( 60 ) 
ib je (aar f' + az g' + Azz h’') — nl (dyx f! + Ayy g + ayz hy, : 
s 
v A / | 
bash (daz f! + ary g Haa kh) — Vac f' + azy 9 + azz h) ‘ 
v F ; 
c= 7 l' (dyx f =p yy g' as Qyz h') = ae (azz f' + Oxy gj -{- Axrz 1) ’ 
! 
where s"=————=. From these equations everything has disap- 
V le My Uz 
peared that depended on the special choice of axes of the coordinates ; 
they are therefore of general application, and they will still hold if 
we choose the axes of the transformed electric ellipsoid as axes of 
the coordinates Os which the equation of the ellipsoid becomes : 
aat? +- ayy 4+ a, 22 =1. The last three equations become then: 
a = (m'azh—nag), . - . = - GH 
=n anf! — aye ee 
cS (lag afde >. . 
$8 
If we eliminate a', b' and ec, we find: 
f' (aq vt — 8!) =v? Vag f' +a, m'gi +aznh), . « (90) 
g (ay? — 8") =v? mi! (ag Uf’ + ay m'g' Haen kh), « « (BH) 
h! (az v2 — 3!) = vo nl (ar lf’ Hay ne! gl Harn! hl). . . (82) 
l 
Multiplying (50) by ——,, (61) by en andes 
Ay ve — ay v— 8 
nl : 
by ———;, and adding them, we find: 
Oe 
['2 m'? n'? 
a, 9 + 1 = 0. 2 6 (53) 
dy ves? ls? aus? 
