XII CONTENTS. 



Physics. J. D. van dbr Waals: "Some observations on the course of the molecular 

 transformation", 303. 



— J, D. VAN DER Waals: "Critical phenomena in partially miscible liquids". Ï07. 



— J. K. A. Wertheim Salomonson: "The influence of variation of the constant 

 current on the pitch of the singing arc". 311. 



— J, E. Verschafpelt : "Contributions to the knowledge of van der waals ijcsur- 

 face. VII. The equation of state and the vj/-surface in the immediate neighbour- 

 hood of the critical state for binary mixtures with a small proportion of one of 

 the components." 321. 336. 



— L. H. Siertsema: "The calculation - from the magnetic rotation of the plane 



«i 



of polarisation, for substances without an absorptionband in the visible spectrum". 

 413. 



— J. J. Hallo: "The value of some magneto-optic constants". 438. 



— D. J. KoRTEWEG: "Plaitpoints and corresponding plaits in the neighbourhood of 

 the sides of the »J/-surface of van der waals". 445. 



— A. H. SiRKS : "Some remarkable phenomena, concerning the electric circuit 

 in electrolytes". 465. 



— J. P. KuENEN: "Critical phenomena of partially miscible liquids-Ethane and Me- 

 thylalcohol". 473. 



— J. D. van der Waals Jr.: "The variability with the density of the quantity b 

 of the equation of state". 487. 



— H. Kamerlingh Onnes : "Methods and apparatus used in the Cryogenic Laboratory: 

 HI. Baths of very uniform and constant low temperatures in the cryostat. 502. G28. 

 A cryostat of modified form for apparatus of small dimensions. 628. IV. A permanent 

 bath of liquid nitrogen at ordinary and at reduced pressure. 631. V. Arrangement 

 of a Bürckhardt-Weiss vacuumpump for use in the circulations for low tem- 

 peratures. 633. 



— J. J. VAN Laar : "On the course of the values of 6 for hydrogen, in con- 

 nection with a recent formula of Prof, van der Waals". 573. 



— W. H. Julius: "Peculiarities and changes of FRAUNHOFER-lines interpreted as 

 consequences of anomalous dispersion of sunlight in the corona." 589. 



— H. A. LoRENTZ : "Contributions to the theory of electrons." (I). 60S. 



— H. Kamerlingh Onnes and H. II. Erancis Hyndman: "Isotherms of diatomic 

 gases and their binary mixtures. V. An accurate volumenometer and mixing 

 apparatus." 636. 



— W. H. Julius : "On maxima and minima of intensity sometimes observed within 

 the shading of strongly widened spectral lines." 662. 



— H. A, Lorentz : "On the emission and absorption by metals of rays of heat of 

 great wave-lengths." 666. 



Physiology. J, W. Langelaan : "The principle of entropy in physiology." II). 57. 



