OBSERVATIONS TAKEN IN INDIA. 
307 
as usual fell gradually to 29‘373 at 3^ 41™ a.m. Although therefore the general pres- 
sure of the atmosphere had been lowered three or four-tenths of an inch from the 
20 th and 21 st of May, the daily tides had not been interrupted, the maxima and 
minima occurring at their usual hours. In a storm at Madras on the 24th of October 
1842, the p.M. tide reached its maximum at 10^ 41™p.m., but the ebb stopped at 
1*' 41™a.m. instead of 3^^ 41“ a.m., and then rose until 9'^ 41“a.m., the duration of the 
ebb being three hours only, and the flow from 1*’ 41“ a.m. to 9'' 41“ a.m., no less than 
eight hours ; the next ebb six hours, and the subsequent flow seven hours. One 
other illustration will show how little the pressure of the atmosphere is affected at a 
great height by a proximate storm. On the 17 th and 18th of April 1847 a great 
storm occurred on the Malabar coast. The following is the record of the barometer 
on the 17 th, at different distances from the centre of the storm, as recorded by 
Colonel Reid ; the Dodabetta observations being interpolated by myself. 
in. 
Madras, 300 miles distant from centre, barometer . . . 29’97 
Dodabetta, 166 miles distant from centre, barometer . . 2T917 
Cannanore, 100 miles distant from centre, barometer . . 29’64 
Ship Mermaid, 60 miles distant from centre, barometer . 29*35 
On the 18th of April. 
Madras, 400 miles distant from centre of storm, barometer 
Bombay, 240 miles distant from centre of storm, barometer 
Dodabetta, 196 miles distant from centre of storm, barometer .... 
Cannanore, 130 miles distant from centre of storm, barometer .... 
Ship Buckinghamshire, 20 miles distant from centre of storm, barometer 
Ship in centre of the storm, barom.eter 
29*94 
29*70 
21*984 
29*78 
28*35 
28*00 
At the centre of the storm, distant from Cannanore 130 miles, the difference of pres- 
sure therefore was 1*78 ; at Dodabetta, at 8642 feet above the sea, and 196 miles 
from the Buckinghamshire, the greatest difference on the 17 th, 18th, or 19th of April 
from the mean pressure of the month, was less than two-tenths of an inch, as the fol- 
lowing records at Dodabetta show : — 
1847. April 17 . 
April 18. 
April 19 . 
Mean pressure of 
month of April. 
Barometer. 
Oscillation. 
Barometer. 
Oscillation. 
Barometer. 
Oscillation. 
Barometer. 
Oscillation. 
2P917 
•058 
21-984 
•064 
22034 
•044 
22097 
•062 
And although the wind at Dodabetta on the \’]th and \^th blew from the east round 
to the west with a maximum jiressure of 35 and 22 lbs., and with a mean pressure for 
the two days of 2\ and 14 lbs. ; and though ten inches of rain fell on the \ Sth, the daily 
atmospheric tides ivere neither suppressed, inverted, nor interrupted, and scarcely differed 
from the daily mean oscillation of the month. Sufficient instances have thus been 
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