798 
MR. G. H. DARWIN ON THE SECULAR CHANGES IN 
Terms depending on y. 
Here 
S=—yz, u——yy, <j— 0, v = 0 
s= +a y) s = 
a )yi =- y%i 
S 2 , 2o have similar forms with 2 for 1 
Obviously 
( ,c i 2+ l>) Si=0 
a K i + n 
Si— ^ % 1 — 2yK 1 y 1 . . . 
Hence the equation for z is 
1 
D%= 2 K 1 (/c 1 + «- 2 )(/c i + a)y 1 + the same with 2 for 1 
Therefore 
1 
-2 1 
I> 
-A 
II 
And 
/ 1 dL-^S. "h 
\-^l dt jy ^ K± Kg 
Again 
fc 2 +Cl , K-i + X 
-+ %—- 
K-z) K zf K ^ 
*i-*a 
*.‘+|) 2 i =0 
^1 
/i+/3 q __b 
Sr 
/Cj + « 
«2 + /Sl 
i 2 *i 
=b >W* 
b 
And the equation for £ is 
1 
Therefore 
7 b 
D 4 £= 2 k 1 (k 1 +Ko)y].+ the same with 2 for 1 
— A£ = ——-] -2»_ 
<ybt y k 1 — k 2 k s — k x 
£i Kg + St £ 3 ^ __^^2 + a _ _ y Kj+a 
b K 1 — Kg b Ky—Kg 
, since 2 1 =£ 1 - s t—, 2 S = &- 
(215) 
