APR E.] ORBIT OF ELECTRON 213 



It is shown on p. 760 of my 1885 B.A. Report on 

 Electrolysis, that a potential gradient of the order 1 volt 

 over molecular distance is sufficient to overcome atomic 

 attraction and effect decomposition in liquids. Any liquid 

 which is a conductor throws the whole applied stress on 

 to a molecular layer contiguous to an electrode, and accord- 

 ingly something of the order of a volt or two difference 

 of potential between electrodes in such a liquid is required, 

 and is sufficient, for decomposition. 



APPENDIX F. 

 Size of Orbit of Radiating Electron. 



Consider two electrons of opposite sign revolving round 

 each other with luminous frequency n at any distance r\ 

 or better, consider a free negative electron revolving round 

 a comparatively fixed equal positive charge attached to an 

 atom, at distance r. 



The force between them is e 2 //cr 2 , so the acceleration is 



But the acceleration is also expressible as 47rVr. There- 

 fore 



which is " Kepler's third law " for the case, and indicates 

 that the distance at which luminous frequency is attain- 

 able is the atomic distance 10 ~ 8 centimetre; in other 

 words, that the electron is roaming over the surface 

 of the atom. If it got nearer to the centre of force 

 than this, without penetrating any of the attracting sub- 

 stance, it would have to revolve quicker ; and such rapid 



