( 323 ) 



Physics. — ^On a simplified theory of the electrical and optical 

 phenomena in moving bodies". By Prof. H. A. Lorentz. 



(Will be published in the Proceedings of the next meeting). 



Physics. — „Stokes' aberration theory presupposiny an ether of 

 inequal density''. By Prof. 11. A. Lorentz. 



(Will be published in the Proceedings of the next meeting). 



Physics. — „Measurements on the system of isothermal lines near 

 the plaitpoint, and especially on the process of the retrograde 

 condensation of a tuixtnre of carbonic acid and hydrogen^'. 

 By Dr. J. Verschaffelt. (Continued). (Communication n". 47 

 from the Physical Laboratory at Leiden by Prof. H. Kamer 



LINGH ONiNES). 



§ 5, The course of the plaitpoint curve. 



Two other mixtures *• = 0,0995 and ir = 0,1990 were investigated 

 in the w^ay described in § 2. But in the case of these two 

 mixtures the investigation could not be made so completely as in 

 the case of the first mixture. For * = 0,0494 we could trace the 

 isothermals pretty far above the plaitpoint-pressure; but for .t = 0,0995 

 the plaitpoint was situated towards the end of the series of observations, 

 and for a- = 0,1990 the observations could only be made till near 

 the critical point of contact. B\' means of these observations, the 

 results of which are communicated in the tables III and IV, we 

 can derive some information regarding the course of the plaitpoint 

 curve in mixtures of hydrogen and carbonic acid in the neighbour- 

 hood of pure carbonic acid. 



22=* 



