In order to account in some measure for the diversity of soil observable in the vallies of most of our western rivers, it may not be improper in this place to assign one of the principal causes that operate in producing this effect. The alluvial deposits of which the river bottoms are formed, consist of particles of mud and sand, more or less minute. The coarser and more ponderous particles are of course soonest deposited, while the finer are transported by the current to a greater distance, and deposited near the mouths of the rivers. Thus it happens, that the bottoms situated nearest to the sources of the western rivers, are sandy, and contain but a small proportion of vegetable mould, while those nearer their mouths are generally furnished with a rich and fertile loam.
The Konzas, or Konzays, as it is pronounced by the Indians, is made up of two considerable streams, heading in the plains between the Platte and Arkansa rivers, called the Republican and Smoky-hill forks; tributary to the former of these, are the Solomon's and Salim forks, of less magnitude, rising also in the same plains. The Konzas is navigable only in high freshets for boats of burden, and on such occasions not more than one hundred and fifty or two hundred miles, the navigation being obstructed by shoals. {229} The character of this river and its several branches is similar to that of the Platte and its tributaries. Woodlands are seldom to be met with, except in narrow skirts and small copses along the watercourses. Much of the country situated upon its forks is said to be possessed of a good soil, but is rendered uninhabitable for want of timber and water. The bottoms are possessed of a light sandy soil, and the uplands are in many places characterized by aridity and barrenness. The surface for the most part is rolling, but in some instances inclines to hilly.
That portion of the Arkansa included within the section under consideration has a bed or channel varying in width from four hundred yards to more than a mile, exclusively of islands. In the neighbourhood of the mountains, its width does not exceed fifty or sixty yards, gradually growing wider in its progress downward. Its valley, for a distance of more than one hundred miles from the place where it issues from the mountains, contains a considerable timber-growth, principally of cotton-wood, in skirts bordering upon the river, which occasionally embosoms islands clad in the same kind of growth. Every appearance of timber, however, is lost on a further progress eastward, and nothing is presented to variegate or adorn the prospect inland, but a broad expanse of waving prairies.
Proceeding eastward along the river, its valley gradually widens, and the bluffs or banks by which it is bounded become less elevated and abrupt. The bottoms rise but a few feet above the water-level of the river, but the freshets, having a broad bed like that of the Platte to expand upon, seldom rise so high as to inundate the bottoms. This part of the Arkansa, as before hinted, cannot be considered as navigable, except for boats of light burden during the prevalence of a freshet. In a very low stage, the river is said to disappear in many places, the {230} whole of its water passing off through the immense body of sand of which its bed is composed.
The Arkansa, having a direction nearly east and west, has no great variety of climate to traverse in its course from the mountains to the Mississippi; consequently there is no succession of thaws taking place upon the river, calculated to maintain a freshet for any considerable length of time. The freshets are occasioned by a simultaneous melting of the snow throughout the whole extent of the river, and by showers of rain, which, falling upon a rolling surface, is quickly drained off, and causes sudden, but seldom excessive rises in the river. I have witnessed, in the Arkansa, no less than three considerable rises and falls of the water in the course of two weeks.
The most considerable streams tributary to this part of the Arkansa are the Negracka or Red Fork, and the Newsewketongu, or Grand Saline, on the south, and the Little Arkansa and Stinking Fork on the north side. The Negracka rises within fifty or sixty miles of the mountains, and after meandering eastwardly between four and five hundred miles, unites with the Arkansa at the distance of about nine hundred miles from the mouth of the latter. The Newsewketongu has its source in the plains between the Arkansa and Canadian rivers, and unites with the former about one hundred and fifty miles below the Negracka. The head waters of the Little Arkansa interlock with those of the Smoky-hill Fork of the Konzas, and are discharged into the Arkansa, about fifteen hundred miles above its mouth. The Stinking Fork rises amongst the head-waters of the Neosho, and enters the Arkansa about eight hundred miles from its mouth. Besides these, there are many other streams of smaller size entering on both sides of the river.
The Canadian rises at the base of the Rocky Mountains, and after a meandering course of about {231} one thousand miles, enters the Arkansa at the distance of about five hundred and fifty miles from the mouth of the latter. This river has generally been represented, upon the maps of the country, as having a north-easterly course; whereas its source is nearly in the same latitude as its confluence with the Arkansa, consequently its general course is nearly east. In its course, it forms an extensive curve to the southward, leaving a broad space between it and the Arkansa, in which several streams, many hundred miles in length, tributary to both of these rivers, have their origin and course.
This river has a broad valley, bounded by bluffs from two to five hundred feet high, faced with rocky precipices near its source, and presenting abrupt declivities, intersected by numerous ravines lower down. It has a spacious bed, depressed but a few feet below the bottoms, and exhibiting one continued stratum of sand through the greater part of its length. It is the channel through which the water of a vast extent of country is carried off, yet, during most of the summer season, it is entirely destitute of running water throughout a large proportion of its extent, a circumstance in proof of the aridity of region drained by it. Fifty miles above its mouth, it receives at least two-thirds of its water from its principal tributary, denominated the North Fork. This fork rises between the Arkansa and Canadian, and has a meandering course of about seven hundred miles. Six miles above the fork just mentioned, another tributary enters the Canadian called the South Fork, about half as large as the other. Notwithstanding the supplies afforded by these two tributaries, the Canadian has not a sufficiency of water in summer to render it navigable even to their mouths. At the distance of twenty miles above its mouth, a chain of rocks (slaty sandstone) extends across the bed of the river, but occasions no considerable fall. A little above the entrance of the South Fork, is another of the same {232} description, forming rapids of moderate descent, not more than four hundred yards in length. With these exceptions, the bed of the river presents no rocky formations in place, for more than four hundred miles from its confluence with the Arkansa. About three hundred and fifty miles from that point, beds of gypsum, or plaster of Paris, begin to make their appearance in the bluffs fronting upon the river, and upon the declivities of the highland knobs. A great abundance of this article is to be met with, not only upon the Canadian, but also upon the upper part of the Arkansa. The hills, in which it is imbedded, are composed of ferruginous clay and fine sand of a deep red complexion. Hence the Arkansa derives the colouring matter that gives to its waters their reddish hue.
The bottoms of the Canadian, in the neighbourhood of its mouth, are possessed of a soil exceedingly prolific; but, like those of the other rivers of this region, the more remote their situation from the mouth of the river, the more sandy and sterile is their appearance. Its valley is plentifully supplied with timber of an excellent quality, for a distance of about two hundred miles on the lower part of the river; and the high lands, for nearly the same distance, are agreeably diversified with prairies and woodlands. This portion of the river is situated eastward of the assumed meridian, and the country upon it has already been partially described in a former part of this report.
The woodland growth, upon the lower part of the Canadian, consists of cotton-wood, sycamore, white, blue, and black ash, swamp cedar, red elm, coffee tree, yellow wood, sugar tree, box elder, white and black walnut, wild cherry, mulberry, &c. in the river valley; and hickory, white and post oak, black jack, black oak, &c. upon the adjacent uplands. On a progress westward, the most valuable of the timber trees above enumerated disappear, till at length occasional groves of cotton-wood, mingled with mulberry, {233} red elm, and stunted shrubbery of various kinds, constitute the only woodlands of the country. On this occasion, it may be observed, that the cane or reed, the pea-vine, pawpaw, spice-wood, hop-vine, and several other varieties of shrubs and vines common only to rich soils, are no where to be found within this section, or westward of the proposed meridian.