250 



PROCEEDINGS OF THE AMERICAN ACADEMY 



1850 Greenwich 

 1860 Paris 

 1860 Greenwich 



No considerable correction seems necessary. 



Table II. gives, for the years 1815-1860 inclusive, that part of the 

 correction for the error of Lindenau's nutation, which is not eliminated 

 in the clock-error. In applying it I have been careful to use the mean 

 of the values taken from it for the years of observation, which some- 

 times extend over a large part of one revolution of the node. For 

 this reason the number in the column A v opposite any given date in 

 Table I. is not usually the result of Table II. for that year. 



TABLE I. — Comparison of Computed and Observed Right Ascen- 

 sions of Polaris. 



