872 Dr. J. W. Nicholson on a Structural 



to the best estimates. The fraction of the weight of the atom 

 due to its three electrons is therefore practically 1* 67. 10~ 3 , and 

 therefore, if 1*008 be the atomic weight, the weight of the 

 corresponding nucleus is only 



(1-008)(1- -00167). 



The revised weights of the nuclei of the other simple atoms 

 become therefore 



Cn =■ '51196, Nu = 1-6251, Pf = 2-3576. 



Adding the weights of the electrons in each case, on the 

 appropriate scale -00056 for each electron, we have the 

 following results : — 



Atomic weight of Coronium = '5131, 



„ „ Hydrogen = 1*008, 



„ „ Nebulium = 1-6277, 



,, „ Protofluorine = 2*3601, 



the alterations affecting only the third decimal place slightly. 



The atomic weight of helium now becomes 3*9881, or 

 again 3*99. 



It may be shown that this value persists even if the 

 electrons move so fast as to double their inertia. This would 

 approximately be the case if the velocity of an electron were 

 4/5 of that of light. 



We proceed to the consideration of other simple cases 

 before attempting to construct a general scheme. When the 

 helium group enters, it is not implied that this group is always 

 intended rather than its two component groups, which may 

 be differently situated in the atom. 



There is a fairly general suspicion that many of the 

 elements may be composed of helium and hydrogen. This 

 view receives some support from the following consi- 

 derations. 



In constructing the elements, coronium is not used. This 

 reduces the number of primary substances to three. The 

 possibility of fortuitous equalities of numbers is thereby 

 greatly reduced. Coronium must be retained as a substance, 

 but it does not seem to have a necessary function in the 

 construction of others, being, like the possible primary sub- 

 stances with six and more electrons, rather a hindrance 

 when the attempt is made to construct the simpler compound 

 elements (with the exception of lithium, a doubtful case) by 

 its combinations with others. It is possible that it is con- 

 cerned iu the composition of the very rare elements, such as 



