Sunday 18.  In order to relieve the men of captain Clarke’s party from the heavy weight of their arms provisions and tools, we exposed a few articles to barter for horses, and soon obtained three very good ones, in exchange for which we gave a uniform coat, a pair of leggings, a few handkerchiefs, three knifes and some other small articles, the whole of which did not in the United States cost more than twenty dollars:  a fourth was purchased by the men for an old checkered shirt, a pair of old leggings and a knife.  The Indians seemed to be quite as well pleased as ourselves at the bargains they had made.  We now found that the two inferior chiefs were somewhat displeased at not having received a present equal to that given to the great chief, who appeared in a dress so much finer than their own.  To allay their discontent, we bestowed on them two old coats, and promised them that if they were active in assisting us across the mountains they should have an additional present.  This treatment completely reconciled them, and the whole Indian party, except two men and two women, set out in perfect good humour to return home with captain Clarke.  After going fifteen miles through a wide level valley with no wood but willows and shrubs, he encamped in the Shoshonee cove near a narrow pass where the highlands approach within two hundred yards of each other, and the river is only ten yards wide.  The Indians went on further, except the three chiefs and two young men, who assisted in eating two deer brought in by the hunters.  After their departure every thing was prepared for the transportation of the baggage, which was now exposed to the air and dried.  Our game was one deer and a beaver, and we saw an abundance of trout in the river for which we fixed a net in the evening.

We have now reached the extreme navigable point of the Missouri, which our observation places in latitude 43 degrees 30’ 43” north.  It is difficult to comprise in any general description the characteristics of a river so extensive, and fed by so many streams which have their sources in a great variety of soils and climates.  But the Missouri is still sufficiently powerful to give to all its waters something of a common character, which is of course decided by the nature of the country through which it passes.  The bed of the river is chiefly composed of a blue mud from which the water itself derives a deep tinge.  From its junction here to the place near which it leaves the mountains, its course is embarrassed by rapids and rocks which the hills on each side have thrown into its channel.  From that place, its current, with the exception of the falls, is not difficult of navigation, nor is there much variation in its appearance till the mouth of the Platte.  That powerful river throws out vast quantities of coarse sand which contribute to give a new face to the Missouri, which is now much more impeded by islands.  The sand, as it is drifted down, adheres in time to some of the projecting points