94 Dr. R. D. Kleeman : Determinations of the Law of 

 not the case ; as is shown by Table II. The expression 



is therefore a function of the distance between the molecules 

 as well as of the temperature. 











Table II. 

















Benzene. 



Chlorobenzene. 



Carbon 

 tetrachloride. 



Methyl 

 formate. 



T 



353 



433 



503 



423 



473 



533 



363 



433 



503 



303 



363 



423 





L 



85-6 



69'7 



50-5 



65-8 



583 



49-1 



40-6 



33-3 



237 



107 



85-1 



64-0 

 135 





. , 4/3 4'3x 



Mpi — Pa ) 



L (pl -Pi) 



! 



•273 



•210 



•140 



•279 



•243 



•184 



•341 



•270 



•171 



•223 



•190 



If it could be proved that the above function consists of 

 two factors, one a function of the temperature and the other 

 of the distance between the molecules, say 



z T 

 then the form of both 



HJ'5\)=K£)* 4 (t;) 



4,(0 and &(J) 



could be completely determined. The formulae for the latent 

 heat and surface-tension then become 



where <f> 5 and <£ c are known functions of 



(T \ T r/>* 



,-pr) we obtain the equation - = j£, which 

 i c / 7 9e 



can be used to determine approximately the form of the 



function </> 3 / ^ J by taking a sufficiently large number oi 

 equations corresponding to different values of p. The form 



