Tlie Theory of Molecular Volumes. 



439 



gas are practically all neutral and reach the electrodes 

 through diffusion. On this account the general process 

 becomes again the relatively simple one o£ electric convection 

 and diffusion, to which reference has previously been made. 



Under conditions which are such that the deposit atoms in 

 the gas no longer form aggregates nor are charged by means 

 of gas ions, their coefficient of diffusion through dry air at 

 one atmosphere pressure and at ordinary room temperature 

 (about 20° C.) is approximately *045 cm. 2 sec. -1 . 



Sloane Laboratory, 



Yale University, 

 17th June, 1914. 



LI. The Theory of Molecular Volumes. 

 By Gervaise Le Bas, B.Sc* 



Part IV. 



Completed Ring Systems and the Volxme Anomaly. 



Systems of Completed Rings. 



THE influence of Ring structure upon the magnitude of 

 most physical properties is usually not great — only a 

 small fraction of the whole. The more important properties 

 besides volume which are affected by this constitutive 

 feature are, Refractive Power and Magnetic Rotatory Power. 

 The extent of the influence exerted by Ring structure upon 

 these, is indicated by the following table. The columns 

 marked A represent the differences between the observed and 

 calculated values when all other constitutive influences have 

 been taken into consideration. 



lief, -active Power. 



Magnetic Rotatory Power. 



Compound. 



Paraldehyde .... 



Epichlorhydrin. 

 ■ Pipiridene 



Cyclopentanc... 



Cyclohexane .... 

 ; Cyclohexanone . 

 I Pinene , 



Camphene 



| Tricyclodecane . 



M"a(obs). 



A. 



324 



4-0-30 



20-47 



+0-19 ; 



2657 







2309 



+0-08 



27-62 



+0 05 



27-82 



+0-02 



43-72 



4-0-59 



4309 



4-0-56 



41-65 



4-035 



i 



Compound. 



Trimeth. CarboxylicAcid. 

 Tetraineth. Carb. Acid.... 

 Ethyl Cvclobutvl Ketone. 



M. 



4-141 

 5 048 

 6*911 



A. 



Cyclohexane 5'664 



Camphor 9 265 



Borneol 9-807 



-0331 

 -0-465 

 -0634 



-0982 

 2 x -0-645 

 2 x -0-636 



Communicated by Prof. W. J. Pope, F.E.S. 



