I — Tesla's contribution to electric power

FARADAY'S principle of electromagnetic induction discovered in 1831 after some 40 years of incubation resulted in practical forms of dynamo machines. Electricity from mechanical power (instead of costly batteries) stimulated invention of apparatus and the development of various methods or “systems” for distributing and utilizing the electric current. The evolution of “systems” culminated in Tesla's polyphase alternating current, with its unique induction motor. His system has dominated the development of electric service during a half century and continues today as our method of using electric power.