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 Modifying Clauses.

Heat

these causes are so numerous, and operate so differently in different localities, that it may be truly .said to have not one, but many climates. Northwards a few degrees from the tropic, it has a region in which snow and ice are never wanting; westwards, it has a desert with the parched plain and scorching heats of the African Sahara; eastwards, it has a deep alluvial basin overcharged with moisture; and southwards, while the isothermal line, indicating the greatest quantity of mean annual heat on the surface of the globe, crosses it obliquely from the Coromandel to the Malabar coast, the Neilgherry Hills, situated nearly in the same latitude, enjoy the climate of the finest part of the temperate zone. Where so many anomalies exist, it would obviously be impossible to give an adequate description, without entering into numerous as complicated details; and therefore the utmost which can here be done is to point out a few features which, though much diversified by circumstances, may be considered characteristic of the climate of India.

The most prominent of these features are heat and humidity—heat produced chiefly by the direct action of the sun's rays, but intensified in many districts by alow level, a natm-ally arid soil, and sultry winds from other countries; and humidity, not derived, as in Europe, from moderate showers occurring more or less at all seasons, but the result of rains which occur regularly at stated periods, and are so copious and incessant as often to pour down more water in a month than falls in any part of England in a year. In London, the mean annual temperature is 49.35°; in Calcutta it is 79 37°; in Bombay, 8.19°; in Madras, 84.4° In order to perceive the full effect of these differences, it is necessary to attend to the annual range of temperature, or the number of degrees between the greatest mean heat and the greatest mean cold. In London, this range amounts to no less than 40.3° whereas in the above three cities it amounts respectively to no more than to 11.9°. 10°, and 72°. In other words, heat is far more equally diffused in India than in our own island ; and the complete cessation of vegetation which takes place in the latter during the rigour of winter, is totally unknown in the former. An equally striking contrast appears in the degrees of humidity. The average annual fall of rain in England is 32 inches. In Bombay, as large a quantity has been known to fall in twelve days, while the average of the year is about 85 inches. On the Malabar coast and many parts of the Western Ghauts, even this quantity is largely exceeded, and the average has been estimated at 136 inches. This, however, is only a local extreme. In Calcutta, the range of the fall is from 50 to 85 inches; and on the Coromandel coast, in the neighbourhood of Madras, the annual average of England is supposed not to be exceeded.

The great agents in reguating; the climate of India and fixing its character, are the periodical winds known by the name of monsoons. With the interval of about a month, they divide the year between them—the one blowing regularly from the north-east from October to March, and the other from the south-west from April to September. The north-east monsoon is, strictly speaking identical