Wheatstone bridge

The Wheatstone Bridge (named after its popularizer, not original inventor) is an electrical circuit used to measure unknown electrical resistances with high accuracy. It became a critical instrument in scientific research and electrical engineering.
 Charles Wheatstone England 1843 Wheatstone bridge

The Wheatstone Bridge (named after its popularizer, not original inventor) is an electrical circuit used to measure unknown electrical resistances with high accuracy. It became a critical instrument in scientific research and electrical engineering.