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CANADA . The Dominion of Canada comprises the See also:northern See also:half of the See also:continent of See also:North See also:America and its adjacent islands, excepting See also:Alaska, which belongs to the See also:United States, and See also:Newfoundland, still a See also:separate See also:colony of the See also:British See also:empire. Its boundary on the See also:south is the parallel of See also:latitude 490, between the Pacific Ocean and See also:Lake-of-the-See also:Woods, then a See also:chain of small lakes and See also:rivers eastward to the mouth of See also:Pigeon See also:river on the north-See also:west See also:side of Lake See also:Superior, and the See also:Great Lakes with their connecting rivers to See also:Cornwall, on the St See also:Lawrence. From this eastward to the See also:state of See also:Maine the boundary is an artificial See also:line nearly corresponding to See also:lat. 450; then an irregular line partly determined by watersheds and rivers divides Canada from Maine, coming out on the See also:Bay of See also:Fundy. The western boundary is the Pacific on the south, an irregular line a few See also:miles inland from the See also:coast along the " See also:pan handle " of Alaska to See also:Mount St See also:Elias, and the See also:meridian of 1410 to the See also:Arctic Ocean. A somewhat similar relationship cuts off Canada from the See also:Atlantic on the See also:east, the north-eastern coast of Labrador belonging to Newfoundland. See also:Physical See also:Geography.—In spite of these restrictions of its natural coast line on both the Atlantic and the .Pacific, Canadais admirably provided with harbours on both oceans. The Gulf of St Lawrence with its much indented shores and the coast of Nova See also:Scotia and New See also:Brunswick See also:supply endless harbours, the northern ones closed by See also:ice in the See also:winter, but the See also:southern ones open all the See also:year See also:round; and on the Pacific British See also:Columbia is deeply fringed with islands and fjords with well-sheltered harbours everywhere, in strong contrast with the unbroken See also:shore of the United States to the south. The See also:long stretches of sheltered See also:navigation from the Straits of Belle Isle north of Newfoundland to See also:Quebec, and for 600 m. on the British Columbian coast, are of great See also:advantage for the See also:coasting See also:trade. The greatly varied Arctic coast line of Canada with its large islands, inlets and channels is too much clogged with ice to be of much See also:practical use, but See also:Hudson Bay, a mediterranean See also:sea 85o m. long from north to south and 600 m. wide, with its outlet Hudson Strait, has long been navigated by trading See also:ships and whalers, and may become a great outlet for the See also:wheat of western Canada, though closed by ice except for four months in the summer. Of the nine provinces of Canada only three have no coast line on See also:salt See also:water, See also:Manitoba, See also:Alberta and See also:Saskatchewan, and the first may soon be extended to Hudson Bay. See also:Ontario has a seaboard only on Hudson Bay's southern See also:extension, See also: Owing to this unsymmetric development of North America the main structural See also:watershed is towards its western side, on the south coinciding with the Rocky Mountains proper, but to the northward falling back to ranges situated further west in the same mountain region. The great central See also:area of Canada is drained towards Hudson Bay, but its two largest rivers have separate watersheds, the See also:Mackenzie flowing north-west to the Arctic Ocean and the St Lawrence north-east towards the Atlantic, the one to the south-west and the other to the south-east of the Archean protaxis. While
these ancient events shaped the See also:topography in a broad way, its final development was comparatively See also:recent, during the glacial See also:period, when the loose materials were scoured from some regions and spread out as See also:boulder See also:clay, or piled up as moraines in others; and the See also:original water-ways were blocked in many places. The See also:retreat of the ice See also:left Canada much in its present See also:condition except for certain See also:post-glacial changes of level which seem to be still in progress. For this See also:reason the region has a very youthful topography with innumerable lakes and waterfalls as See also:evidence that the rivers have not long been at See also:work. The uneven See also:carving down of the older mountain systems, especially that of the Archean protaxis, and the disorderly scattering of glacial material provide most of the lake basins so characteristic of Canada.
