Climatically the American Mediterranean does for us what its namesake does for Europe. Without the Caribbean Sea and the Gulf of Mexico the central United States would be far drier than now. Louisiana would be as dry as New Mexico, and even in Iowa the aridity would do much harm to farming. As things are now, much of the rainfall of the Mississippi Valley, especially in summer, comes from the Gulf of Mexico.
The Continents: How Asia's Location Gives it Connections by Land.--Having considered the general relations of the continents, and the way in which they are united or divided, let us consider each continent separately, paying special attention to location, size, relief, shape, and relation to the sea. To begin with Asia, its location is noteworthy because the continent is very central so far as land com munication is concerned. Asia is the only continent that has a direct land connection with two other continents. Hence western Asia,. being closely connected with Europe and Africa, has had a great influence upon both, and thus largely determined the kind of civiliza tion which came to North America after the use of ships overcame the water barrier. How true this is we may judge from the fact that from Asia by way of Europe we have received our language, letters, and numerals. Our chief domestic animals, the horse, cow, sheep, pig, and hen are all of Asiatic origin. Wheat and barley, as well as rice and millet, were apparently brought to the other continents from Asia, so that all of our chief sources of food except corn and potatoes were derived from Asia. In later times Christianity, Judaism, and Mohammedanism all spread westward from this great continent not only into Africa but into Europe and thus into America.
How the Size of Asia is a Handicap.—In spite of the advantage of its position in the center of the lands Asia is seriously handicapped by its size. Because of the size vast tracts are so far from the ocean that they are deserts. The few inhabitants are very backward, not only because the dryness keeps them in hopeless poverty, but because their remoteness and the difficulties of travel keep them from coming in contact with other people whose ideas might spur them to new efforts. Many of the Khirghiz, for example, do not know the difference be tween Americans and Tibetans, and think a man is lying when he tells them how fast he can go on skates, which most of them have never heard of. Everywhere the size of Asia leads to great climatic ex tremes. Hence the disasters are on a scale unparalleled elsewhere.
When drought ruins the crops in India or when tremendous floods swamp the rice fields of China gaunt famine menaces tens of millions of people.
How the Relief of Asia Keeps Countries Apart.—The relief of Asia is as great a handicap as the size, for Asia possesses the world's highest mountains, greatest plateaus; and deepest depressions below sea level. The main feature of Asiatic relief is a vast band of moun tains and plateaus which extends from Asia Minor eastward through the Elburz Mountains across the whole of Persia and Afghanistan to a huge knot in the Pamirs northwest of India. Then the band broad ens fanwise; one side, the Tian Shan, Altai, and Yablonoi ranges, striking northeast toward Bering Strait; and the other, the Hima layas and Burmese Mountains, southeast to the Malay Peninsula. How great a barrier these mountains are may be judged from the fact that though China and India are close together, no railroad connects them, and far more caravans go from China to Siberia than from China to India.
How the Shape of Asia and its Relation to the Sea Depart from the Ideal.—The shape of Asia is no more favorable than its relief. The continent has many great peninsulas, but the sea rarely penetrates far inland. So bulky is Asia that the interior contains an area the size and shape of the United States with every part more than 1000 miles from the sea. On the north many harbors that might otherwise be used are blocked with floating ice, and only since the invention of ice breakers and of wireless telegraphy to warn of the presence of ice has it been possible for ships to reach the mouths of the great Siberian rivers without the greatest risk. On the southwest the uplifted shores of Arabia and Persia with their smooth, narrow coastal plains are devoid of good harbors. Almost the only native sailors are a few fishers for sponges and pearls chiefly in the Persian Gulf. The only good harbor from Suez to India is at Aden. India is more favored than the countries farther west, for Bombay and Calcutta are good ports, but between them the mainland has no really good harbor. From Singapore to Kamchatka, however, the many indenta tions show that the land has been submerged or " drowned," so that the water has entered the valleys and surrounded many of the out lying mountain ranges such as Japan and Formosa. So there the junks of the Japanese and Chinese dot the waters with their colored sails just as the boats of the Greeks abound off the coast of Asia Minor where similar conditions prevail.