Irish-born Louis Brennan sealed a patent for his a twin-propeller torpedo in 1878. While predated by other models, the Brennan Torpedo is considered the first practical guided missile due to its range, speed and the simplicity of its concept.
The torpedo was powered by dual counter-rotating propellers operated by wires attached to winding engines on shore. The torpedo’s trajectory was guided by altering the speed of each extending wire.
With backing from several Melbourne businessmen Brennan founded the Brennan Torpedo Co. before selling the weapon to the British Government in 1887 for £110,000. It was purchased due to its effectiveness as a harbour defence and remained in production until 1906.