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 with the north-east trade-wind, and would accordingly blow without interruption throughout the year, were it not brought under the influence of a great counteracting cause. This is found on the central plains of Asia, which, becoming immoderately heated while the sun is north of the equator, rarify the surounding air, and thereby disturb the atmospherical equilibrium. To restore it, a current of colder air begins to rush in from the Indian Ocean. A kind of struggle takes place—the north-east monsoon endeavouring to maintain its direction, while the new current endeavours to establish its ascendency. In the struggle, the north-east monsoon is placed at great disadvantage, for at the very time when it is engaged with its opponent, part of its own forces are diverted,

and drawn off to the regions where the equilibrium has been disturbed. After a month of warfare, in which all the elements seem to mingle, and thunderstorms and hurricanes rage with the greatest fury, the new current prevails, and becomes established as the south-west monsoon. After blowing for nearly half a year, a new state of the atmosphere is superinduced. The overheated Asiatic plains are cooled down by the sun's departure for the south, the aerial struggle, with its accompanying thunder and hurricanes, is renewed, and in about a month the north-east monsoon, recovering its superiority, begins again to blow.

The effects of the monsoons in determining the climate of India are very remarkable. The south-west monsoon, in blowing over the Indian Ocean, becomes surcharged with vapour, which, being suddenly condensed on the heights of the Western Ghauts, is discharged in torrents. Thus deprived of its contents as fast as it anives on the Malabar coast, it blows across the country, and arrives at the Coromandel coast cis a dry wind. This cotist, accordingly, and the eastern part of the Deccan, generally at this time receive no direct supplies of rain, and become in consequence so parched, that the culture of the ground would become impossible, were it not that most of the rivers, having their sources in the Western Ghauts, become filled to overflowing, and thus furnish the means of carrying on an extensive system of irrigation. Beyond the limits of the Western Ghauts, the low plains near the mouths of the Indus, and the sandy desert to the east and north, are unable to attract any moisture from the monsoon, which now arrives well charged with water on the heights of the Himalaya. Being here deflected, it descends into the basin of the Ganges, and floods the lower plains of Bengal. The south-west monsoon having nm its course, the north-east monsoon repeats the process, though on a somewhat minor scale, because the Bay of Bengal, from which the moisture is derived, is of less extent, and therefore unable to supply it so copiously.

The course of the seasons in India will now be easily understood. In the seasons. British Islands, and in the temperate zone generally, winter, spring, summer, and autumn succeed each other, and the year performs its round of grateful vicissitudes. In India an entirely different arrangement takes place; and the Vol. I.