perfectly navigable.  There is a very large and plain Indian road leading up it, but it has at present no tracks, except those of horses which seem to have used it last spring.  The river here made a great bend to the southeast, and he therefore directed his course, as well as he could, to the spot where he had directed Chaboneau and Gass to repair, and struck the river about three miles above their camp.  It was now dark, and he, therefore, was obliged to make his way through the thick brush of the pulpy-leafed thorn and the prickly pear, for two hours before he reached their camp.  Here he was fortunate enough to find the remains of some meat, which was his only food during the march of twenty-five miles to-day.  He had seen no game of any sort except a few antelopes who were very shy.  The soil of the plains is a meagre clay, of a light yellow colour, intermixed with a large proportion of gravel, and producing nothing but twisted or bearded grass, sedge and prickly pears.  The drier parts of the low grounds are also more indifferent in point of soil than those further down the river, and although they have but little grass, are covered with southern wood, pulpy-leafed thorn, and prickly pears, while the moist parts are fertile, and supplied with fine grass and sandrushes.

We passed within the first four and a quarter miles three small islands, and the same number of bad rapids.  At the distance of three quarters of a mile is another rapid of difficult passage:  three miles and three quarters beyond this are the forks of the river, in reaching which we had two islands and several bayous on different sides to pass.  Here we had come nine miles and a quarter.  The river was straighter and more rapid than yesterday, the labour of the navigation proportionally increased, and we therefore proceeded very slowly, as the feet of several of the men were swollen, and all were languid with fatigue.  We arrived at the forks about four o’clock, but unluckily captain Lewis’s note had been left on a green pole which the beaver had cut down and carried off with the note, an accident which deprived us of all information as to the character of the two branches of the river.  Observing therefore that the northwest fork was most in our direction, and contained as much water as the other, we ascended it; we found it extremely rapid, and its waters were scattered in such a manner, that for a quarter of a mile we were forced to cut a passage through the willowbrush that leaned over the little channels and united at the top.  After going up it for a mile we encamped on an island which had been overflowed, and was still so wet that we were compelled to make beds of brush to keep ourselves out of the mud.  Our provision consisted of two deer which had been killed in the morning.