ing the ravine and producing what is called 

 Ihe gorge or the glen. The wear here is, in 

 proportion, the wear of the whole basin from 



The mot 

 tain- 

 stream. 



In the 

 ravine. 



