GEOLOGICAL FORCES AT WORK 199 



And the lines of tree trunks to-day, preparing for the 

 next constructive annexation of the lake, are so regular 

 that one's first thought is that this is the work of man. 

 But these are things that my sketches and photographs 

 will show better than words. 



When later we got onto the treeless Barrens or Tun- 

 dra, the process was equally evident, though at this 

 time dormant, and the chief agent was not running 

 water, but the giant Jack Frost. 



