Page:The New International Encyclopædia 1st ed. v. 04.djvu/132

* CANADA. 106 CANADA. it is better defined the 'Laureutian Hills, which divides the heads of the streams flowing north- wird from those draining southward into the Saint Lawrence. This very ancient river valley, which includes the whole system of the Great Lakes (partly within the United States), is over •>000 miles long, and forms the drainage outlet for an area of about .500,000 square miles, ihe surface of the Saint Lawrence Valley is broken in places bv intrusive igneous rocks, which re- main standing above the surface in such abrupt hei-'hts as .Mount Roval, at Montreal, and the picturesque bultes south of that city. Another topographic feature in this region is the Niagara K-carpment, the eastern edge of a plateau over the brink of which the waters of Lake Erie are poured into Niagara Falls (q.v.). As the escarp- ment is traced northward, it becomes more lotty, risin" into high, rockv hills, which form the backbone of the triangular, very picturesque ex- tension of land separating Lake Huron from Georo-ian Bay. The valley of the Saint Lawrence narrows toward its mouth, where the northeast- ern extension of the Appalachians forms the mountainous Gaspe Peninsula and also the islands of Antieosti and Newfoundland. Soutn of this lies the distinct region of the JLaritime Provinces, whose features are largely similar to those of New England. See New BRDNSW^CIi; Nova Scotia; Prince Edw.rd Island. II The second great division of Canada — the Interior Plains— comprises the area, some 700 miles in breadth, which continues the plains ot the United States northward to the shores of the Arctic Sea, between Hudson Bay and the Rocky Mountains. This region is, however, more brok- en well watered, and has more forest than the high open plateaus southward, and is lower, eonstantlv diminishing in altitude northward ♦he inteiTiational boundary (latitude 49 iN.) nearly coinciding with the watershed between the drainage into the Gulf of Mexico and that into HudsoS Bav. Referring to this Canadian plains region, George M. Dawson, chief of the Geo- logical Survey of Canada, wrote: ''•The whole interior region of the continent slopes gradually eastward from the elevated plains lying near the base of the Rocky Moun- tains to the foot of the Laurentian Highlands, and though the inclination is more abrupt in approaching the mountains, it is not so much so as to attract special attention. Between the fiftv-fourth ami fortv-ninth degrees of latitude, however, along the lines which are in a genera! way parallel and hold a northwest and southeast course across the plains, very remarkable step- like rises occur. These escarpments form the easU-rn boundaries of the two higher prairie pla- teaus and the most eastern of them overlooks the lowest prairie level, or that of the Red River Valley. The three prairie steppes thus outlined <liirer much in age and character, and have been impressed on the soft formations ot the plains bv the action of suliaerial denudation of former .rieat lakes and probably also of the sea. ■ • ■ The actual increase of elevation accounted for in the two escarpments. However, is slight compared with that due to the uniform eastward sloi)e of the plains. The direction of greatest inclina- tion is toward the northeast, and a line drawn from the intersection of the forty-ninth iiarallel and the mountains to a point on the first prairie level north of Lake Winnipeg will be found to cross the escarpments nearly at right angles, and to have an average sU)pe of 5.38 feet to the mile. From the same initial point, in a due east line to the lowest part of the valley of the Red River, a distance of 750 miles, the plains have an average slope of 4.48 feet per mile. . . . Northwest of the North Saskatchewan no ex- tensive treeless plains occur in the central region of the continent, and the forest country of the east forms a wide, unbroken connection with that of the northern portion of British Co- lumbia." Along the edge of the lowest or easternmost of these levels lies that series of great lakes- Manitoba, Winnipeg, Winnipegoosis, Reindeer, La Hache, and nuuiy other lesser ones — which foiTii so striking a feature on the map, and empty by large, rapid rivers into Hudson Bay. Down from lakes on the second level flow such large rivers as the English or Churchill, Ice and Dobaunt, the Ice carrying to Hudson Bay some overflow from Lake Athabasca; while from the foot of the Rockv Mountains, and gathering the drain- age of ail three plains levels, comes the great Saskatchewan, in two branches, the North and the South, to enter Lake Winnipeg (which also receives from the south the large Red-Assini- boine affluent), and thence to flow through Nel- son River to Hudson Bay. North of the North Saskatchewan, on about the 53th parallel of north latitude, a line of rocky and forested highlands forms a Watershed between its valley and that ot the outflow toward the north. This begins with the great Athabasca and Peace rivers, which pass eastward from the base of the Rockies through a rough region to .Vthabasca Lake, and Ihence enlarged (as the Slave River) to Great Slave Lal<e, which also receives the powerful Liard from the west. This lake narrows west- wardlv into the Mackenzie, which flows nortli- westw'ard to the Arctic Ocean, about 120 miles east of the border of Alaska. This great river is the equal of the Missouri in length, but dis- charges more water than does that stream, and is comparable to the mighty watercourses of Si- beria. Its course lies near the base of the Rocky Mountains, west of which lie the head streams of the Yukon (q.v.). all of which are within Canadian territory. East of the Mackenzie, half way between Great Slave Lake and the Arctic Coast lies the extensive Great Bear Lake, a feeder for the Mackenzie. Here the country is low and a part of this lake's waters escapes into Coronation Bav by way of the CoiM'O-mhie Riv- er East of tile head of the Coppermine a low divide turns the waters east of it into the Great Fish or Back River, which flows through the desolate wastes, called the Barren (Jroun.ls. that lie between Hudson Bay and the Arctic Ocean (Victoria Strait), and empties into the latter at Elliot Bay. Of all the.se rivers, the greatest is the Mackenzie, but the most imiiortant are the Saskatchewan and the Re<l, for they have made available a wide area of habitable and valuable land The Saskatchewan collects most of the waters of the three districts. Alberta, .ssini- boine, and Saskatchewan, by the two main chan- nels, each some :iOO miles in length, and then flows 200 miles more to Lake Winnipeg. This lake also receives, besides the lied River and its tributary, the .ssiniboine (which drain all south- ern Manitoba and much of North Dakota and