UNITED STATES. 499 



in latitude 46. From this point the distance to the Mississippi is 

 less than from the Platte. From the northernmost part of the great 

 bend, above the Mandans, and in latitude 47° we ascend nearly west; 

 the course of the three forks, Jefferson, Madison, and Gallatin, is 

 nearly south-west and south. The current of this river is at least 

 a fourth greater than that of the Mississippi. To the Platte, it is 

 amazingly swift, and stemmed with great difficulty, abounding with 

 shoals and sand bars, sawyers, rafts projecting from the shore, and 

 islands. It is almost impracticable to descend in flat-bottomed boats, 

 even in the highest stages of the water : in barges great care and 

 dexterity are requisite. Above the Platte, the Missouri, though not 

 less swift in current, is rendered more easy of navigation by the 

 large sand bars, and clear banks, which admit of towing. To the 

 falls, two thousand miles further, it preserves the same character; 

 the navigation however becomes less dangerous, or difficult, except- 

 ing from the shoals, which in low water are abundant. Above the 

 falls or cataracts, there is a clear fine river five hundred miles to 

 the three forks, affording better navigation than any part of the 

 Missouri, although the channel is generally narrow and sometimes 

 confined between lofty mountains. The three forks are all fine rivers, 

 and receive a great number of smaller streams. The Missouri re- 

 ceives all its principal rivers from the south-west side. 



The floods of this river usually begin early in March, and there is a 

 continued succession of them until the last of July ; the river subsiding 

 and again rising as the different rivers bring down their annual tributes. 

 There is little variation in its width from its mouth to the cataracts. 

 In some places it spreads considerably, and in these, sandbars im- 

 pede the navigation in low water: at these times the river is reduced 

 in places to less than a fourth of its usual breadth, between sand- 

 bars which advance into it, and a high bank. But when the channel 

 is full, the river even at the Mandans appears not less broad or ma- 

 jestic than does the Mississippi at New Orleans. The cataracts of 

 the Missouri, from every description, are, next to those of Niagara, 

 the most stupendous in the world. The descent, in the distance of 

 eighteen miles, according to the estimation of Lewis and Clark, is 

 362 feet 9 inches. 



The first great pitch 98 feet 



— second . 19 — 



— third . 47 — 8 inches 



— fourth . 26 — 



besides a number of smaller ones. The width of the river is about 

 three hundred and fifty yards. The whole extent of navigation of 

 this river which has no other cataract or considerable impediment, 

 from the highest point on Jefferson river, the largest of the three 

 forks, to its entrance into the Mississippi, is three thousand and 

 ninety-six miles ; no other tributary stream in the world possesses 

 such a navigation. 



The Arkansas, next to the Missouri, is the most considerable tri- 

 butary of the Mississippi. In length it is nearly two thousand five 

 hundred miles, and navigable at proper seasons nearly the whole dis- 

 tance. In many places its channel is broad and shallow, at least 

 above the rapids, so as to render navigation almost impracticable. 

 Until eight or nine hundred miles from its mouth, it receives no 



