Each cell consists of 75 x 25 mm glass cylinder with 2 hole rubber stopper fitted with carbon electrodes. Electrical contact is made through the crocodile clips and a piece of insulating material between the electrodes prevents short circuiting. The gases evolved are collected in two 75 x 10 mm test tubes suspended over the electrodes by piece of wood and rubber bands (not supplied).
This kit uses the juice within lemon as an electrolyte in an oxidation-reduction reaction to produce useful electricity sufficient to power clock. The electrodes must be sanded clean between each attempt. Requires lemons to make ""batteries"" in series to generate sufficient voltage to power the clock.