Microwaves were first predicted by James Clerk Maxwell
(second picture) in 1864 by use of his equations. Later during 1888 Heinrich Hertz
(third picture) proved the existence of microwaves by building a device that produced and detected microwave radiation. His device used a horse trough, a wrought iron point spark, Leyden jars, and a length of zinc gutter with a parabolic cross-section that worked as a reflection antenna. In 1894 J. C. Bose
(fourth picture) publicly demonstrated radio control of a bell using millimeter wavelengths, and conducted research into the broadcasting of microwaves.