(6) 



methods for investigating the electric effect. A description of the 

 experiments follows in the second part of this paper; in the present 

 communication 1 shall explain their theoretical foundations. A criterion 

 for a dissymmetry, governed by electric actions, can be established, 

 by means of which it shall be possible to fix a limit for the magnitude 

 of the electric effect. 



5. The first problem that I will consider relates to the vibrations 

 of an electron under the simultaneous influence of parallel electric 

 and magnetic fields. 



Let a system of three rectangular axes be chosen and let the 

 magnetic force be parallel to the axis OZ. 



Let I, t], 'C, be the components of the displacement of an electron, 

 then the equations of motion are 



1= — b- lA-ri] h = — ^'' >/ — *• 5 ... (6) 

 Z — —(r: (7) 



The difference of a and h determines the electric effect, the 

 magnetic one is determined by v. Suppose b > a and put h — a^ .v, 

 hence s positive. 



(7) gives the frequency a ; the vibrations corresponding to this 

 equation are always parallel to the axis (JZ. 



In (6) we assume 



<l being in general a complex quantity. Tiie real motion of the electron 

 is obtained by taking the real parts of the expressions for § and i;. 

 Making the substitution, we get: 



— rr r=: — h^ -\- i « ^ '/ ? — n"^ q z=z — h" q — 'i rn . (8) 



(n- — b-f = -]-)>■ ?■' 



hence 



n = b±^ = a+s±^ (9) 



From (8) we obtain two values for q, viz: 



q= ±i (10) 



6. We shall now consider 3 special cases. 



Case I. Electric field = 0, hence s = 0. Upper signs iu (9) and 

 (10). We then have for the motion in the plane of A^]'. 



n = rt -j- - r , q = -\r i- 



The lower signs in (9) and (10) give 



