512 
xAIE. H. A. WILSON ON THE ELECTRICAL CONDUCTIVITY 
any height above the lower pair. The battery and galvanometer connected with the 
iipj)er pair were insulated so that the electrodes took up the potential of the flame. 
It was found that applying an E.M.F. to the lower electrodes affected the current 
between the upper pair very little, if at all, in the case of the conductivity due 
LT, Upper electrodes. 
to a salt vapour. With a normal solution of potassium carbonate the following 
currents were obtained ; the upper electrodes being about 3 centims. above the 
lower :— 
(1.) No E.M.F. on the lower pair— 
Current between the upper pair . . . . 66 divisions. 
(2.) 360 volts on the lower pair—■ 
Current between the upper pair .... 65 ,, 
With 700 volts on the lower pair the current between the upper pair was slightly 
increased or diminished, according to the direction of the current between the lower 
pair, showing that tLo upper pair took up some of the current from the lower 
electrodes. 
This effect became less as the distance between the two pairs was increased. 
