464 Expedition to the 



within the mountains, called the Bull-pen. This basin is sur- 

 rounded by high and rugged mountains, except at the place 

 where the North fork passes into the plains. On each side of 

 this strait, or pass, are high and abrupt rocky promontories, 

 which confine the river to a narrow channel. The diameter 

 of the circumscribed valley, called the Bull-pen, is one day's 

 travel, about twenty miles. The upper branches of the North 

 fork have some timber, mostly cotton-wood and willow, and 

 abound in beaver-* 



* Castor fiber. Some of the European naturalists appear to be in doubt, 

 whether or not, those of Europe are of the same species with ours, from 

 the circumstance of the former not erecting habitations for themselves, 

 thus appearing- to differ at least in habit, from the North American ones, 

 (which are usually but improperly called, Canada beaver, as they are not 

 confined to Canada, but are found far south in the United States, and east 

 to the confluence of the Ohio and Mississippi,) but it is possible, that the 

 aboriginal manners of the European beavers, corresponded with those of 

 ours, and that necessity, resulting from the population of the country by 

 civilized man, compelled them to resort to a different mode of life, to es- 

 cape the certain destruction, with which the great demand for their fur, 

 threatened them. But as the European beaver is smaller than ours, 

 other naturalists have regarded it as a distinct species. In those districts 

 of country of North America, from which they have not yet been exter- 

 minated, and which are populated by the whites, as particularly on the 

 Mississippi, above the Ohio, and below St. Louis, we have not heard that 

 they build, but it is more than probable, that, as in Europe, they change 

 their mode of life, in order to be the more effectually concealed from 

 view. From subsequent observation, we have learned, that the beaver 

 does not attempt to dam large streams, perceiving at once the impracti- 

 cability of the undertaking; his object in damming a stream appears to be, 

 to preserve a constancy in the height of the water, in order that the en- 

 trance to his habitation in the bank may be concealed, and that the 

 curious conical edifice, may not be destroyed by a sudden flood, or too 

 much exposed by a deficiency of water. 



An Indian informed us, that in his time, he has caught three specimens 

 of this animal, that had each a large white spot on the breast. Singular 

 accounts of this animal are given us by the hunters, but which we had no 

 opportunity of verifying. 



Three Beavers were seen cutting down a large cotton wood tree: when 

 they had made considerable progress, one of them retired to a short dis- 

 tance, and took his station in the water, looking steadfastly at the top of 

 the tree. As soon as he perceived the top begin to move towards its fall, 

 he gave notice of the danger to his companions, who were still at work, 

 gnawing at its base, by slapping his tail upon the surface of the water, and 

 they immediately ran from the tree, out of harm's way. 



The spring beaver are much better for commerce, than those of the 

 autumn and early winter, as the fur is loDger and more dense. But the 



