( 559 ) 



00 00 00 



Cz ,Jx = 1 , Czx d.r = 11^ — & , (z.c' ,U = M, = ^1^' 



o o o 



Cz.v' J.V = f«, etc. ; ( Y.v <iv —O (6) 



ü II 



For the determination of the constants of form. (4) we tiien have 

 the four relations: 



C l.SU H 



A A 1 = 



2C 2AE 

 A -\ 1- = IP u, 



3C 3.5 E 2IIhi, l ' ' ' ' ^ ' 

 ^ 2H' ^ 4H' \/:x l 



^ IW ^ 4IP ' ' 



MiiUiplviiiu,- rcsp. bv 1, — 3, -f 3 and — 1 and achUng, we tind : 



or, because : 





1 1 1 



Ml = 7777—' f^5 = TTTT' ^> = 



//' SIP -611 



\ 1 = (8) 



From tliis equation possible values for H can be derived, but not 

 in an advantageous manner as the quantities h, h' and h" generally 

 are only slightly different. 



In practice, i. e. if we come to expression (4) by expansion of a 

 theoretical formula, the proitlem will prol>ably be less difficult, as 

 the constants H and A or H and h will not be independent of each 

 other, and it will be possible to reduce the four equations (7) to three 

 or two. 



In this preliminary investigation we conline ourselves to the most 

 simple case that H = h which, as it will appear, leads to satisfactory 

 results. 



Putting 



h—h' 



-ir = ''' 



we find : 



39 



Proceedings Royal Acad. Amsterdam. Vul. VIII. 



