The Galvani-Volta controversy

4. Volta's position
Volta read Galvani’s Commentarius in March 1792 and incredulously repeated all the experiments. In a few weeks he passed from incredulity to fanaticism. But on the basis of fresh experiments, he soon became convinced of the presence of artificial electricity, due to the action of metals as the “movers of electricity”. He realised that the bimetal arc simply acted on the frog’s nerves, and on his own tongue, producing a particular taste. In November he concluded that different kinds of metals had electro-motive power at the point where they are in contact with the frog. He summed up his ideas in the famous phrase: “It’s the difference in metals that does it.”
So, to explain the phenomenon, Volta was ready to change the principles of electrology which considered metals as mere conductors of electricity