162 THE LAWS OF 



(1 _ nf?\ 2 I X 



V X " I I 



,.3t+l+n 'Oft ^,2\2 



2.4.6 ...... 2s 



- 



/f ' ( } 



v 2 



since r(i)=V*r, Bin 



and as was before observed, x - . 



a 



But we have evidently by means of the binomial theorem, 



a V V-? _ v n - 2 .n.n + 2 



2.4.6 



and therefore the preceding quantity becomes 



rcc 

 If now we make x = , the same quantity may be written 



Having thus the value of the repulsion due to the inner 

 sphere B on an exterior point />, it remains to determine that 

 due to the fluid on A's surface. But this last is represented by 



l-n.3-n dr 



,_ 



(Mec. Gel. Liv. n. No. 12.) Now by expanding this function 

 there results 



