{-) I y 



Figure 237 — Diagram for translation of an 



oblate spheroid parallel to an equatorial 



axis. Dots indicate traces of a focal 



circle. See Section 138, Case 3. 



The components of velocity in the coordinate directions are, from Equations [I38r, s, t], 

 ,2\l/2 / ^2^2 



g^=h^V 



1-11^ 



C^i^' \C' + i 



■ L, cot (^ cos o), 



[138z'] 



?. =^^/^(^ cot-i^- 



C^+M- 



q,-h,V cot-^C- 



e^i 



cos OJ, 



e^\ 



[138a"] 



[138b' 



On the y-axis and on the 2a;-plane the velocity is in the direction of i F and q - \v\. On the 

 y-axis cos a> = i 1, ;i = 0, y = ± k{(^^\)^''^, <C = {y'^/k^ -l)^'"^ , and 



?^=/»2 



h„V 



k{y^ + k^) . _i k 

 /. -sin 77 



[138c- 



365 



