Place the anode and the cathode in a sealed container containing conductive water. Attach a rubber hose with a valve end to the output of the sealed container. Allow pressure to build a few PSI. Place the rubber output hose in a separate bucket full of soapy water. Open the valve to create lots of bubbles. Throw A Match Into the bucket of Bubbles and repeat. NOTE switches are used to draw a picture and are not necessary.
