( 569 ) 



Determination of the total charge of the electrons. 



4. Taking for granted the existence and also the nature of the 

 asymmetrical resolution as being in accordance with Voigt's theory, 

 it certainly is extremely interesting to interprete the result in the 

 language of electronic theory. 



LoRENTZ ^) has deduced Voigt's equations from the theory of elec- 

 trons or more accurately expressed he gives a system of ecjuations 

 which come to the same thing as those of Voigt, 



Let // be the intensity of the magnetic field, A the wavelength, 

 öX^ and (f)-^ the differences of wavelengths between the middle com- 

 ponejit and those towards violet and red, V the velocity of light in 



e 

 the aether, and — the well-known ratio of charge and mass of the 

 m 



electron, then according to Lorentz : 



4.jtV 



-^-rKi^^K'^K (1) 



F'or ffP-i = 61^ this formula changes into the equation, which first 



e 

 enabled us to determine — . This ratio is found in electromagnetic 



m 



units. 



If N denote the number of molecules per unit volume, one elec- 

 tron vibrating in each molecule, we have also according to Lorentz 



Ne— ' ' (2) 



These formulae were already communicated by Gehrcke and 

 VON Baeyer^). 



My own observations concerning asymmetry (§ 5 of my paper 

 cited ') and § 3 above) seem at first sight to be in contradiction 

 with this formula. One of my i-esults being that the asymmetry 

 varies with strength of field, according to (2) Ne must vary also, 

 because H and l^rf;.^ . (\).^ change in nearly the same ratio. Now an 

 increase of Ne, or of the number of radiating particles per unit 

 volume, must manifest itself in the radiating power of the vacuum 

 tube. An inspection of Plate II (paper cited sub ^)) shows that in 

 my experiments the intensity of the light of the components really 

 has been a maximum in the strongest part of the field. We must 

 therefore conclude that the circumstances of the luminous mercury 

 vapour in the Geissler tube were slightly different in the various 

 parts of the non-uniform magnetic field. 



^) Lorentz. Rapports pr(^sentés au congres inlernalional de physique 11)00. 



-) Gehbckk u. v. B,\eykh. Verliandl. deulsdi pliysik. Gesellsch. 7. p. 4()f. f906. 



*) Zeeman. These Proceedings 30 November 1907. 



39* 



