1893 Columbian Exposition Chicago

    The International Exposition was held in a building which was devoted to electrical exhibits. General Electric Company (backed by Thomas Edison and J.P. Morgan) had proposed to power the electric exhibits with direct current originally at the cost of US$1.8 million. After this was initially rejected as exorbitant, General Electric re-bid their costs at $554,000. However, Westinghouse proposed using its alternating current system to illuminate the Columbian Exposition in Chicago for $399,000, and Westinghouse won the bid.^[11] It was a key event in what has been called the War of the currents, an early demonstration in America of the safety and reliability of alternating current.^[19]
     All the exhibits were from commercial enterprises. Thomas Edison, Brush, Western Electric, and Westinghouse had exhibits. General Electric banned the use of Edison's lamps in Westinghouse's plan in retaliation for losing the bid. Westinghouse's company quickly designed a double-stopper lightbulb (sidestepping Edison's patents) and was able to light the fair. The Westinghouse lightbulb was invented by Reginald Fessenden, later to be the first person to transmit voice by radio. Fessenden replaced Edison's delicate platinum lead-in wires with an iron-nickel alloy, thus greatly reducing the cost and increasing the life of the lamp.^[20]
     The Westinghouse Company displayed several polyphase systems. The exhibits included a switchboard, polyphase generators, step-up transformers, transmission line, step-down transformers, commercial size induction motors and synchronous motors, and rotary direct current converters (including an operational railway motor). The working scaled system allowed the public a view of a system of polyphase power which could be transmitted over long distances, and be utilized, including the supply of direct current. Meters and other auxiliary devices were also present.

World's Fair Tesla alternating current and electromechanical presentation.

      Part of the space occupied by the Westinghouse Company was devoted to demonstrations of electrical devices developed by Nikola Tesla^[21] including a two-phase induction motor, and generators to power the system.^[22] Tesla demonstrated a series of electrical effects, some which were in previous lectures performed in America and Europe.^[23] This included using high-voltage, high-frequency alternating current to light a wireless gas-discharge lamp.^[24]