31G 
LIEUT.-COLONEL SYKES’S DISCUSSION OF METEOROLOGICAL 
2Qth, 2\st^ 22nd or 23rd of May. The last irregularity to be notieed at Bombay, 
within the limit hours, was on the 2 1st of October. At midnight the barometer stood 
at 29 803 ; at 1 a.m. it had risen in the usual course to 29’887, but at 2 o’clock it had 
fallen to 29'881, and only resumed its ordinary rise at 3 a.m. ; as far as the record goes, 
there does not appear to have been any irregularity at Madras*. Similar instances 
occur within the limit hours in 1844, — on 21st of January at 3 a.m., 21st of May at 
1 A.M., when the tide remained stationary at 3*' 41“*, and 5 a.m., and at 1 a.m. on the 
22nd of December. In September the maximum horary pressure occurred at 
1 T* 30*** A.M., and in other months several times at 1 1 a.m. 
If we extend our comparisons to Aden, on the coast of Arabia, nearly in the lati- 
tude of Madras, but 35° 6' of longitude to the west of Madras, we find the very same 
exceptions to normal conditions. Dr. BuisThas been kind enough to transmit to me 
proof sheets, now going through the press, of part of a meteorological journal kept 
at Aden for 1847 and 1848. Hourly observations were taken on certain term-days 
monthly ; instead of taking up the whole of these term-days, it will suffice to select 
those of January and June of each year, these being months in which the maximum 
and minimum pressure of the atmosphere usually occur in India. Barometer 1*^7 feet 
above the sea at Aden. All corrections made. 
January, 
1847. 
Hours. 
Means. 
P.M. 
A..M 
Noon. 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
15 
29-760 
-743 
•821 
•778 
•780 
•770 
•853 
29-790 
25 
29 684 
-661 
• •• 
•717 
•646 
• •• 
•743 
29-691 
30 
29-763 
•716 
... 
... 
•786 
•722 
•808 
• •• 
29-760 
June, 
1847. 
8 
29-648 
•557 
... 
•637 
•583 
•698 
29-614 
16 
29-582 
•488 
•488 
•542 
•507 
. • 
•613 
29-533 
20 
29'631 
•502 
•574 
•506 
•620 
29-552 
29 
29 490 
•385 
• •• 
... 
•484 
•431 
•548 
29-468 
January, 
1848. 
7 
29-856 
•810 
•921 
•858 
•864 
•844 
•914 
29-876 
14 
29-868 
•835 
•902 
... 
... 
•860 
•915 
... 
29-874 
24 
29-791 
•732 
• •• 
•807 
•733 
... 
•853 
29-781 
28 
29-774 
•7'20 
•720 
•814 
•761 
•853 
29-781 
1 June, 
1848. 
8 
29-497 
-416 
•507 
•395 
•532 
29-460 
15 
29-546 
•481 
•549 
•479 
•572 
•563 
•609 
29-533 
21 
29-522 
•382 
•382 
•469 
•446 
•466 
•462 
•377 
•567 
29-456 
29 
29 651 
•542 
•599 
•544 
•673 
29-589 
A glance of the eye over the above Table shows the turning-points of the several 
tides and their irregularities. The first marked feature is the almost constant turn- 
ing of the descending p.m. tide and ascending a.m. tide at 3 p.m. and 3 a.m., instead 
of at 4 or 5 p.m. and a.m., as on the continent of India; to this there are only five 
* In a diagram of the comparative readings of seven barometers at Bombay, between the 20th and 21st of 
June 1843, these anomalies api)ear to have occurred between 2 and 3 p.m., 7 and 8 p.m., 10 and 11 p.m. and 
1 to 4 A.M., but the barometers did not exactly harmonize in their movements. 
