314 



DIRECT PROPERTIES OF MOLECULES 



113 



The following table contains the results of the different 

 calculations of the molecular volumes : 



Molecular Volumes. 



Column I. gives the values of the volume of the sphere of 

 action, taken as spherical, on an arbitrary scale ; these were 

 calculated by Lothar Meyer from Graham's experi- 

 ments on transpiration. We must further remark that the 

 mean molecular weights of the components of air have been 

 employed for the calculation of the number given for air, 

 and also that the number for water- vapour, which I have 

 added, has been deduced from Kundt and Warburg's 

 experiments on viscosity. 



Column II. contains the values, calculated by Kopp's 

 rules, of the molecular volume in the liquid state. For the 

 volumes of an atom are taken 



S = 22-6 = 11-0 N= 2-3 



Cl = 22-8 H= 5-5 CN = 28-0, 



and it is assumed that = 7 -8 in free oxygen, water vapour, 

 and methyl ether, and = 12- 2 in carbon monoxide, nitric 

 oxide, and nitrous oxide ; further, that in carbonic acid and 

 sulphurous acid the two atoms together have the value 

 7-8 + 12-2 = 20-0. 



Column III. contains the values which result from 



