248 PROCEEDINGS OF THE AMERICAN ACADEMY 



1755. — Bradley. I have used Peters's reduction of the A. R. of 

 Polaris. 



1785. — Maskelyne. The introduction of the known coefficient of 

 nutation into Lindenau's conditional equations for this observer, as 

 well as of L.'s own aberration and parallax, which are very accurate, 

 enabled me to determine the A. R. from 1785, given in the Table with 

 the proper motion -j- 0^065 for the same date ; whicl^ reduced to 

 1855, is equal to 0^082 ; a quantity sufficiently accurate to show that 

 the progress of wear in the Greenwich transit-instrument would not 

 affect our result seriously. 



A trifling change (of about 0^04) for the better in the representa- 

 tion of Bradley's observations would be made by omitting Maskelyne 

 altogether. 



1815, 1820. — Carlini. From the Effemeridi Astronomiche de Mi- 

 lano, 1821, p. 106 of the Appendix. 



1817. — Bessel. Observations with the Dollond Transit, 1814- 

 1819. Tabular Regiomontanas, p. xliii. 



1819. — Struve. Observationes Dorpatenses, III. liii. The latest 

 tables of Bessel referred to are in Volume IV. of the Konigsberg 

 Observations. I have added 0M9 to Struve's results, to refer them 

 to his own later determination of the fundamental stars. 



1824. — Bessel. Loco modo citato. Observations with the Reichen- 

 bach circle, 1820-28. 



1824, 1832. — Dorpat (Struve and Preuss). See Peters's Nume- 

 rus Constans Nutationis, p. 18. The quantity w was considered 

 as the correction of A. R. for 1824, according to Struve, and iv-\-w' 

 that for 1832, according to Preuss. Hence the values of A a are the 

 same as those of w and w -f- w', with changed signs. 



1830. Argelander's A. R. is given by Wolfers in his Tabular Reduc- 

 tionum, p. liii. I have no other knowledge about it save that it is 

 manifestly very accurate. 



1832. — Pond. I have preferred to employ the observations as 

 given in the annual catalogues from 1829 to 1835, instead of the result 

 of the catalogue for 1830. There is no appreciable difference of re- 

 sults ; but there is some obscurity as to the reduction of the earlier 

 observations. The result given for 1825 (1817-26) is (corrected for 

 nutation) 0^ 58'" 15\83, which accords well enough with Bessel's 

 value, 0*^ 58" 15^49. 



1835. — S. Fernando. The mean of the results for 1834 and 1835, 

 of three observers, 



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