Theory of the Chemical Elements. 871 



relative weights of the atoms of the primary substances 

 are J 



Coronium . . n = 2, n* = 3*1748, 



Hydrogen . . n = 3, ?fi = 6*2403, 



Nebulinm . . n = 4, n* = 10*079, 



Protofluorine . rc = 5, m* = 14*620. 



It is usual to take the atomic weight of; oxygen as 16 ; so 



that hydrogen has an atomic weight 1*008. On this scale, 



we find : — 



Atomic weight of Coronium = *51282, 



Hydrogen = 1*008, 



„ „ Nebulium = 1*6281, 



„ „ Protofluorine = 2*3615. 



The atomic weight of coronium is approximately the value 

 assigned by Mendeleef to a hypothetical element. Nebulium 

 may be the element predicted with an atomic weight nearly 

 equal to 2. 



Compound Atoms. 



Helium. — The terrestrial element succeeding hydrogen is 

 helium, whose atomic weight, as given by the International 

 Committee for the present year, is 3*99. 



A<>ain neglecting the weight of the electrons, we find by 

 addition that the weight of an atom consisting of one atom 

 of nebulium and one of protofluorine is 3'9896 or 3*99. 



Helium can therefore be expressed as a simple type of 

 compound atom. With the symbols Cn for coronium, Nu 

 for nebulium, and Pf for protofluorine, we may write 



He = Nu + Pf, 



where the equation is not to be interpreted in the chemical 

 sense. 



Before considering other elements, we must take account 

 of the inertia of the electrons. An estimate of its magnitude 

 may be obtained by the supposition that they are moving 

 slowly. It may be shown by a consideration of the spectral 

 lines that the velocity of the electrons in an atom of nebulium 

 is about *004 C, where C is the velocity of light. The nature 

 of the inertia-formula is such that this can be effectively 

 treated as slow, in the computation of a small effect of this 

 kind. 



Now the mass of a slowly-moving electron is 6. 10 -2S gram, 

 and the mass of a hvdrogen atom is 1*1 , 10 ~ 24 gram, according 



3 M2 



