2. The second great division of Canada-the Interior Plains-comprises the area, some 700 miles in breadth, which continues the plains of the United States northward to the shores of the Arctic Sea, between Hudson Bay and the Rocky Mountains. This region is, however, more broken, well watered, and has more forest than the high, open plateaus southward, and is lower, constantly diminishing in altitude northward, the international boundary (lat. 49° N.) nearly coinciding with the watershed between the drainage into the Gulf of Mexico and that into Hudson Bay. Referring to this Canadian plains region, George M. Dawson, former director of the Geological Survey of Canada, wrote:

See NEW BRUNSWICK; NOVA SCOTIA; PRINCE Saskatchewan, on about the 55th parallel of EDWARD ISLAND. north latitude, a line of rocky and forested highlands forms a watershed between its valley and that of the outflow towards the north. This begins with the great Athabaska and Peace rivers, which pass eastward from the base of the Rockies through a rough region to Athabaska Lake, and thence enlarged (as the Slave River) to Great Slave Lake, which also receives the powerful Liard from the west. This lake narrows westwardly into the Mackenzie, which flows northwestward 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 discharges more water than does that stream, and is comparable to the mighty watercourses of Siberia. 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, halfway 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 Bay by way of the Coppermine River. East of the head of the Coppermine a low divide turns the waters east of it into the Great Fish or Backs River, which flows through the desolate wastes, called the Barren Grounds, that lie between Hudson Bay and the Arctic Ocean (Victoria Strait), and empties into the latter at Elliot Bay. Of all these rivers, the greatest is the Mackenzie, but the most important are the Saskatchewan and the Red, for they have made available a wide area of habitable and valuable land. The Saskatchewan collects a large part of the waters of the provinces of Alberta and Saskatchewan, by the two main channels, each some 300 miles in length, and then flows 200 miles more to Lake Winnipeg. This lake also receives, besides the Red River and its tributary, the Assiniboine (which drains all southern Manitoba and much of North Dakota and Minnesota), the Winnipeg River, and the lakes Manitoba, Dauphin, and Winnipegosis, which together equal or exceed the bulk of Lake Erie. Lake Winnipeg itself is nearly as spacious as Lake Huron, and pours its waters through the great Nelson River, a series of rapids descending to Hudson Bay. The Saskatchewan and Red rivers were the former avenues of travel, and their valleys are now the seat of the principal population and industry in the Northwest.

"The whole interior region of the continent slopes gradually eastward from the elevated plains lying near the base of the Rocky Mountains 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 fifty-fourth and forty-ninth degrees of latitude, however, along the lines which are in a general way parallel and hold a northwest and southeast course across the plains, very remarkable steplike rises occur. These escarpments form the eastern boundaries of the two higher prairie plateaus, and the most eastern of them overlooks the lowest prairie level, or that of the Red River valley. The three prairie steppes thus outlined differ much in age and character, and have been impressed on the soft formations of the plains by the action of subaërial denudation of former great 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 slope of the plains. The direction of greatest inclination is towards the northeast, and a line drawn from the intersection of the forty-ninth parallel 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 slope 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 extensive 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 Columbia."

Along the edge of the lowest or easternmost of these levels lies that series of great lakesManitoba, Winnipeg, Winnipegosis, Reindeer, La Hache, and many other lesser ones-which form 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, and Dubawnt, carrying to the northern part of Hudson Bay some overflow from Lake Athabaska; while from the foot of the Rocky Mountains, gathering the drainage of all 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-Assiniboine affluent), and thence to flow through Nelson River to Hudson Bay. North of the North

3. The mountainous western border of Canada consists of a belt of snowy ranges from 500 to 600 miles in width. On the east are the Rocky Mountains, continuous with those of Montana, which consist of gigantic uplifts and foldings of the strata. Hence the scenery presents series of vast bedded cliffs, and weatherworn, jagged summits, instead of the rounded domes and slopes familiar in the southern Rockies. The ranges run northwest in approximately parallel lines, which are capped with snow and glaciers. This is due to their high latitude rather than to altitude, since there are but few peaks that exceed 11,000 feet, except between lat. 52° and 53°, where a number of peaks have recently been described whose elevations appear to exceed 13,000 and 14,000 feet. Mounts Robson, Columbia, Forbes, Bryce, Alberta, and Freshfield are seemingly the highest. A somewhat distinctive range west of the first is the Selkirk, in which are the headwaters of the