THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[SIXTH 8BRIB5 



lU 4 ^/ 



AUGUST 191V/V 1 9f?< 



VII. Astronomical Consequences of the Electrical lReory of 

 Matter. By Sir Oliver Lodge*. 



THE inertia of an electric charge was predicted by 

 Sir J. J. Thomson in 1881 ; the dependence oi electric 

 inertia on speed of motion through the aether was calculated 

 by Oliver Heaviside in 1889, and confirmed by Thomson, 

 who also isolated the unit charge in 1899 ; while the expe- 

 rimental verification of inertia as a function of velocity, by 

 Kaufmann, occurred in 1902. 



On the electrical theory of matter a body of any material 

 moving at high speed through the aether acquires extra or 

 spurious or apparent inertia ; and this inertia is presumably 

 not subject to gravity, since, as in the case of a solid moving 

 through a fluid, it probably is an effect of pressure reaction 

 and not a real increment of mass. 



All this is quite independent of the theory of relativity. 



The inertia factor for small speeds f is (l — v 2 /c 2 )~^, or 



* Communicated by the Author. 



t The simple factor for inertia-increase »i/#? =(l— i> 2 /e 2 )~ 5 is supposed 

 to be an approximation, though a close one, to a more complicated 

 expression, such as 



m = 3 /-, , 40_ _ 20- sin 20 \ 

 m 8 \ sin 20 sm20(l-cos2«)/ 



where sin 9 = v/c. 



See my book on ; Electrons,' pp. 133 & 225. This becomes 1 when 6 

 is small, slightly less than sec 6 when 6 is moderate, and approaches 



9/20 \ 



infinity in this form, y\\ ■ o^+l }, as 6 approaches frr. 



For instance, if v came within a tenth of 1 per cent, of the velocity 

 of light, so that sin = -999, the ratio m/m would be 20. 



Phil. Mag. S. 6. Vol. 34. No. 200. Aug, 1917. G 



