XIV CONTENTS. 



Physics. H. Kamerlingh Onnks and C. Bkaak : "On the measurement of very low 

 temperatures. XVIII. The determination of the absolute zero acoordins^ to the 

 hydrogen thermometer of constant volume and the reduction of the readings on 

 the normal hydrogen thermometer to the absolute scale". 429. 



— P. Zeeman : "Observations of the magnetic resolution of spectral lines by means 

 of the method of Fabry and Perot". 440. 



— H. Kamerltnqh Onnes: "Isotherms of monatomic gases and their binary mixtures. 

 1. Isotherms of helium between + 100° C. and —217° C 445. II. Isotherms 

 of helium at —253° C. and —259° C. 741. 



— P. Zeeman : "New observations concerning asymmetrical triplets". 566. 



— P. Zeeman ; "Change of wavelength of the middle line of triplets". 574. 2nd 

 part. 862. 



H. E. J. G DU Bois and G. J. Elias : "The influence of temperature and 



magnetisation on selective absorption spectra". 578. II. 734. III. 839. 



— H. Kamerlingh Onnes : "On the measurement of very low temperatures. XIX. 

 Derivation of the pressure coefficient of helium for the international helium 

 thermometer and the reduction of the readings on the helium thermometer to 

 the absolute scale". 589. 



— Jean Becquerel and H. Kamerlingh Onnes : "The absorption spectra of the 

 compounds of the rare earths at the temperatures obtainable with liquid hydrogen, 

 and their change by the magnetic field". 592. 



— H. Kamerlingh Onnes and W. H. Keesom : "On the equation of state of a 

 substance in the neighbourhood of the critical point liquid-gas. I. The disturbance 

 function in the neighbourhood of the critical state. 603. II. Spectrophotometrical 

 investigation of the opalescence of a substance in the neighbourhood of the critical 

 state". 611. 



— H. E. J. G. DU Bois, G. J. Elias and E. Lowe: "A.u auto coUimating spectral 

 apparatus of great-luminous intensity". 729. 



— H. Kamerlingh Onnes and C. Braak: "On the measurement of very low tem- 

 peratures. XX. Influence of the deviations from the law of Boyle-Charlesou the 

 temperature measured on the scale of the gas-thermometer of constant volume 

 according to observations with this apparatus". 743. 



— H. Kamerlingh Onnes : "On the condensation of helium". 744. 



— H. Kamerlingh Onnes : "Experiments on the condensation of helium by 

 expansion". 744. 



J. D. VAN DEE Waals Jr.: "The value of the self-induction according to the 



electron-theory". 850. 

 Physiology. L. J. J. Muskens: "Nerve influence on the action of the heart. 1st Com- 

 munication. Genesis of the alternating piilse". 78. 



— Y^ . EiNTHOVEN : "On a third heart sound". 93. 



H. Zw^AARDEMAKER : "On the adsorption of the smell of muscon by surfaces of 



difterent material". 116. Continued. 120. 



— H. J. Hamburger and E. Hekma : "Ouantitative researches on Phagocytosis. 

 A contribution to the biology of phagocytes". 144. 



