that, considering their intimate relation to the general interest of commerce, seem to demand our first attention. The Columbia and its branches water almost the entire territory, and open a highway from the ocean to the lofty mountain ranges which form its eastern boundary. This river heads in lat. 52° north, long. 119° west from Greenwich, and, after pursuing a serpentine course for fifteen hundred or two thousand miles, finds its discharge in the Pacific, at lat. 46° north.
One hundred and twenty miles of this distance are navigable for ships of the largest class, but the remainder of its course is interrupted by occasional rapids and falls, that render frequent portages necessary.
The upper and lower "dalls" and "cascades," present the most serious impediments to navigation. The former of these, situated above Clarke's Fork, are caused by the passage of the Columbia through immense ledges, that leave
48 The treaty now in process of negotiation with Great Britain, relinquishes to that government all above the 49th deg., and consequently admits its claims to the entire northern boundary, to wit: from 49° to the Russian possessions.
huge vertical walls of basaltic rock upon either side, and compress its waters to a narrow, chasm-like channel. There, dashing and foaming in wild fury, the torrent rushes past its lateral dikes with frightful velocity.
The distance between these two "dalls" is some thirty miles.
The "cascades" lie at the base of a mountain range of the same name, one hundred and fifty miles from the Ocean. Near this place the whole stream is plunged over a precipice of fifty feet descent, forming a sublime and magnificent spectacle.
Between the dalls and cascades, a reach of high-lands, formed almost entirely of naked basalt, presents another barrier, through which the river forces itself by a tunnel-like pass for ten or fifteen miles, leaving vast mural piles upon the right and left, that attain an altitude of three hundred and fifty or four hundred feet.
A few miles above the junction of the southern and middle forks of the Columbia, two considerable lakes have been formed by the compressure of its waters among the adjoining mountains.
The first of these is about twenty miles long and six broad, shut in by high, towering hills, covered with stately pine forests.
Emerging from this, the river urges its way through lofty embankments of volcanic rock for some five miles or more, when a second lake is formed in a similar manner, which is about twenty-five miles in length and six in width.
NOTE.— Capt. Fremont, in speaking of the Columbia, makes use of the following just observations:
"The Columbia is the only river which traverses the whole breadth of the country, breaking through all the ranges, and entering into the sea. Drawing its waters from a section of ten degrees of latitude in the Rocky Mountains, which are collected into one stream by three main forks (Lewis', Clarke's, and the North Fork) near the centre of the Oregon valley, this great river thence proceeds by a single channel into the sea, while its three forks lead each to a pass in the mountains, which opens the way into the interior of the continent.
“This fact, in reference to the rivers of this region, gives an immense value to the Columbia. Its mouth is the only inlet and outlet to and from the sea; its three forks lead to passes in the mountains; it is, therefore, the only line of communication between the Pacific and the interior of North America; and all operations of war or commerce, of national or social intercourse, must be conducted upon it."
