The _Arkansas_ river penetrates far into the Rocky Mountains, its ramifications, interlocking with some of the waters of the Missouri, Columbia, San Buenaventura, Colorado of the West, and Rio del Norte.[155] The channel of this stream, in its course through the Prairies, is very wide and shallow, with banks in many places hardly five feet above low water. It will probably measure nearly 2000 miles in length, from its source to the frontier of Arkansas. It is called _Rio Napeste_ by the Mexicans; but among the early French voyagers it acquired the name of _Arkansas_, or rather {196} _Akansa_,[156] from a tribe of the Dahcotah or Osage stock, who lived near its mouth. This river has numerous tributaries, some of which are of great length, yet there is not one that is at all navigable, except the [Pg252] Neosho from the north, which has been descended by small boats for at least a hundred miles. _Red River_ is much shorter and narrower from the frontier westward than the Arkansas, bearing but little over half the volume of water. Even in its serpentine course it can hardly exceed 1200 miles from the Arkansas boundary to its source. This river rises in the table plains of the Llano Estacado, and has not, as I have been assured by traders and hunters, any mountainous elevations about its source of any consequence;[157] although we are continually hearing the inhabitants of its lower borders speak of the "_June freshets_ produced by the melting of the snow in the mountains." The upper portions of this river, and emphatically from the mouth of the False Washita (or Faux Ouachittâ) upward, present little or no facilities for navigation; being frequently spread out over sand-bars to the width of several hundred yards. A very credible Indian trader, who had been on Red River {197} some two hundred miles above the False Washita, informed me, that, while in some places he found it not over fifty yards wide, in others it was at least five hundred. This and most other prairie streams have commonly very low banks with remarkably shallow channels, which, during droughts, sometimes go dry in their transit through the sandy plains.[158] [Pg253] It would be neither interesting nor profitable to present to my readers a detailed account of all the tributaries of the three principal rivers already mentioned. They may be {198} found for the most part laid down, with their bearings and relative magnitudes, upon the map which accompanies this work. It is only necessary to say in addition, that none of them can ever be availed of to any considerable extent for purposes of navigation. With regard to the productions of the soil of these regions, the reader will probably have formed, in the main, a tolerably correct idea already; nevertheless a few further specifications may not be altogether unacceptable.