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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 V.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 : 



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. 



MDCCCXLI. 



* Companion to the British Almanac, 1839. 

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