]^2 Art. 3..— K. Hirayama : 



whence 



dB _ _ 1 nj dx 

 dt Sa iv dt 



Developing n and a in terms of powers of x and integrating 

 JR=--?1+ Const. 



in which oc' and liigher powers are neglected. Or 



X- 4- G^f^Bo + 6a-,>Bc = C oust . 



ii*o is a function of a and e^ and ê is a function of x containing an 

 arbitrary constant. Hence developing 



^»=W»H^lF+^f)/ 



+ 



where the suffix outside of the parentheses means the value for 

 ^^=0. The terms with o^ and higher powers may be neglected, 

 since they are multiplied by m . Now 



lda\__1 (dê\ _ 2 8- s' 



whence 



Substituting this expression in the integral we get 



or putting 



(10) .„=.«„=(^)^-2i^„„(^|^ 



the integral becomes 



(11) (.r-a-„)- + B«,.Rc=0 



