372 HEPoax— 18;2. 



The equations are solved by the method of least squares — thatis, the values 

 of ^^ are multiplied by the respective values of co? (o-— ra-)<, sin (ir— ro-)C, 

 cos 2at, sin 2(Tt, &c., and the products added together. The left-hand compo- 

 nents of ten equations are thus formed. The right-hand components -wiU. bo 

 constant for each year — that is, on the assumption that the value of nt is C^-O 

 at the commencement of the year. The following formulai have been calcu- 

 lated, giving the values of the coefficients for the right-hand components of 

 the equations on the above assumption : — • 



