THE BEAVER AND HIS WORKS. 



17 



feet, but the two ends, more than two thirds of the whole, are but 

 natural embankments artfully rendered subservient to the purpose of 

 the beaver by filling in between. 



Fig. 2.— Bbavbb Dam. 



It is these dams that produce those fine tracts of wild grass known 

 as beaver-meadows, upon which cattle and deer so love to feed, and 

 which so frequently furnish the pioneer with the means of subsistence 

 for his stock until he can prepare meadows of his own. Wherever a 

 brook trickled through a wooded valley, there the beaver made his 

 home. Large areas became inundated, the drowned trees fell and de- 

 cayed, and the freshets brought down new soil from the surrounding 

 hills and ridges. At length the pond filled up and forced the beaver 

 to migrate ; the dam unrepaired gradually became shaky and the 

 waters drained off, exposing a rich alluvial soil upon which sprang up 

 waving fields of wild grass. In due time a second growth of timber 

 appeared, and what was once a pond and valley became only a forest 

 bordered by low ridges. In the suburbs of the city of Port Huron, 

 Michigan, may be traced the remains of such a dam, of unknown age 

 and stupendous length. Serpentine in windings, its face may be fol- 



VOL. XXV. — 2 



