Rocky Mountains, 119 



the river valley, that we were still above. He accordingly 

 retraced his course, until he discovered the smoke of our 

 encampment. He had been much harassed, in the night, by 

 mosquitots; and bisons having recently occupied the shade 

 of the tree under which he slept, the place afforded as little 

 refreshment for the horse as for himself. Delaying a little to 

 allow him time to make amends for his long abstinence, we 

 left our camp at a later hour than usual, and moving along 

 a wide and somewhat grassy plain, halted to dine near an 

 old Indian breast- work, by the side of a grove of cotton- 

 wood trees, intermixed with a few small-leaved elms. This 

 breast-work is built like that discovered on the Platte, a few 

 days march above the Pawnees. We have met with the re- 

 mains of similar works in almost every grove of trees about 

 the base of the mountains. Near some of them, we noticed 

 holes dug a few feet into the ground, probably as caches or 

 depositaries of provision, the earth which was raised having 

 been removed to a distance, or thrown into the river that 

 that it might not lead to the discovery of the concealed arti- 

 cles. We sometimes saw large excavations of this kind, 

 having an entrance comparatively small, and so placed as to 

 be easily concealed, made by white hunters, to hold their 

 furs, and whatever else they might wish to deposit in safe 

 keeping. 



The occurrence of the elm, the phytolacca, the cephalan- 

 thus, and other plants, not met with in a desert of sand, 

 gave us the pleasing assurance of a change we had long 

 been expecting in the aspect of the country. The blue 

 jay, the purple martin, a deer, and some turkies were 

 also seen near this encampment. The bed of the river is 

 here, eight hundred yards wide, but the quantity of water 

 visible is much less than in some places above. The mag- 

 netic variation, ascertained at this camp, was 12^ 30' east. 



