Original Tesla Induction Motor presented by Tesla to Prof. Ayrton

The induction motor is the most widely used form of electric motor because it is simple and robust. Nikola Tesla (1856-1943), who was born in Croatia but worked in America, made the first practical induction motors. He made this working model motor to illustrate the claims in his patents. Later, Tesla gave it to William Edward Ayrton (1847-1908), of the City and Guilds College (now part of Imperial College of Science Technology and Medicine). It is a two-phase machine (that is, it uses two alternating currents to produce the rotating magnetic field that makes the rotor turn).