XIV CONTENTS. 



by means of liquid hydrogen. 156. XL The purification of hydrogen for the 

 cycle. 171. XII. Oyo9tat especially for temperatures from — 252° to — 259°. 

 173. XIII. The preparation of liquid air by means of the cascade process. 177. 

 XIV. Preparation of pure hydrogen through distillation of less pure hydrogen". 179. 

 Physics. H. Kamerlingh Onnes and C. A. Crommelin : "On the measurement of 

 very low temperatures. IX. Comparison of a thermo-element constantin-steel with 

 the hydrogen thermometer". 180. Supplement. 403. 



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

 peratures. X. Coefficient of expansion of Jena glass and of platinum between 

 -|- 16° and — 182°. 199. XI. A comparison of the platinum resistance thermo- 

 meter with the hydrogen thermometer. 207. XII. Comparison of the platinum 

 resistance thermometer with the gold resistance thermometer." 213. 



— . W. H. Julius: "Arbitrary distribution of light in dispersion bands, and its 



bearing on spectroscopy and astrophysics". 343. 

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



temperatures. XIII. Determinations with the hydrogen thermometer". 367. 



— E. E. Mogendorfe : -'On a new empiric spectral formula". 434. 



II. Kameklingh Onnes : "Contributions to the knowledge of the ^-surface of 



van der Waals. XI. A gas that sinks in a liquid.'* 459. 



— 0. Postma :' "Some additional remarks on the quantity 11 and Maxwell's distri- 

 bution of velocities." 492. 



H. Kamerlingh Onnes and W. II. Keesom : "Contributions to the knowledge 



of the vjz-surface of van der Waals. XII. On the gas phase sinking in the 

 liquid phase for binary mixtures". 591. 



— W. H. Keesom : "Contribution to the knowledge of the ^-surface of van der 

 Waals. XIII. On the conditions for the sinking and again rising of the gas 

 phase for binary mixtures." 508. Continued. 660. 



— J. D. van der Waals : "A remark on the theory of the ^-surface for binary 

 mixtures." 524. 



— W. J. H. Moll: "An investigation of some ultra-red metallic spectra" 544. 

 J. 1). van der Waals: "Contribution to the theory of binary mixtures." 621. 



II. 727. HI. 826. 



— Ph. Kohnstamm : "On the shape of the three-phase line solid-liquid-vapour 



for a binary mixture". 639. 

 p H . Kohnstamm: "On metastable and unstable equilibria solid-fluid." 648. 



— H. Kamerlingh Onnes and Miss T. C. Jolles: "Contributions to the know- 

 ledge of the J,-surface of van der Waals. XIV. Graphical deduction of the 

 results of Kuenen's experiments on mixtures of ethane and nitrous oxide." 664. 



— W. H. Julius: "Wave-lengths of formerly observed emission and absorption 

 bands in the infra-red spectrum." 706. 



— C. II. Wind: "A hypothesis relating to the origin of Röntgen-rays." 714. 



— J. H. Meerburu: 'On the motion of a metal wire through a piece of ice." 7 18. 

 J. D. van der Waals : "The shape of the empiric isotherm for the condensation 



of a biuarv mixture." 750. 



