Experiment in wireless power transmission by Nikola Tesla at his laboratory in Colorado Springs in 1899
An experiment in wireless power transmission by Nikola Tesla at his laboratory in Colorado Springs in 1899. This is a bank of lights attached to a large 50 foot wire loop antenna, receiving power from Tesla's high voltage "oscillator" transmitter, a large Tesla coil 100 feet away. This experiment seems to be Tesla's longest distance power transmission for which there is hard evidence.
Caption of the picture in Tesla's June 1900 Century magazine article: "EXPERIMENT TO ILLUSTRATE AN INDUCTIVE EFFECT OF AN ELECTRICAL OSCILLATOR OF GREAT POWER - The photograph shows three ordinary incandescent lamps lighted to full candle-power by currents induced in a local loop consisting of a single wire forming a square of fifty feet each side, which includes the lamps, and which is at a distance of one hundred feet from the primary circuit energized by the oscillator. The loop likewise includes an electrical condenser, and is exactly attuned to the vibrations of the oscillator, which is worked at less than five percent of its total capacity."