W. A. Norton— Variability of the Ultimate Molecule. 198 
from the luminiferous ether. If, then, there be an electric ether 
distinct from the luminiferous and presumably less subtile (i. e. 
made up of larger atoms) the ethereal atmosphere condensed 
around an atom by its attractive action, should consist of an 
atmosphere of luminiferous ether and an envelope of electric ether | 
immersed within this fora certain depth. Such is the definite 
conception I have adopted of the constitution of the molecular 
atmosphere. It may be characterized as an ethereo-electric 
atmosphere. From this combined with the fundamental 
hypothesis that recurring impulses are incessantly exerted on 
one another, by all the atoms, ethereal and non-ethereal, that 
make up the ultimate molecule, I have deduced the operation 
of certain molecular forces. The two ethers condensed around 
this system of wave-actions may be combined with the attrac- 
tive system into resultant attractive actions. The different 
