20 Mr. W. Sutherland on a 



constitutive pairs of electrons to cohere in each chain. One 

 of the effects of: atomic disintegration must be the liberation 

 of one of these chains, which, when free, will behave in many 

 respects like the moving steel chain in gyroscopic experiments. 

 If a chain is broken into its separate electron pairs each will 

 form the pair which I have proposed to call a neutron, which 

 seems to be a necessary constituent of the luminiferous aether 

 to enable it to transmit electric and magnetic actions. 



Theoretically, then, there is reason to look for the free 

 pair of electrons as a physical agent as it appears in Bragg's 

 hypothesis for the gamma and the Rontgen rays. If Ruther- 

 ford's view of the alpha particle is correct, namely, that it is 

 an atom of helium carrying two positive electrons, I would 

 suggest for it the structure shown in the diagram, where a 



Fig. 2. 



b 



circular ring of electrons has collapsed into the form of two* 

 parallel cohering straight chains enclosing a positive electron 

 at each end. These by their repulsion tend to keep the 

 chains straight. If such a structure breaks away in the dis- 

 integration of radium with a velocity nearly that of light, it 

 will have many of the properties of an alpha particle. When 

 the two positive electrons are removed the structure re- 

 arranges itself in the form of the He atom. It ought to 

 throw much light upon the internal structure of the atom if 

 the reason is discovered for Bragg's remarkable law that the 

 stopping power of the atom of an element for the alpha 

 particle varies as the square root of the atomic mass. 



It should be noted that each pair of electrons may be 

 rotating round the average position of its electric axis, and 

 may thus have a magnetic moment parallel to the electric. 

 Each pair by virtue of its inertia has the properties of a 

 gyrostat. Each pair is a vibrating system whose period can 

 be calculated on the principles here discussed. The idea of 

 the electric gyrostat has already been used in a theory of 

 the electric conductivity of metals in " The Electric Origin 

 of Rigidity and Consequences." 



