308 
LIEUT.-COLONEL SYKES’S DISCUSSION OF METEOROLOGICAL 
adduced of the comparatively narrow area of very great barometrical depressions, 
and the annual ranges given in the preceding Table may for the present be considered 
normal conditions, at least at Madras. 
The following Table gives the monthly means of the diurnal oscillation of the baro- 
meter at Dodabetta, together with the monthly and annual range of the barometer, 
and the monthly fall of rain : — 
Barometer at Dodabetta, at 8640 feet above the level of the sea. 
Barometer. 
Monthly means. 
Diiference. 
Maximum. 
Minimum. 
Extreme 
monthly range. 
Rain. 
1847. 
February 
9*“ 40' A.M. 
in. 
22-129 
3'“ 40' p.M. 
in. 
22-068 
-061 
in. 
22-165 
in. 
22-014 
•151 
7-43 
March 
22-160 
22-105 
-055 
22-218 
22-064 
•154 
3-61 
April 
22-128 
22-066 
•062 
22-199 
21-888 
•311 
19*80 
May 
22-087 
22-024 
•063 
22-169 
21-930 
•239 
4-86 
June 
21-992 
21-940 
•052 
22-069 
21-800 
•269 
4-55 
July 
22-000 
21-949 
•051 
22-032 
21-889 
•143 
7-41 
August 
22-030 
21-976 
•054 
22-090 
21-898 
•198 
9*32 
September 
22-031 
21-977 
•054 
22-100 
21-876 
•224 
7-52 
October 
22-086 
22-014 
•072 
22-129 
21-958 
•171 
12-49 
November 
22-117 
22-038 
•079 
22-152 
21-966 
•186 
11-85 
December 
22-073 
22-013 
•060 
22-150 
21-921 
•229 
12-28 
1848. 
January 
22-113 
22-050 
•063 
22-163 
22-016 
•147 
0-12 
Year 
22-079 
22-019 
•060 
22-218 
21-800 
•418 
101-24 
Horary Oscillations. 
It is thus shown that the mean daily range for the year is 0’060, and in no month of 
the year did it exceed 0‘079 in. This is different from Mahabuleshwur, Poona, Madras 
and Bombay. At Mahabuleshwur, at 4500 feet, the mean diurnal oscillation for ten 
months, by simultaneous observations, was 0 0694, and in no month did the monthly 
mean exceed 0’0835. At Poona, at 1823 feet, for 1827, it was 0T009, for 1828 it was 
0*1075, and for 1829 it was 0*0991 ; but this last diminished oscillation is partly to 
be attributed to three months’ observations having been taken at an elevation of 4000 
feet above the sea; but in 1830 the barometers were stationed for the whole year at 
Poona, at 1823 feet, and the mean diurnal fall of the barometer from 9 — 10 a.m. to 
4 — 5 p.m. was 0*1166; the mean of the four years was 0*1060. The greatest mean 
diurnal range for any month in those four years was 0*1616 in the month of Decem- 
ber 1827. At Madras hourly observations were recorded from the years 1842 to 1845, 
both inclusive, and for ten months in 1841, of which I shall not take any account, as 
the year is incomplete. The mean monthly fall of the barometer from O'* 41“‘a.m. to 
3 b 4 jm p claily, was respectively 0*124, 0*120, 0*122 and 0*121, exhibiting a singular 
uniformity, the differences being only in the thousandths of an inch of pressure. This 
uniformity is equally marked in the successive months of the several years, and I have 
gone through the labour of working out the details to show it, the Madras printed 
observations being a record of facts only without deductions or comment. 
