On the 16th, we found the river narrowed; the banks rose on either side in elevations, without, however, offering a single tree.  We reached the river Wallawalla, which empties into the Columbia on the southeast.  It is narrow at its confluence, and is not navigable for any great distance.  A range of mountains was visible to the S.E., about fifty or sixty miles off.  Behind these mountains the country becomes again flat and sandy, and is inhabited by a tribe called the Snakes.  We found on the left bank of the Wallawalla, an encampment of Indians, consisting of about twenty lodges.  They sold us six dogs and eight horses, the greater part extremely lean.  We killed two of the horses immediately:  I mounted one of the six that remained; Mr. Ross took another; and we drove the other four before us.  Toward the decline of day we passed the river Lewis, called, in the language of the country, the Sha-ap-tin.  It comes from the S.E., and is the same that Lewis and Clarke descended in 1805.  The Sha-ap-tin appeared to me to have little depth, and to be about 300 yards wide, at its confluence.

The country through which we were now passing, was a mingling of hills, steep rocks, and valleys covered with wormwood; the stems of which shrub are nearly six inches thick, and might serve for fuel.  We killed six rattlesnakes on the 15th, and on the 16th saw a great many more among the rocks.  These dangerous reptiles appeared to be very numerous in this part of the country.  The plains are also inhabited by a little quadruped, only about eight or nine inches in length, and approaching the dog in form.  These animals have the hair, or poil, of a reddish brown, and strong fore-paws, armed with long claws which serve them to dig out their holes under the earth.  They have a great deal of curiosity:  as soon as they hear a noise they come out of their holes and bark.  They are not vicious, but, though easily tamed, can not be domesticated.

The natives of the upper Columbia, beginning at the falls, differ essentially in language, manners, and habits, from those of whom I have spoken in the preceding chapters.  They do not dwell in villages, like the latter, but are nomads, like the Tartars and the Arabs of the desert:  their women are more industrious, and the young girls more reserved and chaste than those of the populations lower down.  They do not go naked, but both sexes wear habits made of dressed deer-skin, which they take care to rub with chalk, to keep them clean and white.  They are almost always seen on horseback, and are in general good riders; they pursue the deer and penetrate even to Missouri, to kill buffalo, the flesh of which they dry, and bring it back on their horses, to make their principal food during the winter.  These expeditions are not free from danger; for they have a great deal to apprehend from the Black-feet, who are their enemies.  As this last tribe is powerful and ferocious,