KONINKLIJKE AKADEMIE VAN WETENSCnAPPEN 

 TE AMSTERDAM. 



TRUCEEDINGS OF THE MEETING 

 of Saturday April 22tb 1899. 



(Translated from: Verslag van do gewone vergadering der Wis- en Naliuirkundigc 

 Afdccling vau Zaterdag 25 Maart 1S99 Dl. VII). 



Contexts: -'On reducible Iiyperclliptic Integrals." By l'rof. J. C. Klcyvf.r, p. 440. — „Meitin;; 

 points in systems ot' optie isomers." By Prof. H. W. Bakiiuis Roozeeoo.v, p. 4C6. — 

 ,,0u the deduction of tlie characteristic cijuation." By Prof. J. D. vas der Waals — 

 discussion with Prof. Boltz.makn. p. 468. — „The galvano-magnetic and thermo-mag- 

 netic phenomena in bismuth (2nd Communication continued)." By Dr. E. tan Eveii- 

 DiNCEN Jk. (Communicated by Prof. II. Kameslixgu Osnes). p. 473. 



The fullowing papers were read : 



Mathematics. — "Ü« reducible lnjperelliptic litU'(jntJs\ By 

 I'rof. J. C. Kluyver. 



(üejïd in the Meeting of March 25"' ISOO). 



In some cases an Abelian integral of the first kind and of defi- 

 ciency p can be reduced to an elliptic integral. According to a 

 theorem of Weierstrass ^) when such a reducible integral presents 

 itself, it is possible to transform bv a substitution of order r the 

 (!>-function of the first order into an other one of order r, so 

 that the p — 1 constituents r'j^, r'jy, .... r'l^, in the first row of the 

 period matrix all assume the value zero. If, conversely, it is 

 possible by a substitution of order /■ to find a «9 -function whose 

 period matrix shows this peculiarity, at least one of the integrals 



') KowALEVSKi, Jcla Matli. IV, p. 395. 



• 31 



Procecdiugs Rojal Acad. Amsterdam. Vol. I. 



