216 Mr POWER'S THEORY OF 



The residual force is therefore 



I {s,-s,){2{H)-^{K)-2{L) + 2{N)} 



2 



+ l-{s,'-s.'){2{L)-{M)-{N)}. 



Again, r = r^+p, = {r).^^+{p).■^ 



= ('•) *! + (/») (1-*.); 

 (p)-r 



••. *, 



=={r)s, + {p).{l-s,); 



■• '~ip)-irr 



_ p — r 

 ip) - {r) 



„ . „_?ie)zik±rl. 



i_^ 



{ip)-ir)r {{p)-ir)r' 

 The expression for the residual force is, therefore, 



p^ -r 



i-fvFW*'<'^>-''^>-<'^>'' 



