676 



SCIENCE PROGRESS 



C : H =4:1, which is at the bottom of the valency rule met with 

 in the Hydrocarbons. 



The change in structure involved in passing from Hexane, 

 C G Hi4, to Benzene, CcHc, does not prejudice the relation men- 

 tioned. 



The explanation of this on the basis of a co-volume or 

 molecular vibration volume is not apparent. 



The Law of Additivity in the Simple Normal Paraffins, etc., 

 at Corresponding Pressures 



The ratios ^ give the volumes of one valency or the atom of 



combined Hydrogen under the different conditions. The volume 

 of combined Carbon is four times this value. Such differences 

 as we find are due to differences in constitution. 



The accurate investigation of molecular volumes is thus 

 greatly facilitated by a recognition of the Law of Constant 

 Volume Ratios : 



The Additive Rule in the Complex n-Paraffins near the 



Melting Point 



The atomic volumes are practically constant under the cir- 

 cumstances. 



