Such is the great constant wind, with its dependents. So long as the sun has warmed the earth, it has hurried on its course, subject to unceasing law, and destined to cease only when the heavens and the earth shall pass away, and chaos or annihilation shall end the things that be. A Wandering Jew of the atmosphere, it flies ever onward, bearing the merchant to his port, and the rain-cloud to the land; ever and anon desolating the isles with its bursts of fury; then resuming its restless course, like the remorseful Salathiel. CHAPTER III. PERIODIC WINDS. “Earth has each year her resurrection hours When the spring stirs within her, and the powers Of life revive; the sleeping zephyrs rouse, The blushing orchards clothe their naked boughs, The swallow skims above the lakelet’s verge. Swift summer speeds with fire in every vein, And autumn’s glories crimson hill and plain. Then warmth and life from Nature take their flight, And winter robes her in a shroud of white, While mournful Boreas chants her funeral dirge.” So the seasons tread their ceaseless round in the temperate zones, and to a certain degree in the colder regions of the earth. But when we examine the change of seasons in the tropical world, we find a state of things so different that we are at once led to inquire the reason: and it will be found primarily in certain periodical winds. When the sun is north of the equator: that is, while our northern summer is in progress, India enjoys a steady sea wind from the southwest, which brings a rainy season to the corresponding coasts of Hindostan and Farther India. When the sun returns to the south, the winds set in from the opposite direction, coming down across the great upland plateau of Central Asia, sometimes called, from its immense height and extent, the “Roof of the World.” These periodic winds are called monsoons: a corruption of the Arabic word _Moussin_, season. They are in reality a modification of the trade-winds. A glance at a map will show that the northern half of the great Indian Ocean is enclosed by land masses as no other large body of water is. Consequently, while in the southern section the southeast trade is present, the northeast trade of the northern part is so modified by the surrounding land areas as to almost entirely lose its distinctive character. Hence, most tropical regions have, properly speaking, but two seasons: the rainy, and the dry. As the clouds swept in meet with an intensely heated region, the trade never chills them sufficiently to produce snow, except in extremely elevated regions.