On Material Molecules and, the Etherial Medium. 265 
Differentiating equations (23) we get 

v a sm 
= - 
&c. 
do? 
Hence substituting in any of the equations (21) we 
have ^ 
v'u = A(/2 + m2 + 7^2) + P^2^^ - P^2'^^' 
= { ^ (^'^'' + B'^'' + C5^^'') -- } ^' • • (24) 
Similarly from equations (22) 
I ^'2 _ (Y'P + + HV2) - P'^2 } 
Multiply the right and left hand sides respectively of (24) 
and (25), and divide by uu\ and we have 
(^^2 _ ^ _ p^^^ I ^^2 _ (^^7^2 ^ Gl^^,/2 + H V2) - P'^ I 
= " { "^'^'^ + + - } 
Let us neglect the terms containing and X'^, which are 
