Such are the plants which form the characteristic vegetable product of temperate regions. Wheat, which will not thrive in hot climates, flourishes all over the Temperate Zone, at various ranges of elevation. Maize spreads over an immense geographical area in North America, as well as in Southern Europe. Barley is cultivated in those parts of Europe and Asia where the soil and climate are not adapted for wheat; while oats and rye extend far into the bleak North, and disappear only when we reach those desolate Arctic regions where man cannot exist in his social capacity. By such striking adaptations of different varieties of grain to gradations of climate and varieties of soil, does Providence furnish the food indispensable for the sustenance of the human race.
Again: what are the trees that are most useful to man in a high state of civilization? Unquestionably those yieldingthe largest supply of common timber. Now the chief fancy- wood trees-those which form part of man"s luxuries-belong to the Tropics; but the pines and hard-wood trees-those which minister to man"s necessities-belong distinctively to the Temperate Zone. The inhabitant of that zone must send to Honduras for mahogany, to Brazil for rosewood, to make his finer furniture; but the pine, the ash, the oak, the elm, the beech-the timber used in building his houses and work- shops, the wood used in fashioning his tools and carts and carriages, and in making his most complicated machinery- these he finds abundantly in his own woods. They are reared in the same climate, they breathe the same air as himself.
What is true of the vegetable world above the soil, is true also of the mineral world beneath it. All the metals most useful to man, both for domestic and for industrial purposes- iron, tin, copper, lead-are found in abundance within the temperate regions. Coal, too, without which the ores could not be profitably smelted or supplied in sufficient quantities, and which is the main-spring of all manufacturing industry, is most plentiful in the Temperate Zone.
But very marked differences occur within the Temperate Zone itself-the result of differences of climate and configuration. Central Asia, for example-indeed, the whole of Asia north of the line of the Caucasus, the Himalaya, and④the Chinese Wall-consists of barren steppes, which now,
as much as six centuries ago, are the home of barbarism and rapine. And why is this? Because its inland deserts are far removed from the influences of the sea; because lofty mountains give most of its land a northern aspect; because its rivers flow either into salt lakes with no outlet, or into a frozen ocean which completely shuts out commerce.
Look at Europe on the other hand. It is of all the continents the one which is most thoroughly broken up by inroads of the sea. Asia is four and a half times as large as Europe insuperficial area; yet Europe has a coast-line five times as great as that of Asia. Excepting only the plains of Russia, no part of Europe is more than three hundred miles distant from the sea; while the number and the distribution of its navigable rivers bring the ocean within easy reach even of its remotest parts.
And what are the consequences of this? A glance at the map of Europe will tell us. It is evidently the continent most thickly covered with cities and towns; and with high-roads, canals, and railways, weaving the towns into a living and ever- busy net-work. There civilization has struck its roots deepest, and stretched its branches widest. There the arts and sciences have reached their highest development. There the great mechanical inventions which have knit the world into one vast inter-dependent society, have had their birth; and commerce, manufactures, and agriculture have been brought to the greatest perfection.