Page:Madras Journal of Literature and Science, series 1, volume 6 (1837).djvu/317

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1837.]
Meteorology of the Gomsoor Mountains.
295

IV.—Meteorological Experiments made on the Goomsoor Mountains.—By Lieut. John Campbell, Assistant Surveyor General.

These observations are, from the want of leisure and from the inconveniences of a moving camp, necessarily very imperfect, but, in the absence of better, they are offered to the public, for the purpose of shewing the approximate height of the hilly tract west of Goomsoor, and in the hopes they may be of some use in shewing the relation between the wet bulb thermometer and the dew point; but no inferences on this subject have been attempted, in consequence of my not having seen Professor Anjohn's formula for this purpose; and on this account some preparatory observations, made with the instrument at different places in the Northern Circars, have been added to the register.

The hilly ranges of Goomsoor form part of an elevated tract of mountainous country, which extends from Gundipoor and Battily on the Calingapatam river, on the south, up to the Mahanuddy on the north. Their average distance from the sea is about thirty or forty miles, and they extend inland in width about sixty miles, where they meet the plains of the Sompore, Potanalkaulahunchy, and Jeypore countries. The extreme elevation is 2,500 feet above the sea; the lowest 2,000 feet.

In the south they are inhabited by a race of men called Sowrahs; in the north by the Khonds: these races in manners and habits are much the same, and both are distinguished by a peculiar pectoral mode of enunciating, although the language of both is quite different. The average height of the hills above the diluvial soil which fills up the valleys between them is about 1,500 feet, they are composed of granitic, trap, and porphyritic rocks, and are generally but scantily covered with jungle.

During the time the observations were made the climate was in general pretty healthy, and although sometimes the dew point underwent great alterations, yet it was commonly pretty regular; although it was found that, before the dew in the morning had been dissipated by the sun's rays, the hygrometer commonly gave the dew point two or three degrees too low.

The thermometer used was a small one of a six inch scale by Dollond, which agreed pretty well with the thermometer in the stem of the hygrometer by Newman. The wet thermometer was a small one taken out of the ball of a Daniel's hygrometer by Jones, and the bulb