A volatile pile more or less as Volta made it. The shaded slads are silver, the blank ones are zinc and the salt soaked paste board is dark. The emf develops between silver and zinc in each pair of slabs up so that there is considerable voltage difference between the top and the bottom (Silver and Zinc).

Galvani  thought that this was a manifestation of animal electricity while Volta, a professor of natural philosophy at the nearby University of Pavia, successfully reproduced some of  Galvani's results with inanimate things. He assembles a series of silver and zinc disc in pairs, separating each pair with a sheet of pasteboard soaked in a conducting liquid ( Salt Water) .When the topmost disc of silver was connected by a wire with the lowest zinc disk, a steady current of electricity was produced. The basic reason for this electrochemical effects of electrical currents.