364 



Prof. G. H. Darwin. On an Apparatus for [Dec. 15, 



Rule for finding semi-annual inequality from an incomplete series. 



Number of 

 months 

 available. Coefft. of Z> . Coefft. of 



6 Ao = +0167 



A 2 = 



+ 0-333 



Coefft. of Z> 2 . 



+ 0-333 



