60 



then 



that is 



Mr. H. M. Macdonald. The JSencling of [May 12, 



and putting 

 then 



Now 

 whence 



therefore 

 hence 



or 



where 



Again 



a 



that is 



( 

 or 



c 



Further 



u n (z) 



cos ^ 



- 



da 



> 



t 

 *()coBXii 



ROT. Soc. Proe.,* vol. 71, p. 253. 