Lakes and Rivers. As a result of the geological causes just mentioned many parts of Canada are lavishly strewn with lakes of all sizes and shapes, from bodies of water hundreds of miles long and a thousand feet deep to ponds lost to sight in the See also:forest. Thousands of these lakes have been mapped more or less carefully, and every new survey brings to See also:light small lakes hitherto unknown to the See also: There are nine others which have a length of more than See also:ioo m., and See also:thirty-five which are more than 50 M. long. Within the Archean protaxis they are of the most varied shapes, since they represent merely portions of the irregular surface inundated by some morainic See also:dam at the lowest point. Comparatively few have simple outlines and an unbroken surface of water, the great See also:majority See also:running into long irregular bays and containing many islands, sometimes even thousands in number, as in Georgian Bay and Lake-of-the-Woods. In the Cordilleran region on the other See also:hand the lakes are long, narrow and deep, in reality sections of mountain valleys occupied by fresh water, just as the fjords of the adjoining coast are valleys occupied by the sea. The lakes of the different regions present the same features as the nearest sea coasts but on a smaller scale. The majority of the lakes have rocky shores and islands and great variety of See also:depth, many of the smaller ones, however, are rimmed with marshes and are slowly filling up with See also:vegetable See also:matter, ultimately becoming See also:peat bogs, the muskegs of the See also:Indian. Most of Canada is so well watered that the lakes have outlets and are kept fresh, but there are a few small lakes in southern Saskatchewan, e.g. the See also:Quill and Old Wives lakes, in regions arid enough to require no outlets. In such cases the See also:waters are alkaline, and contain various salts in See also:solution which are deposited as a white rim round the basin towards the end of the summer when the amount of water has been greatly reduced by evaporation. It is interesting to find maritime See also:plants, such as the samphire, growing on their shores a thousand miles from the sea and more than a thousand feet above it. In many cases the lakes of Canada simply spill over at the lowest point from one basin into the next below, making chains of lakes with no long or well-defined channels between, since in so See also:young a country there has not yet been See also:time for the rivers to have carved wide valleys. Thus See also:canoe navigation may be carried on for hundreds of miles, with here and there a water-fall or a rapid requiring a See also:portage of a few hundred yards or at most a mile or two. The river systems are therefore in many cases complex and tortuous, and very often the successive connecting links between the lakes receive different names. The best example of this is the See also:familiar one of the St Lawrence, which may be said to begin as See also:Nipigon river and to take the names St See also:Mary's, St Clair, See also:Detroit and See also:Niagara, before finally flowing from Lake Ontario to the sea under its proper name. As theselakes are great reservoirs and settling basins, the rivers which empty them are unusually steady in level and contain beautifully clear water. The St Lawrence varies only a few feet in the year and always has pellucid bluish-See also:green water, while the See also:Mississippi, whose tributaries begin only a short distance south of the Great Lakes, varies 40 ft. or more between high- and See also:low-water and is loaded with mud. The St Lawrence is far the most important Canadian river from the historic and economic points of view, since it provided the main artery of exploration in early days, and with its canals past rapids and between lakes still serves as a great See also:highway of trade between the interior of the continent and the seaports of See also:Montreal and Quebec. It is probable that politically Canada would have followed the course of the States to the south but for the planting of a See also:French colony with widely extended trading posts along the easily ascended channel of the St Lawrence and the Great Lakes, so that this river was the ultimate See also:bond of See also:union between Canada and the empire. North of the See also:divide between the St Lawrence system and Hudson Bay there are many large rivers converging on that inland sea, such as See also:Whale river, Big river, East Main, See also:Rupert and Nottaway rivers coming in from See also:Ungava and northern Quebec; See also:Moose and See also:Albany rivers with important tributaries from northern Ontario; and See also:Severn, See also:Nelson and Churchill rivers from the south-west. All of these are rapid and shallow, affording navigation only for-canoes; but the largest of them, Nelson river, drains the great Manitoban lakes, See also:Winnipeg, See also:Winnipegosis and Manitoba, which are frequented by steamers, and receive the waters of Lake-of-the-Woods, Lake Seul and many others emptying into