340 
IJEUT.-COLONEL SYKES’S DISCUSSION OF METEOROLOGICAL 
meteoiologist, to enable him to determine the normal or abnormal atmospheric phe- 
nomena of the locality in which the observations are taken ; and he will distrust the 
applicability of these local determinations to any other places situated beyond a cer- 
tain circumscribed area. 
With these remarks I proceed to consider the hygrometric features of certain widely 
separated stations in India, both at the sea-level and elevated at 1800 and 4500 and 
8640 feet above the sea. The most marked feature is the singularly small monthly 
mean depression of the wet bulb, the high figures of the elastic force of vapour, and 
the great per-centage of moisture in the atmosphere ; not only at the sea-levels of 
Madras, Bombay, Aden and Calcutta, but at Dodabetta, at 8640 feet above the sea, 
whether during the monsoons or during the cold and hot months, which are generally 
supposed to be the dry portion of the year, and the annexed Table exhibits the 
results. 
At neither of the Presidencies is there a mean monthly per-centage of vapour at 
Madras below 67, at Bombay below 66, at Calcutta below 63, and at Dodabetta 
below 51, while the maximum at Dodabetta goes up to 98, and at Calcutta to 94 ; at 
Bombay it did not exceed 88, and at Madras, in two years, it only twice attained a 
mean maximum of 83 per cent, of moisture in the atmosphere. The mean annual 
per-centage of moisture in the air, it will be seen for the years 1843 and 1844, was at 
Madras respectively 75 and 74^, at Bombay 76 and 76, at Calcutta 80 and 84, at 
Aden 71 , at Mahabuleshwur 67°'9, and at Dodabetta, for 1847-48, it was 90°. In the 
Deccan, in 1827, only 55°, as determined by Daniell’s hygrometer. The difference 
between the annual mean temperature of the air and the annual mean temperature of 
the dew-point, was — 
Madras. 
Bombay. 
Calcutta. 
Dodabetta. 
Deccan. 
Aden. 
Mahabuleshwur. 
1843. 
1844. 
1843. 
1844. 
1843. 
1844. 
1847-48. 
1827. 
1848. 
Means of 9 years. 
O 
O . 
0 _ 
O 
O 
O 
O 
O 
9 
9-24 
8-65 
8-65 
^•95 
5-3 
3-1 
17-9 
7-5 
12-2 
The air at Madras, Bombay and Calcutta, is unquestionably more moist than that 
of the interior ; but the feeling and experience so little lead one to expect the high 
dew-points indicated, particularly in the cold and hot months, that some inaccuracy 
of observation or fallacy in deduction might be feared, were not the ability and zeal 
of the observers at Madras and Bombay, combined with the observations being hourly 
a sufficient guarantee against error. At Calcutta, however, situated sixty miles from 
the sea, the hygrometric observations make the air much more moist even than at 
Madras and Bombay. This is contrary to probability, and may be owing to the means 
of the observations, made only twice a day, not giving the real mean of the twenty-four 
hours. At the peak or ridges of Dodabetta the air would appear to be nearly in a 
constant state of saturation ; and there is a possibility in the circumstance, consider- 
ing that it is the highest eminence in the peninsula of India and might be expected 
