The Columbia river has entrenched itself in a canyon-like valley around the northern and Western side of the lava plains; Snake river has cut a deeper canyon farther south-east where the plains are higher and has disclosed the many lava sheets which build up the plains, occasionally revealing a buried mountain in which the superposed river has cut an even narrower canyon.
The Columbia river canoe resembled that of the Amur, the bow and stern being pointed at the water-line.
In the woods of Oregon, from the Columbia river southwards, an oak is found bearing some resemblance to the British oak in foliage and in its thick trunk and widely-spreading boughs, but the bark is white as in Q.
End of the Cache valley poured its waters into the Columbia river system.
The Columbia river separates it from Oregon from the mouth of that river to the point of the upper intersection with the 46th parallel of N.
West of the Columbia river the plain is broken by several monoclinal ridges rising 2000 to 3000 ft.
VANCOUVER, a city and the county-seat of Clarke county, Washington, U.S.A., on the Columbia river about loo m.
It rises on the western slope of the Cascades and enters the Columbia river about 100 m.
Agriculture and Stock-Raising.--Oregon has some of the most productive agricultural lands in the United States, but they are rather limited in extent, being confined for the most part to the valleys west of the Cascade Mountains and the counties bordering .on the Columbia river east of those mountains.
The Northern Pacific, the first of the transcontinental roads to touch the Pacific north of San Francisco, reaches Seattle with a wide sweep to the south, crossing the Columbia river about where it is entered by the Yakima and ascending the valley of the latter to the Cascade Mountains.