THE PERSISTENT BEAVER 59 
pile, and prevented the ice from troubling the 
colonists. Beavers apparently comprehend the 
advantage of having a house close to a spring. 
This spring commonly is between the main house 
entrance and the winter food-pile. 
Their pond did not fill with sediment. As 
the waters came entirely from springs they 
were almost free of sediment. After eighteen 
years of use there was but a thin covering of 
sediment on the bottom of the pond. Neither 
brook nor stream entered this pond. Was this 
pond constructed in this place for the purpose 
of avoiding sediment? As beavers occasion- 
ally and with much labour build in a place of 
this kind, when there are other and easier near- 
by places in which to build, it may be that this 
pond was placed here because it would escape 
sediment. This was the founding of the Spruce 
Tree colony. It is still inhabited. 