Winnipeg river from Ontario; of Red river coming in from the United States to the south; and of the southern parts of the Rocky Mountains and the western prairie provinces drained by the great Saskatchewan river. The parallel of 490 approximately separates the Saskatchewan waters from the streams going south to the See also:Missouri, though a few small tributaries of the latter river begin on Canadian territory. The northern part of Alberta and Saskatchewan and much of northern British Columbia are drained through the See also:Athabasca and See also:Peace rivers, first north-eastwards towards Athabasca Lake, then north through Slave river to Great Slave Lake, and finally north-west through Mackenzie river to the Arctic Ocean. If measured to the See also:head of Peace river the Mackenzie has a length of more than 2000 m., and it provides more than See also:i000 m. of navigation for stern-See also:wheel steamers. Unfortunately, like other northward-flowing rivers, it does not See also:lead down to a frequented sea, and so bears little traffic except for the northern See also:fur-trading posts. The Mackenzie forms a large but little-known See also:delta in lat. 69°, and in its See also:flood See also:season the head-waters pour down their torrents before the thick ice of the See also:lower part with its severer See also:climate has yet given way, piling up the ice in great barriers and giving rise to widespread floods along the lower reaches. Similar flooding takes See also:place in several other important northward-flowing rivers in Canada, the St Lawrence at Montreal affording the best-known instance. Second among the great north-western rivers is the See also:Yukon, which begins its course about i8 m. from See also:tide-water on an See also:arm of the Pacific, 2800 ft. above the sea and just within the Canadian border. It flows first to the north, then to the north-west, passing out of the Yukon territory into Alaska, and then south-west, ending in See also:Bering Sea, the northward See also:projection of the Pacific, 2000 M. from its head-waters. Of its course 1800 m. are continuously navigable for suitable steamers, so that most of the traffic connected with the See also:rich See also:Klondike See also:gold-See also:fields passes over its waters. The See also:rest of the rivers flowing into the Pacific pass through British Columbia and are much shorter, though the two southern ones carry a great See also:volume of water owing to the heavy precipitation of See also:snow and See also:rain in the Cordilleran region. The Columbia is the largest, but after flowing north-west and then south for about 400 m., it passes into the United States. With its expansions, the narrow and deep Arrow lakes, it is an important waterway in the Kootenay region. The See also:Fraser, next in size but farther north, follows a similar course, entering the sea at See also:Vancouver; while the Skeena and Stikine in northern British Columbia are much 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 See also:mining camps of the interior with their requirements. In most cases they reach the coast through deep valleys or profound canyons, and the transcontinental See also:railways find their way beside them, the Canadian Pacific following at first tributaries of the Columbia near its great See also:bend, and after-wards See also:Thompson river and the Fraser; while the See also:Grand See also: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 See also:sharp in the southern Rocky Mountains, but there are two lakes, the See also:Committee's See also: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 See also: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 See also:sources of See also:power. The St Lawrence system, for instance, generates many thousand See also:horse-power at Sault Ste See also:Marie, Niagara and the See also:Lachine rapids. All the larger cities of Canada make use of water power in this way, and many new enterprises of the See also: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 See also:day find use in manufactures like those of See also:Switzerland. The Archean Protaxis.—The broad geological and See also: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 See also:gneiss and See also:granite; but scattered through it are important stretches of See also: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, See also:schists and more or less metamorphosed sedimentary rocks, are of See also:special See also:interest for their ore deposits, which include most of the important metals, particularly See also:iron, See also:nickel, See also:copper and See also: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 Iofty 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 See also:case of schists forming narrow ridges, while the softer parts form valleys generally floored with lakes. From the See also:summit of any of the higher hills one See also:sees that the region is really a somewhat