Atomic Volumes and the Spectra of Elements. 925 



trunk series, so that the latter also is indirectly connected 

 in some way with the above atomic volumes' law. 



It was next tried to find a law connecting the two con- 

 stants A and B. The larger A, the larger is B, but they 

 cannot be connected by any simple mathematical relation. 

 B seems to be increasing by a definite amount as we pass 

 from group to group. For if we draw some parallel equi- 

 distant lines representing the different families of elements 

 (corresponding to the vertical columns of MendeleefFs tables) 

 and plot on these the values of B, we find that the points thus 

 obtained lie near two parallel lines (fig. 2). 



In conclusion, the constant a of Ritz's formula can be 

 expressed as a function of the atomic volume, so that whether 

 these fields of magnetic force are due to elementary magnets, 

 or as imagined by Ritz to solids of revolution charged with 

 electricity at their surface and in rapid rotation round their 

 axis, there seems to be a connexion between their dimensions 

 or configurations and the volume of the atom containing 

 them. 



Manchester University, 

 October 1911. 



