Travels in a Tree-top 39 



of the larger trees. There was at times no 

 well-defined channel, and often we could hear 

 the gurgling waters hurrying beneath our feet, 

 yet catch no glimpse of them. 



Here, too, other springs welled to the sur- 

 face, and the augmented volume of waters 

 finally left the swamp a stream of considerable 

 size, which, after a tortuous course through 

 many fields, entered a deep and narrow ravine. 

 After untold centuries the brook has worn 

 away the surface soil over which it originally 

 flowed, then the gravel beneath, and so down 

 to the clay, thirty feet below. Upon this 

 now rest the bowlders and such coarser mate- 

 rial as the waters could not transport. 



Clinging to the trees growing upon the 

 sides of the ravine, we closely followed the 

 course of the troubled, bubbling, foamy 

 waters, stopping ever and anon to look at 

 the exposed seftions of sand and gravel here 

 shown in curious alternate layers. The 

 meaning of the word " deposits," so fre- 

 quently met with in descriptive geology, 

 was made plain, and when we noticed of 

 how mixed a charafter was the coarse gravel, 

 it was easy to comprehend what had been 

 read of that most interesting phase of the 



