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 shorter and smaller, owing to the encroachments of Peace and Liard rivers, tributaries of the Nelson, on the Cordilleran territory. All of these rivers are waterways of some importance in their lower course, and are navigated by powerful stern-wheel boats supplying the posts and mining camps of the interior with their requirements. In most cases they reach the coast through deep valleys or profound canyons, and the transcontinental railways find their way beside them, the Canadian Pacific following at first tributaries of the Columbia near its great bend, and afterwards Thompson river and the Fraser; while the Grand Trunk Pacific makes use of the valley of the Skeena and its tributaries. The divide between the rivers flowing west and those flowing east and north is very sharp in the southern Rocky Mountains, but there are two lakes, the Committee’s Punch Bowl and Fortress Lake, right astride of it, sending their waters both east and west; and there is a mountain somewhat south of Fortress Lake whose melting snows drain in three directions into tributaries of the Columbia, the Saskatchewan and the Athabasca, so that they are distributed between the Pacific, the Atlantic (Hudson Bay) and the Arctic Oceans. The divide between the St Lawrence and Hudson Bay in eastern Canada also presents one or two lakes draining each way, but in a much less striking position, since the water-parting is flat and boggy instead of being a lofty range of mountains. The rivers of Canada, except the St Lawrence, are losing their importance as means of communication from year to year, as railways spread over the interior and cross the mountains to the Pacific; but from the point of view of the physical geographer there are few things more remarkable than the intricate and comprehensive way in which they drain the country. As most of the Canadian rivers have waterfalls on their course, they must become of more and more importance as sources of power. The St Lawrence system, for instance, generates many thousand horse-power at Sault Ste Marie, Niagara and the Lachine rapids. All the larger cities of Canada make use of water power in this way, and many new enterprises of the kind are projected in eastern Canada; but the thousands of feet of fall of the rivers in the Rocky Mountain region are still almost untouched, though they will some day find use in manufactures like those of Switzerland.

The Archean Protaxis.—The broad geological and geographical relationships of the country have already been outlined, but the more important sub-divisions may now be taken up with more detail, and for that purpose five areas may be distinguished, much the largest being the Archean protaxis, covering about 2,000,000 sq. m. It includes Labrador, Ungava and most of Quebec on the east, northern Ontario on the south; and the western boundary runs from Lake-of-the-Woods north-west to the Arctic Ocean near the mouth of Mackenzie river. The southern parts of the Arctic islands, especially Banksland, belong to it also. This vast area, shaped like a broad-limbed V or U, with Hudson Bay in the centre, is made up chiefly of monotonous and barren Laurentian gneiss and granite; but scattered through it are important stretches of Keewatin and Huronian rocks intricately folded as synclines in the gneiss, as suggested earlier, the bases of ancient mountain ranges. The Keewatin and Huronian, consisting of greenstones, schists and more or less metamorphosed sedimentary rocks, are of special interest for their ore deposits, which include most of the important metals, particularly iron, nickel, copper and silver. The southern portion of the protaxis is now being opened up by railways, but the far greater northern part is known only along the lakes and rivers which are navigable by canoe. Though once consisting of great mountain ranges there are now no lofty elevations in the region except along the Atlantic border in Labrador, where summits of the Nachvak Mountains are said to reach 6000 ft. or more. In every other part the surface is hilly or mammilated, the harder rocks, such as granite or greenstone, rising as rounded knobs, or in the case of schists forming narrow ridges, while the softer parts form valleys generally floored with lakes. From the summit of any of the higher hills one sees that the region is really a somewhat dissected plain, for all the hills rise to about the same level with a uniform skyline at the horizon. The Archean protaxis is sometimes spoken of as a plateau, but probably half of it falls below 1000 ft. The lowland part includes from 100 to 500 m. all round the shore of Hudson Bay, and extends south-west to the edge of the Palaeozoic rocks on Lake Winnipeg. Outwards from the bay the level rises slowly to an average of about 1500 ft., but seldom reaches 2000 ft. except at a few points near Lake Superior and on the eastern coast of Labrador. In most parts the Laurentian hills are bare roches moutonnées scoured by the glaciers of the Ice Age, but a broad band of clay land extends across northern Quebec and Ontario just north of the divide. The edges of the protaxis are in general its highest parts, and the rivers flowing outwards often have a descent of several hundred feet in a few miles towards the Great Lakes, the St Lawrence or the Atlantic, and in some cases they have cut back deep gorges or canyons into the tableland. The waterfalls are utilized at a few points to work up into wood pulp the forests of spruce which cover much of Labrador, Quebec and Ontario. Most of the pine that formerly grew on the Archean at the northern fringe of the settlements has been cut, but the lumberman is still advancing northwards and approaching the northern limit of the famous Canadian white pine forests, beyond which spruces, tamarack (larch) and poplar are the prevalent trees. As one advances northward the timber grows smaller and includes fewer species of trees, and finally the timber line is reached, near Churchill on the west coast of Hudson Bay and somewhat farther south on the Labrador side. Beyond this to the north are the “barren grounds” on which herds of caribou (reindeer) and musk ox pasture, migrating from north to south according to the season. There are no permanent ice sheets known on the mainland of north-eastern Canada, but some of the larger islands to the north of Hudson Bay and Straits are partially covered with glaciers on their higher points. Unless by its mineral resources, of which scarcely anything is known, the barren grounds can never support a white population and have little to tempt even the Indian or Eskimo, who visit it occasionally in summer to hunt the deer in their migrations.

The Acadian Region.—The “maritime provinces” of eastern Canada, including Nova Scotia, New Brunswick and Prince Edward Island, may be considered together; and to these provinces as politically bounded may be added, from a physical point of view, the analogous south-eastern part of Quebec—the entire area being designated the Acadian region. Taken as a whole, this eastern part of Canada, with a very irregular and extended coast-line on the Gulf of St Lawrence and the Atlantic, may be regarded as a northern continuation of the Appalachian mountain system that runs parallel to the Atlantic coast of the United States. The rocks underlying it have been subjected to successive foldings and crumplings by forces acting chiefly from the direction of the Atlantic Ocean, with alternating prolonged periods of waste and denudation. The main axis of disturbance and the highest remaining land runs through the south-eastern part of Quebec, forming the Notre Dame Mountains, and terminates in the Gaspé peninsula as the Shickshock Mountains. The first-named seldom exceed 1500 ft. in height, but the Shickshocks rise above 3000 ft. The province of New Brunswick exhibits approximately parallel but subordinate ridges, with wide intervening areas of nearly flat Silurian and Carboniferous rocks. The peninsula of Nova Scotia, connected by a narrow neck with New Brunswick, is formed by still another and more definite system of parallel ridges, deeply fretted on all sides by bays and harbours. A series of quartzites and slates referred to the Cambrian, and holding numerous and important veins of auriferous quartz, characterize its Atlantic or south-eastern side, while valuable coal-fields occur in Cape Breton and on parts of its shores on the Gulf of St Lawrence. In New Brunswick the Carboniferous rocks occupy a large area, but the coal seams so far developed are thin and unimportant. Metalliferous ores of various kinds occur both in Nova Scotia and in this province, but with the exception of the gold already mentioned, have not yet become the objects of important industries. Copper and asbestos are the principal mineral products of that part of Quebec included in the region now under