dissected plain, for all the hills rise to about the same level with a See also:uniform skyline at the See also:horizon. The Archean protaxis is sometimes spoken of as a See also:plateau, but probably half of it falls below r000 ft. The See also:lowland part includes from roo to Soo 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 See also: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 See also:bare roches moutonnees scoured by the glaciers of the Ice See also:Age, but a broad See also:band of clay See also:land extends across northern Quebec and Ontario just north of the divide. The edges of the protaxis are in See also: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 See also:gorges or canyons into the tableland. The waterfalls are utilized at a few points to work up into See also:wood pulp the forests of spruce which See also:cover much of Labrador, Quebec and Ontario. Most of the See also:pine that formerly See also: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 (See also:larch) and See also:poplar are the prevalent trees. As one advances northward the See also:timber grows smaller and includes fewer See also: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 (See also:reindeer) and See also: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 See also:mineral resources, of which scarcely anything is known, the barren grounds can never support a white See also:population and have little to tempt even the Indian or See also:Eskimo, who visit it occasionally in summer to See also:hunt the See also:deer in their migrations. The See also:Acadian Region.—The "maritime provinces" of eastern Canada, including Nova Scotia, New Brunswick and See also:Prince See also:Edward See also: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, maybe 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 See also:pro-longed periods of waste and denudation. The main See also:axis of disturbance and the highest remaining land runs through the south-eastern part of Quebec,forming the Notre See also:Dame Mountains, and terminates in the Gaspe See also:peninsula as the Shickshock Mountains. The first-named seldom exceed 1500 ft. in height, but the Shickshocks rise above 3000 ft. The See also:province of New Brunswick exhibits approximately, parallel but subordinate ridges, with wide intervening areas of nearly flat See also:Silurian and Carboniferous rocks. The peninsula of Nova Scotia, connected by a narrow See also: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 See also:Cambrian, and holding numerous and important See also:veins of auriferous See also:quartz, characterize its Atlantic or south-eastern side, while valuable See also:coal-fields occur in Cape See also: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 See also: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 See also:objects of important See also:industries. Copper and , See also:asbestos are the See also:principal mineral products of that part of Quebec included in the region now under description, although many other minerals are known and already worked to some extent. Extensive tracts of See also:good arable land exist in many parts of the Acadian region. Its surface was originally almost entirely wooded, and the products of the forest continue to hold a prominent place. Prince Edward Island, the smallest province of*Canada, is low and undulating, based on Permo-Carboniferous and Triassic rocks affording a red and very fertile See also:soil, much of which is under cultivation. The St Lawrence Plain.—As the St Lawrence invited the earliest settlers to Canada and gave the easiest communication with the Old See also:World, it is not surprising to find the wealthiest and most populous part of the country on its shores and near the Great Lakes which it leads up to; and this early development was greatly helped by the flat and fertile plain which follows it inland for over 600 m. from the See also:city of Quebec to Lake See also:Huron. This affords the largest stretch of arable land in eastern Canada, including the southern parts of Ontario and Quebec with an area of some 38,000 sq. m. In Quebec the See also:chief portion is south of the St Lawrence on the low plain extending from Montreal to the mountains of the " Eastern Townships," while in Ontario it extends from the Archean on the ,north to the St Lawrence and Lakes Ontario, See also:Erie and Huron. The whole region is underlain by nearly horizontal and undisturbed rocks of the Palaeozoic from the Devonian downward. Superimposed on these rocks are See also:Pleistocene boulder clay, and clay and See also:sand deposited in post-glacial lakes or an extension of the Gulf of St Lawrence. Though See also:petroleum and salt occur in the south-west peninsula of Ontario, metalliferous deposits are wanting, and the real See also:wealth of this See also:district lies in its soil and climate, which permit the growth of all the products of temperate