BRITISH COLUMBIA.—This section of the Western Cordillera, although considered as one natural region, really consists of a large number of such regions, each of which conforms to one or other of a few distinct types. It extends from the Rocky Moun tains in the east to the coastal ranges on the west, and includes both ; in the south the intervening land is occupied by a grouping of several irregular ranges, and in the north between the 58th and 60th parallels there is a mountainous country which separates it from the Yukon Plateau lying beyond. To the west of the Rocky Mountains, in the south, and separated from them by the Upper Columbia and Kootenay rivers, is the Selkirk Range, which in turn is separated from the Gold Range by the southward flowing Col umbia. Beyond this lies what is known as the Interior Plateau, a mountainous region with an average height of about 3,500 feet, intersected by river valleys, which, in the case of the large ones, do not rise to an elevation of more than 1,000 feet above sea-level, while the intervening heights seldom exceed 5,000 feet. The west coast is much broken up by deep, fiord-like indentations, and is fringed by a long chain of islands, which are the continuation northwards of the Olympic mountains of Washington.
The geological formation of the region is extremely complicated. The Rocky Mountains and Vancouver Island consist chiefly of sedimentary measures of Palaeozoic age which contain infolded Mesozoic strata ; the coastal ranges are built up of granitic rocks; while the interior plateau contains large tracts of country covered by volcanic rocks of Tertiary times, and great areas of intrusive granitic rocks. Further north, wide stretches of Cretaceous rocks are found.
The climate of the whole of this region is very different from that of Eastern and Central Canada, and is determined mainly by the prevailing westerly winds which, blowing over the North Pacific, are relatively warm in winter and cool in summer. Thus the range between summer and winter temperatures is greatly reduced as the following figures show :— Mean temperature for Mean temperature for three coldest months. three warmest months.
Victoria .. .. F. F.
Kamloops.. In winter the isotherms run from north-west to south-east, while in summer they trend northwards, more or less parallel to the coast, before making their great bend to the south-east. The precipita
tion of the whole region varies greatly. Along the windward slopes of the coastal mountains it is very high, being frequently between 70 and 100 inches, and on some of the islands even the latter amount is exceeded. On the leeward slopes it decreases, and over a wide belt running north and south across the Interior Plateau it does not exceed 10 inches ; but on the west side of the Rocky Mountains it increases again to over 30, and in some places to over 40 inches per year.
The vegetation of the region varies with climate. The greater part, except in the north, is forested, but in the southern interior, where the rainfall is low, there are wide stretches of grassland. Among the more valuable trees are the Douglas fir, the red cedar, the yellow cedar, the maple, and the western oak. Next to mining, lumbering is the most important industry of British Columbia, and large quantities of valuable wood are exported. Within recent years, sawmills have been set up in the mountainous districts away from the coast for the supply of timber to the treeless plains further east. Preparations are also being made for the establishment of pulp factories.
Agricultural conditions differ considerably from those prevailing east of the Rocky Mountains. There is much fertile land, but it is scattered throughout the country, in the river valleys, along lake shores, on the deltas, and in other districts which have been cleared of timber. In the dry belt, where grassland occurs, irrigation is necessary to ensure good crops. Mixed farming is general in the southern part of the province. Cereals are grown in many places, but are chiefly used for feeding stock, ranching being an important industry. Further north, along the route of the Grand Trunk Pacific Railway, and in the Peace and Athabasca river districts, more attention is being paid to the cultivation of wheat, but the amount produced is still small. As much of the land is forested, and as cultivation is more difficult than in the east, it is probable that progress will be slow, and that it will not be until more intensive cultivation is necessary in the Winnipeg Basin that wheat-growing on a large scale will prove remunerative west of the Rocky Mountains.