'* (Bttgineenng 



that the supply of aspens near the 

 waters of the Moraine Colony close to my 

 home was almost exhausted, I wondered whether 

 it would be possible for the beavers to procure 

 a sufficient supply downstream, or whether they 

 would deem it best to abandon this old colony 

 and migrate. 



Out on the plains, where cottonwoods were 

 scarce, the beavers first cut those close to the 

 colony, then harvested those upstream, sometimes 

 going a mile for them, then those downstream ; 

 but rarely were the latter brought more than a 

 quarter of a mile. If enemies did not keep down 

 the population of a colony so situated, it was only 

 a question of time until the scarcity of the food- 

 supply compelled the colonists to move either up 

 or down stream and start anew in a place where 

 food trees could be obtained. But not a move 

 until necessity drove them ! 



Not far from my home in the mountains the 



139 



