MR. G. H. DARWIN - ON THE SECULAR CHANGES IN 
796. 
Then (by (192)) writing for k 3 +A k 1 -\-/3; — (fq-J-a) and — (/Co + a) respectively, we 
have by symmetry with (206), 
Terms depending on the variation of a. 
We now put for a in (181) a+a 't. 
Then in (194) 
S = &'tr), u— —a 'tf <7=0, v=0 
Therefore 
So, have similar forms with 2 for 1 
^i—^ J ^^i=^lVi+ t U( K i— a ) + tC(K 1 -\-a)]=a,'[r) l ~\-2K l tC l ] . . . (209) 
Hence the equation for 2 is 
1 
fCj + Cl K„-\- Cl 
K^ + U 
b 
