CONTENTS. XIX 



Physics. W. H. Keesom : "Isotliennals of mixtures of oxygen niul carhoii dioxide. T. The 

 calibratiou uf inaiiouieter and piezometer tubes. 503. 11. Tbe preparation of tlie 

 mixtures and tlie compressibility at small densities. 541. III. The determination 

 of isothermals between 60 and 140 atmospheres, and between — 15° C. and 

 -|- 60° C. 554. IV. Isothermals of pure carbon dioxide between 25° C. and 00° 

 C. and between 60 and 140 atmospheres." 565. V. Isothermals of mixtures of 

 tlie molecular compositions 0.1047 and 0.1994 of oxygen, and the comparison of 

 tbera with those of pure carbon dioxide. 577. VI. Influence of gravitation on the 

 phenomena in the neighbourhood of the plaitpoint for binary mixtures." 593. 



— H. E. J. G. DÜ Bois : "Hysteretic orientatic-phenomena." 597- 



— H. Kameulingh Onnes and C. A. Crommelin : "On the measurement of very 

 low temperatures. VI. Improvements of the protected thermoelements; a battery 

 of standard-thermoelements and its use for thermoelectric determinations of tem- 

 perature." 642. 



— H. Kameulingh Onnes : ''Methods an<l apparatus used in the cryogenic Labo- 

 ratory. VI. The methylchloride circulation." 668. 



— H. KAMERLfNGH Onnes and B. Happel : "The representation of the continuity 

 of the liquid and gaseous conditions on the one hand and the various solid 

 aggregations on the other by the entropy- volume-energy surface of Gtbbs." 678. 



— L. H. Siertsema : "Investigation of a source of errors in measurements of 

 magnetic rotations of the plane of polarisation in absorbing solutions." 760. 



— Ph. Kohnstamm : "On the equations of Clausius and van der Waals for the 

 mean length of path and the number of collisions." 787. 



— Ph. Kohnstamm : "On van der Waals' equation of state." 794. 



— Miss J. Eeudler : "Note on Sydney Young's law of distillation." 807. 



— H. A. LoKENTZ : "Electromagnetic phenomena in a system moving with any 

 velocity smaller than that of light." 809. 



Physiology. M. C. Dekhuyzen and P. Vermaat : "On the epithelium of the surface 

 of the stomach." 30. 



— E. Hekma : "On the liberation of trypsin from trypsin-zymogen." 34. 



— J. K. A. Wertheim Salomonson : "A new law concerning the relation between 

 stimulus and eflect" (Q^^ communication). 73. 



•^ A. Gorter : "The cause of sleep." 86. 



■^ W. EtNTHOVËN : "The string galvanometer and the human electrocardiogram." 10?. 



— J. Bo EKE : "On the development of the myocard in Teleosts." 218. 



**- Gi VAN Eijnberk : "On the fact of sensible skin-areas dying away in a centri- 

 petal direction," 846. 



— C. Winkler and G. van Rijnberk : "Structure and function of the trunk- 

 dermatoma." IV. 347. 



— C. Winkler and G. van Eijnberk : "Something concerning the growth of the 

 lateral areas of the trunk-dermatomata on the caudal portion of the upper 

 extremity." 392. 



— J. K. A. Wertheim Salomonson : "On tactual after-images." 481. 



— W. EiNïUovEN: "On some applications of the string-galvanometer." 707. 



