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VIII. Note on an inequality in the Height of the Barometer, of which the Argument is 
the Declination of the Moon. By Sir J. W. Lubbock, Bart., Treas. and H.P.R.S. 
Received March 16, — Read March 18, 1841. 
In the Companion to the British Almanac for 1839, I inserted some results which 
were obtained with a view of ascertaining the influence of the moon on the barometer 
and on the dew-point. Mr. Luke Howard’s researches on this subject having re- 
called my attention to that paper, I find some results which I then gave seem to 
indicate that the moon’s position in declination influences the barometer. In order 
to render this more manifest, I shall now combine all the observations given in p. 3*, 
(and here recapitulated) in three categories. These observations correspond in part 
to different angular distances of the moon from the sun (or times of transit) ; but as 
the inequality of the Ocean, of which the argument is the moon’s declination, is 
independent (or very nearly so) of the time of the moon’s transit, it is probable that 
so also is that in the height of the barometer. In this case we may with propriety 
combine in the same category observations which correspond to similar declinations, 
although to different times of transit. 
The following are the results : 
No. of 
Observations. 
Moon’s 
Declination. 
Moon’s 
Parallax. 
Height of 
Barometer. 
Thermometer 
Attached. 
•78 
21*1 
57-4 
inch. 
30-063 
69-0 
167 
15-1 
56*9 
30-000 
67-7 
93 
4-4 
56*5 
29-1)60 
67-7 
This seems to indicate an elevation of nearly one-tenth of an inch for seventeen 
degrees of declination. The inequality has a contrary sign to the inequality of the 
same argument in the Tides of the Ocean. 
First Category. 
No. of 
Observations. 
Moon’s 
Declination. 
Moon’s 
Parallax. 
Height of 
Barometer. 
Thermometer 
Attached. 
12 
21-7 
58-3 
inch. 
30-022 
69-7 
13 
21-6 
58-5 
30-091 
69-9 
13 
20-2 
56-8 
30-057 
67-2 
16 
21-8 
56-4 
30-106 
67-6 
12 
21-2 
56-7 
30-037 
69-4 
12 
20-3 
58-0 
30-068 
70-5 
78 
126-8 
344-7 
180-381 
414-3 
Average. . 
21-1 
57-4 
30-063 
69-0 
* Companion to the British Almanac, 1839. 
L 
MDCCCXLI. 
