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XVII. Observation of the Winter Solstice o/" 1812, with the Mural 

 Circle at Greenwich, By John Pond, JE^^. Astronomer Royal^ 

 F.R.S, 



Read February 25, 1813. 



1 H E weather this year at the period of the solstice was pecu- 

 liarly unfavourable for astronomical observation ; however, in 

 the course of the month, I obtained nine observations of the 

 sun ; one of these proved defective, the result of the other 

 eight, accompanies this communication. In my observation 

 of the summer solstice, it will be seen that I assumed the arc 

 ZP equal 38*31' 2i"i5; by subsequent observation I conceive 

 that I have somewhat improved this quantity, which I now 

 assume 38** 31' 21^,5, as resulting from 120 observations of 

 Polaris. 



The observation of the summer solstice thus corrected will 

 give the mean obliquity of the ecliptic for January 1, 1813, 

 ^3*" *7' 5i"j50j and the winter solstice 23" 27' 47",35. 



There can be no doubt but this small discordance might 

 easily be reconciled by a slight modification of Bradley's 

 refractions, and perhaps ultimately it may be necessary to 

 have recourse to this theory for its explanation ; but I am un- 

 willing to do this hastily, being now occupied in making an 

 extensive series of observations of circumpolar stars, with a 

 view of determining, if possible, whether Bradley's mean 

 refraction does, or does not, require alteration. — As I propose 

 making the discordance of the solstices the subject of a sepa- 



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