216 THE AMERICAN BEAVER. 



appear to be a series of alternating footholds sunk in 

 the bank by long use, rather than continuous depres- 

 sions in the form of a sunken trail. Their lines along 

 the bluffs can be seen as distinctly in the clear atmos- 

 phere of this region, for a quarter of a mile, as a chalk 

 line upon a black-board immediately before the eyes. 

 The preceding diagram, in two sections, is from a 

 rough sketch made while we were passing the bluffs at 

 the distance of a few hundred feet. It seems probable 

 that the mountain sheep resort to these precipitous 

 banks for safety as well as rest, since while upon their 

 dizzy declivities they could enjoy the consciousness of 

 perfect security.^ 



From this long digression I return once more to the 

 beaver, to make a brief reference to the connection of 

 the great river systems of North America with the 

 spread of this animal. The true habitat of the beaver 

 is near the sources of streams, where they are small 

 and easily spanned with dams. This transfers them 

 to the mountain and elevated areas as their appropf'- 

 ate home. And yet, as they are migrating animals, 



^ The least reputable animal of the Missouri is the gray wolf, 

 the largest of his genus in North America, and the most insatiable 

 of the carnivorous genera. They are very numerous, following 

 the buffalo in their migrations, and preying upon their young 

 as well as upon the wounded and decrepid. The ^wariness of 

 the wolf was well illustrated to us, one day, by his manner of 

 drinking. We saw one jump down the bank of the river, which 

 was about five feet high, upon a piece of fallen earth just above 

 the water, and lap the water for about five seconds, and then jump 

 up again upon the bank to see whether anyone was approaching. 

 After this he returned and drank again for the same length of 

 time, and again ascended the bank to repeat his observation. 

 These proceedings were repeated six or eight times before his 

 thirst was satisfied. 



