( 95) 



P\ = f'\ <-'" . Pi = f'2 «'' . 



and eliminate //j, //j, ■ • • /<<)i- If 



^ - *,2 ^ - i- 3 



'^1 ! "'S 1 



«1 flj 



Ph = iin e" 



— — "n • 



and 



the result may be put into the form 



«n.l ^ 



<'n.2 ^» t(i.3 ^ 



«l.n ^ 

 «2.n I 



= . (3) 



In consequence of the relation (2), the development of the deter- 

 minant will contain only even povFers of l-. Hence an equation is 

 obtained, of the «'•> degree in Z-. From the circumstances of the 

 case it follows, that the roots of this equation are all real and nega- 

 tive; hence n pairs of imaginary values of I are obtained. If + t^V 

 and — ik\. are two of those values, there will be a mode of vibra- 

 tion with the frequency (number of vibrations in the time 2 n) k',-. 



Evidently, without the field', the frequencies would become 



^'ii ^"ji 



«'n » 



and it is clear that, if there is a magnetic field, each of these 

 frequencies is modified into a value A-',., differing very slightly from l;-. 

 In the cited paper I had restricted the development of (3) to 

 terms containing the products of two factors e. Denoting by 11 the 

 product 



{I' + h') ii' + h') 



(i^ + h') 



and by llr.s the value, got from this by omitting the factors l^ -{- ,(>- 

 and l'^ -\- k^^y we obtain 



n-:El^ er.s es,- 11,. s = 0, 



(4) 



