First lightning detector

The oldest form of lightning detector is the lightning bell, created in 1742 by British inventor Andrew Gordon at the University of Erfurt, Germany. It produced sound by converting electrical energy into movement when a bell clapper was between two oppositely charged bells; the device was often referred to as "electric chimes". Developing this further, a decade later US inventor Benjamin Franklin famously connected one bell to a metal rod on his roof and another to the ground. A passing charged cloud would cause the bell to ring indicating that lightning was probable.