KONINKLIJKE AKADEMIE VAN WETENSCHAPPEN 
TE AMSTERDAM. 
PROCEEDINGS 
VOLUME XIX 
N°. 5. 
President: Prof. H. A. LORENTZ. 
Secretary: Prof. P. ZEEMAN. 
(Translated from: “Verslag van de gewone vergaderingen der Wis- en 
Natuurkundige Afdeeling,’ Vol. XXV). 
CONTENTS. 
A. H. W. ATEN: “On some Particular Cases of Current Potential Lines”. IL. (Communicated by Prof. 
A. F. HOLLEMAN), p. 768. 
C. OTTO ROELOFS: “An exact method for the determination of the position of the eyes at distur- 
bances of motion.” (Communicated by Prof. G. VAN RIJNBERK), p. 778. ° 
J. C. KLUYVER: “The primitive divisor of x/’—1”, p. 785. 
C. H. H. SPRONCK and MiSs WILHELMINA HAMBURGER: “On passive immunisation against tetanus.” 
p. 789. 
F. E. C. SCHEFFER: “On the Allotropy of the Ammonium Halides.” III. (Communicated by Prof. P. 
ZEEMAN), p. 798. 
J. A. HONING: “Variability of segregation in the hybrid.” (Communicated by Prof. F. A.F.C. WENT), 
p. 805. 
F. A. H. SCHREINEMAKERS: “In-, mono- and divariant equilibria.” XII, p. 816. 
49 
Proceedings Royal Acad. Amsterdam. Vol. XIX. 
