G. PLARR ON THE SOLUTION OF THE EQUATION Vp¢p=0 71 
Q h,\? 
‘i =(-#) 
Q 
=), =72 
Calul of W,, by bis Sree 
Q,= —het+Q=—h(é +h) 
=—h,|(h,—h,)(h,—h, +h] 
=—h, [hh,—h-hh,+hh,+hh,] 
=—h*{h—h, +h,|=—h*(—2h,) 
= h*; therefore 
W.=h, 
Also wi=2—5(— Ee, + Y’)= ae px +Q 
Te" 730\ 
8p s — — (5p 

3 3 3 
GSW )x = ahh (E—W), = UP ) (E—W), = 5h; 
‘ 3 
(E—W), = + (=p) | (E-W),=5h. 
—W) =(“-) | @-W),- 
Gy Phra): 
§ 11. We will now, for preparing the construction of the surface [=0, 
ascertain for the five values of E, =h;, 0, E,, h,, h,, the corresponding 
values and direction of 
YN 
e, v, de, dH, igev. 
In the case h, >0, the values of E are in the following order : 
h;<0 <a 
In the case of h, <0, the order is: 
Ia<hg< Ei <0<h,, 
but we will, for the present, consider the case /,> 0 exclusively. 
