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IOWA ACADEMY - OF SCIENCE Voi.. XXVII, 1920 
condenser and the grid were connected in series. The negative 
pole was connected to the inductance the primary coil and the 
filament in series. 
To measure any electrolysis due to any unindirectional compo- 
nent that the current might have, the secondary circuit was closed 
with a silver coulometer (M) in series with telephones (T). The 
current was passed through a 0.1 normal silver nitrate solution 
for a total of fifteen hours and there was no change of weight 
of the electrodes. 
Fig. 37 
