Whitehead — Magnetic Effect of Electric Disjplacement. 115 



filament, which is beantifiilly adapted to this purpose. The 

 distance of the scale from the mirror was 110^°". The connec- 

 tions are shown in fig. 3. The generator, G, was a Westing- 

 house " smooth-bodv," giving a pm-e sine wave, 1000 volts, 

 133 cycles ; the transformers, T, T, T, were all Westinghoiise 

 make. The transformer T^, giving the high voltage, was built 

 privately ; it was of closed magnetic tyi^e and had a ratio of 1 

 to 80. By a suitable arrangement of switches 110, 200, or 100 

 volts could be put on the coils. The two magnetizing coils 

 were connected in multiple and so that they worked together ; 

 i. e., at any instant the fields were equal, parallel, and in the 

 same direction. The electrodes were also in multiple, but 

 worked in opposite directions, i. e., at any instant the fields 



were equal, parallel, but in opposite directions. In each circuit 

 there was a reversing switch, R S. 



Calculation of Effect Expected. — Following is a calculation 

 of the magnitude of the effect in the apparatus as constructed 

 and experimented upon. 



Each pair of electrodes were l-Q*^"" apart; the dielectrics were 

 blocks of rock salt, glass or paraffin, V^ X I''"' X '63'^°' and they 

 were hung with their square faces parallel to the electrodes, so 

 that one-third the length of a line of force was within the 

 dielectric ; thus v/2-8800 being the maximum E.M.F. between 

 the electrodes the proportion of it active on the dielectric is 

 given by : 



^2.8800 



Y = 



the intensity of E.M.F. F„, = 



a/2 . 8800 



2K4-I 

 dl 



F,7, = 



(2K + l)x-63 



(maximum value in volts). 



