The Nortitern seetioa of the Rocky Mountains extends from 49° N. let to the Arctic Ocean west of the mouth of the river Mackenzie, a distance of about 2000 miles, and is described generally under AMERICA and 110Dswes BAY TERRITORIES. The direction of the Rocky Mountains hero is nearly duo north-weaL The southern portion, between 49' and 55' N. lat., seems to be the highest part of the whole range. Moat of the summits are covered with snow all the year round. Mount Hooper is 15,690 feet and Mount Brown nearly 16,000 feet high ; thew two summits aro between 52° and 53° N. lat. On their eastern declivities rise the northern fork of the Saskatehevan and the river Athabasca, and from the western descend the rivers that form the northern fork of the Oregon River. There are two pawns over this portion of the Rocky Mouutoins: the more southern is near 52' 30' N. lat. ; the northern occurs near 53° 30' N. lat., between the Red Deer River, a branch of the Athabasca, and the northern branch of the Columbia River; hut these peases are only practicable from the end of June to the mid ile of September, when they aro crossed by the agents of the Hudson's Bay Company, who bring tho furs collected in the countries west of the Rocky Mountains to their establishments on the east of that range.
Farther north, between 56° and 57' N. lat., the Peace River breaks through the eastern range of the mountains, its upper course being in a valley between the two principal ranges, which appear to be here of nearly equal height : both of them contain summits which are always covered with snow; their height above the sea-level however seems to fall short of 5000 feet. The western range, which is about 200 iniles from the Pacific, constitutes the watershed between the rivers which run east to the Atlantic and west to the Pacific. North of 57° N. lat the mountains appear rather to sink lower than to rise. As far north as 62' N. lat. they seem to occupy a much greater width, and consist of three or more nearly parallel ranges, and the watershed between the rivers which fall respectively into the Atlantic and Pacific is advanced much more to the west. The Turnagain River, which after having left the mountain region caesuraes the name of the Southern Branch of the Mackenzie, rises on this watershed, and breaks through two ranges of mountains before it reaches the great plain east of the Rocky Ileeetaiss. Between the ranges which fill up this immense tract of eonatry there are low tract., which however are partly covered with water. It is said that about one-sixth of the entire surface of this region eonaists of extensive lakes.
Between 61' and 49* N. Lot, the eastern ranges of the Rocky Moun tains approach the valley of the Mackenzie River. Dr. Richardson says that they appear to consist of abort conical peaks, scarcely rising .000 fret above the river. Lateral ridges project from their sides, which stretch youth-south-west and north-northeast, being nearly at right angles to the general course of the great range, to which they belong. Their bases are from one to two mile. wide, and their
eastern slopes present a succession of (rrecipices, with shelving accli vities beneath them, formed of doibru, and exhibit on their faces regular lines of stratification. The valleys which separate these ridges and open upon the river, are narrow, with level bottoms, but very steep sides well clothed with trees. Oue of these ridges presents towards the river a very precipitous d-sce_nt, 1200 feet high, which extends for at least 15 miles. A large portion of this mountain region Is drained by the Peel River, which breaks through the eastern ridge near 67' 40' N. let.; at its junction with the Mackenzie River the Peel is of considerable size, and brings down a great volume of water.
The most northern portion of the Rocky Mountain system to its termination on the shores of the Arctic, Ocean consists of several parallel ridges. Between the embouchure of the most western arm of the Mackenzie River (137' W. long.) and 146' W. long., four distinct ridges are seen from 12 to 25 miles from the shore. At their northern extremity they are separated by valleys about 20 or 30 miles wide. The summits of the two eastern chains, called Richardson Chain and Buckland Chain, are lower, being free from snow in summer, but the two western, called British Chain and Romanzow Chain, are always covered with mow. Romanzow Chain occupies the greatest width, and presents to the Arctic Ocean a front exceeding GO miles in extent. These chains consist of elate-rocks; their summits are rounded and naked, but the narrow valleys between them are covered with grass. No bushes nor even shrubs appear on their declivities. At a great distance farther west, between 151' and 152°, the northern extremity of another chain, called the Pelly Mountains, is seen from the aborts of the Arctic, Ocean. It is most probable that the mountain-chain which is observed to skirt the shores of the Pacific, at no great distance from the sea, and in numerous places to advance with its offsets close to the water's edge, forma a part of the Rocky Mountain system and is connected with it. But on this point we are without information, the interior of the countries along this coast not having been explored by Europeans.
(Humboldt, Luta Politigue sup la Nouvelle Espagne ; Pike, Explora tory Travels through the Western Territory of North America, fin.; James, Account of Major Long's Expedition to the Rocky Mountains ; Lewis and Clarke, Travels to the Source of the Missouri, etc.; Mackenzie, reran through the Continent of North America to the Frozen and Pacific Oceans ; Franklin, Second Expedition to the Polar Sca ; Dense and Simpson ; Fremont ; Buxton, &c.)