regions. Georgian Bay and the northern part of Lake Huron with the whole northern margin of Lake Superior bathe the foot of the Laurentian plateau, which rises directly from these lakes; so that the older fertile lands of the country with their numerous cities and largely-developed manufactures are cut off by an elevated, rocky and mostly forest-covered See also:tract of the Archean from the newer and far more extensive See also:farm lands of the west. For many years this southern projection of the northern See also:wilderness was spanned by only one railway, and offered a serious hindrance to the development of the regions beyond; but settlements are now spreading to the north and rapidly filling up the See also:gap between east and west. The Interior See also:Continental Plain.—Passing westward by See also:rail from the forest-covered Archcan with its rugged granite hills, the,flat prairie of Manitoba with its rich See also:grasses and multitude of See also:flowers comes as a very striking contrast, introducing the Interior Continental plain in its most typical development. This great plain runs north-westward between the border of the Archean protaxis and the line of the Rocky Mountains, including most of Manitoba, the southern part of Saskatchewan and most of Alberta. At the See also:international boundary in lat. 49° it is 800 m. wide, but in lat. 56° it has narrowed to 400 M. in width, and to the north of lat. 62° it is still narrower and somewhat interrupted, but preserves its main physical features to the Arctic Ocean about the mouth of the Mackenzie. This interior plain of the continent represents the area of the ancient sea by which it was occupied in Mesozoic times, with a more ancient margin towards the north-west against the Archean, where undisturbed See also:lime-stones and other rocks of the Silurian and Devonian rest upon the downward slope of the Laurentian Shield. Most of the plains are underlain by Cretaceous and early See also:Tertiary shales and sandstones lying nearly unaltered and undisturbed where they were deposited, although now raised far above sea-level, particularly along the border of the 'Rocky Mountains where they were thrust up into foot-hills when the range itself was raised. These strata have been subjected to great denudation, but owing to their comparatively soft See also:character this has been, in the main, nearly uniform, and has produced no very bold features of See also:relief, Coal and lignitic coal are the principal economic minerals met with in this central plain, though natural See also:gas occurs and is put to use near See also:Medicine See also:Hat, and " See also:tar sands " along the north-eastern edge of the Cretaceous indicate the presence of petroleum.
Its chief value lies in its vast tracts of fertile soil, now rapidly filling up with settlers from all parts of the world, and the grassy uplands in the foot-See also: More important than the hills are the narrow and often rather deep river valleys cut below the general level, exposing the soft rocks of the Cretaceous and in many places seams of See also:lignite. When not too deep the river channels may be traced from afar across the prairie by the winding band of trees growing beside the water. The treeless part of the plains, the prairie proper, has a triangular shape with an area twice as large as that of Great See also:Britain. North of the Saskatchewan river groves or " bluffs " of trees begin, and somewhat farther north the plains are generally wooded, because of the slightly more humid climate. It has been proved, however, that certain kinds of trees if protected will grow also on the prairie, as may be seen around many of the older farm-steads. In the central southern regions the climate is arid enough to permit of " alkaline " ponds and lakes, which may completely dry up in summer, and where a supply of drinking-water is often hard to obtain, though the land itself is fertile. The Cordilleran See also:Belt.—The Rocky Mountain region as a whole; best named the Cordillera or Cordilleran belt, includes several parallel ranges of mountains of different structures and ages, the eastern one constituting the Rocky Mountains proper. This band of mountains 400 M. wide covers towards the south almost all of British Columbia and a See also:strip of Alberta east of the watershed, and towards the north forms the whole of the Yukon . Territory. While it is throughout essentially a mountainous country, very complicated in its orographic features and inter-locking river systems, two principal mountain axes form its ruling features—the Rocky Mountains proper, above referred to, and the Coast Ranges. Between them are many other ranges shorter and less See also:regular in trend, such as the See also:Selkirk Mountains, the Gold Ranges and the Caribou Mountains. There is also in the southern inland region an interior plateau, once probably a peneplain, but now elevated and greatly dissected by river valleys, which