Here are the discs that form the voltaic pile, the most simple electric battery. One of the iron discs is not pictured, as is it set into the clay cup that will hold the pile. The copper could be pounded flat while cold with a stone, while the iron needed to be orange hot to pound. I dropped the bits into the furnace-operating in it’s third role as a forge- and then set them on an anvil stone and pounded them with a rock like a blacksmith. Alternating iron, potato, copper, gives a voltage that increases with each stack. Finishing these iron bits gives me the last material I need to create a working, powered telegraph key…