1646 THE STORY OF THE UNIVERSE 



the water, so that it can not be closed up by ice during 

 the severe winters of these regions. 



Within, near the entry, the beavers form, with the 

 aid of a partition, a special compartment to serve as a 

 storehouse, and they there pile up enormous heaps of 

 nenuphar roots as provisions for the days when ice 

 and snow will prevent them from barking the young 

 trunks. 



A dwelling of this kind may last for three or four 

 years, and the animal here tranquilly enjoys the fruits 

 of its industry as long as man fails to discover the 

 retreat; for the beaver can escape by swimming from 

 all carnivorous animals excepting, perhaps, the 

 otter. During the floods the level of the water nearly 

 reaches the hut; if the inundation is prolonged and 

 the animal runs the risk of being asphyxiated beneath 

 his dome, it breaks through the upper part with its 

 teeth and escapes. When the water returns to its bed 

 the beaver comes back, makes the necessary repairs, 

 and resumes the usual peaceful course of its life. 



We have thus seen, from a shapeless hole to these 

 complex dwellings, every possible stage; we have 

 found among animals the rudiments of the different 

 human habitations, certain animals, indeed, having 

 arrived at a degree of civilization which man him- 

 self in some countries has not yet surpassed, or even 

 indeed yet attained. 



