In 1894, the first example of wirelessly controlling at a distance was during a demonstration by the British physicist Oliver Lodge, in which he made use of a Branly's coherer to make a mirror galvanometer move a beam of light when an electromagnetic wave was artificially generated. In 1895, Jagadish Chandra Bose demonstrated radio waves by triggering a gun and sounding a bell using microwaves transmitted over a distance of 75 feet through intervening walls. Radio innovators Guglielmo Marconi and William Preece, at a demonstration on December 12, 1896, at Toynbee Hall made a bell ring by pushing a button in a box that was not connected by any wires. In 1897 a British engineer and professor in the Electrical Engineering Department at King's College London, Ernest Wilson, had invented a remote radio control of torpedoes and submarines that was controlled by "Hertzian" wave.