extends north-westward for 500 M. with a width of about Too m. and affords the largest areas of arable and pasture land in British Columbia. Similar wide tracts of less broken country occur, after a mountainous interruption, in northern British Columbia and to some extent in the Yukon Territory, where wide valleys and rolling hills alternate with short mountain ranges of no great See also:altitude. The Pacific border of the coast range of British Columbia is ragged with fjords and channels, where large steamers may go 50 or Too M. inland between mountainous walls as on the coast of See also:Norway; and-there is also a bordering mountain system partly submerged forming Vancouver Island and the See also:Queen See also:Charlotte Islands. The highest mountains of the Cordillera in Canada are near the southern end of the boundary separating Alaska from the Yukon Territory, the meridian of 141°, and they include Mount See also:Logan (19,54o ft.) and Mount St Elias (i8,000 ft.), while the highest See also:peak in North America, Mount See also:McKinley (20,000 ft.), is. not far to the north-west in Alaska. This See also:knot of very lofty mountains, with Mount Fairweather and some others, all snowy and See also:glacier-clad for almost their whole height, are quite isolated from the highest points of the Rocky Mountains proper, which are loos) m. to the south-east. Near the. height of land between British Columbia and Alberta there are many peaks which rise from 10,000 to 12,000 ft. above sea-level, the highest which has been carefully measured being Mount See also:Robson (13,700 ft.). The next range to the east, the Selkirks, has several summits that reach ro,000 ft. or over, while the Coast Ranges scarcely go beyond 9000 ft. The snow line in the south is from 7500 to 9000 ft. above sea-level, being lower on the Pacific side where the heaviest snowfall comes in winter than on the drier north-eastern side. The snow line gradually sinks as one advances north-west, reaching only 2000 or 3000 ft. on the Alaskan coast. The Rockies and Selkirks support thousands of glaciers, mostly not very large, but having some 50 or See also:loo sq. m. of snowfield. All the glaciers are now in retreat, with old See also:tree-covered moraines, hundreds or thousands of feet lower down the valley. The timber line is at about 7500 ft. in southern British Columbia and 4000 ft. in the interior of the Yukon Territory. On the westward slopes, especially of the Selkirks and Coast Ranges, vegetation is almost tropical in its See also:density and luxuriance, the See also:giant See also:cedar and the See also:Douglas See also:fir sometimes having diameters of 10 ft. or more and rising to the height of 150 ft. On the eastern flanks of the ranges the forest is much thinner, and on the interior plateau and in many of the valleys largely gives way to open grass land. The several ranges of the Cordillera show very different types of structure and were formed at different ages, the Selkirks with their core of pre-Cambrian granite, gneiss and schists coming first, then the Coast Ranges, which seem to have been elevated in Cretaceous times, formetl mainly by a great upwelling of granite and See also:diorite as batholiths along the margin of the continent and sedimentary rocks lying as remnants on their flanks; and finally the Rocky Mountains in the See also:Laramie or early See also:Eocene, after the See also:close of the Cretaceous. This latest and also highest range was formed by tremendous thrusts from the Pacific side, crumpling and folding the ancient sedimentary rocks, which run from the Cambrian to the Cretaceous, and faulting them along overturned folds. The See also:outer ranges in Alberta have usually the form of tilted blocks with a steep cliff towards the north-east and a gentler slope, corresponding to the See also:dip of the beds, towards the south-west. Near the centre of the range there are broader foldings, carved into See also:castle and See also:cathedral shapes. The most easterly range has been shown to have been actually pushed . 7 M. out upon the prairies. In the Rocky Mountains proper no eruptive rocks have broken through, so that no ore deposits of importance are known from them, but in the Cretaceous synclines which they enclose valuable coal basins exist. Coal of a bituminous and also semi-See also:anthracite kind is produced, the best See also:mined on the Pacific slope of the continent, the coking coals of the See also:Fernie region supplying the See also:fuel of the great See also:metal mining districts of the Kootenays in British Columbia, and of See also:Montana and other states to the south. The Selkirks and Gold Ranges west of the Rockies, with their great areas of eruptive rocks, both ancient and See also:modern, include most of the important mines of gold, silver, copper and lead which give British Columbia its leadership among the Canadian provinces as a producer of metals. In early days the