1836.] Abstract of Meteorological Tables. 819 



inserted, under the Bancoora column, heading the index line 23.50, 

 to correspond with the average range of the barometer at Simla* 

 and have reprinted the plate. 



The first feature in the table that attracts attention is an almost per- 

 fect parallelism in the march of the barometer at Calcutta, Bancoora, 

 Mozafferpur, Cawnpore, Nipal and Simla — places situated many hun- 

 dred miles asunder from 22^° to 28° north latitude, and 80° to 88° east 

 longitude, with altogether differently prevailing winds and climates, 

 and opposite geographical features. The same parallelism continues, 

 even as far south as Madras, but the excursions are there much sub- 

 dued in every respect, and occasional deviations are observable, which 

 seldom or never occur in the three Gangetic lines, except from such a 

 local hurricane as that experienced in the immediate neighbourhood 

 of Calcutta on the 3rd August, 1834. Between Bombay and Calcutta, 

 little conformity of detail can be perceived, though the general direc- 

 tion is symmetrical. There is, however, considerable accordance 

 between Bombay and Madras, the former having from its higher 

 latitude a wider range of oscillation, both annual and intermediate. 



The direction of the wind (at least of the lower stratum) alone 

 seems quite insufficient to account for the barometrical variations, al- 

 though it is generally true that the mercury rises with the prevalence 

 of northerly, and falls with that of southerly winds, as might be expected 

 from the different specific gravity of a warmer or colder atmospheric 

 column. That the moon also has no regular influence appreciable on 

 the scale of my table, must be, I think, also granted ; for as many 

 instances occur of a falling as of a rising barometer at the changes of 

 lunar phases. The course of the thermometer, on the contrary, seems 

 to have a decided connection with that of the barometer. This is 

 exemplified in the comparative uniformity of the Madras line, and the 

 increased curvature at other places. For convenience of division I 

 assumed the tenth of an inch, as representing 10 Fahrenheit degrees of 

 temperature. Had I taken double that amount, the general thermome- 



* Having the former copy of the plate at hand, I have distributed it detached 

 along with the other, hoping it may attract notice and procure me a fuller 

 collection for some future year. 



I have been also favored with a daily barometrical series for 1836 at Bangalore, 

 by Dr. Mouat, but 1 have reason to think that the instrument used was sluggish 

 in its movements. I trust, however, for the ensuing year, the labours of this zeal- 

 ous observer will be made available by the possession of better instruments. I 

 have further many other broken series from Assam, Kyouk Phyoo, Candy, &c. 

 but they are generally wanting in the barometer. A short series was also kept 

 for me by Lieutenant Montrion, I. N. at the head of the bay in January and 

 February, 1833. 



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