BEAVER LODGES AND BURROWS. 



153 



for centuries by the simple process of repairing. Such 

 is doubtless their history. New lodges would be de- 

 manded with an increase in numbers up to a certain 

 limit, but otherwise they would not, in all probability, 

 be constructed. 



Around the outer rim of the chamber (Fig. 13) 

 there was fresh dry grass for beds, which had evidently 

 been recently cut from the meadows. In the centre 

 of the floor there was a large quantity of old and de- 

 cayed grass, damp and wet, on the removal of which 

 a considerable depression of the floor was observable. 



Fig. 13. 



Ground Plan of Lodge. 



The above diagram shows the chamber and the 

 position of the entrances. 



Measurements. 



Diameter of chamber parallel with canal 6 feet 5 inches. 



Transverse diameter 6 " 



Height of chamber at centre 1 foot Oinches. 



Level of floor below ground 6 " 



Height of floor above water in entrances -4 " 



For the purpose of ascertaining the nature of the 

 floor we made an excavation, 1 foot and 9 inches deep. 