placer gold mines of the Columbia, Fraser and Caribou attracted miners from everywhere, but these have declined, and lode mines supply most of the gold as well as the other metals. The Coast Ranges and islands also include many mines, especially of copper, but up to the present of less value than those inland. Most of the mining development is in southern British Columbia, where a network of railways and waterways gives easy See also:access; but as means of communication improve to the north a similar development may be looked for there. The Atlin and White Horse regions in northern British Columbia and southern Yukon have attracted much See also:attention, and the Klondike placers still farther north have furnished many millions of dollars' See also:worth of gold. Summing up the economic features of the Cordilleran belt, it includes many of the best coal-mines and the most extensive deposits of gold, copper, lead and See also:zinc of the Dominion, while in silver, nickel and iron Ontario takes the lead. When its vast area stretching from the international boundary to beyond the Arctic circle is opened up, it may be expected to prove the counterpart of the great Wining region of the Cordillera in the United States to the south. Climate.—In a country like Canada ranging from lat. 420 to the Arctic regions and touching three oceans, there must be great See also:variations of climate. If placed upon Europe it would extend from See also:Rome to the North Cape, but latitude is of course only one of the factors influencing climate, the arrangement of the ocean currents and of the areas of high and low pressure making a very wide difference between the climates of the two sides of the Atlantic. In reality the Pacific coast of Canada, rather than the Atlantic coast, should be compared with western Europe, the south-west corner of British Columbia, in lat. 48° to 5o°, having a climate very similar to the southern coast of See also:England. In Canada the isotherms by no means follow See also:parallels of latitude, especially in summer when in the western half of the country they run nearly north-west and south-east; so that the average temperature of 550 is found about on the Arctic circle in the Mackenzie river valley, in lat. 500 near the Lake-of-the-Woods, in lat. 55° at the northern end of James Bay, and in lat. 490 on See also:Anticosti in the Gulf of St Lawrence. The proximity of the sea or of great lakes, the elevation and the direction of mountain chains, the usual path of storms and of prevalent winds, and the relative length of day and amount of See also:sunshine in summer and winter all have their effect on different parts of Canada. One cannot even describe the climate of a single province, like Ontario or British Columbia, as a unit, as it varies so greatly in different parts. Details should therefore be sought in articles on the separate provinces. In eastern Canada Ungava and Labrador are very chill and inhospitable, owing largely to the See also:iceberg-laden current sweeping down the coast from See also:Davis Strait, bringing fogs and long snowy winters and a temperature for the year much below the freezing-point. South of the Gulf of St Lawrence, however, the maritime provinces have much more genial temperatures, averaging 40° F. for the year and over 6o° for the summer months. The amount of rain is naturally high so near the sea, 40 to 56 in., but the snowfall is not usually excessive. In Quebec and northern Ontario the rainfall is diminished, ranging from 20 to 40 in., while the snows of winter are deep and generally cover the ground from the beginning of See also:December to the end of See also: There is a much lighter snowfall in winter than in northern Ontario and Quebec, with somewhat lower temperatures. The snow and the See also:frost in the ground are considered useful as furnishing moisture to start the wheat in See also:spring. The precipitation in southern Saskatchewan and Alberta is much more variable than farther east and north, so that in some seasons crops have been a failure through drought, but large areas are now being brought under See also:irrigation to avoid such losses. The prairie provinces have in most parts a distinctly continental climate with comparatively short, warm summers and long, cold winters, but with much sunshine in both seasons. In southern Alberta, however, the winter cold is often interrupted by chinooks, westerly winds which have lost their moisture by See also:crossing the mountains and become warmed by plunging down to the plains, where they See also:blow strongly, licking up the snow and raising the temperature, sometimes in a few See also:hours, from 20° to 40° F. In this region cattle and horses can generally winter on the grass of the ranges without being fed, though in hard seasons there may be heavy losses. Additional information and CommentsThere are no comments yet for this article.
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