Moistening bibulous paper with the iodide of potassium--a favourite test of his--and subjecting it to the action of machine electricity, he decomposed the iodide, and formed a brown spot where the iodine was liberated.

Then he immersed two wires, one of zinc, the other of platinum, each 1/13th of an inch in diameter, to a depth of 5/8ths of an inch in acidulated water during eight beats of his watch, or 3/20ths of a second; and found that the needle of his galvanometer swung through the same arc, and coloured his moistened paper to the same extent, as thirty turns of his large electrical machine.

Twenty-eight turns of the machine produced an effect distinctly less than that produced by his two wires.

Now, the quantity of water decomposed by the wires in this experiment totally eluded observation; it was immeasurably small; and still that amount of decomposition involved the development of a quantity of electric force which, if applied in a proper form, would kill a rat, and no man would like to bear it.
In his subsequent researches 'On the absolute Quantity of Electricity associated with the Particles or Atoms of matter,' he endeavours to give an idea of the amount of electrical force involved in the decomposition of a single grain of water.

He is almost afraid to mention it, for he estimates it at 800,000 discharges of his large Leyden battery.