The earliest of the inventions Included in The Spirit of Electricity is German scientist Otto von Guericke‘s electrostatic generator, dating from 1660. This machine could generate static electricity, like wool when you rub it, but in quantities impressive to the point of throwing large sparks.
To construct his device, von Guericke melted sulphur in a glass globe, which served as a destructible mould. The resultant sphere of sulphur was then mounted on an axle and set rotating within a wooden frame. As the sulphur ball rotated, he rubbed it with his hand or a cloth, charging it with static electricity and making sparks fly by bringing pieces of metal close to it.