Heinrich Hertz , German physicist, with his wife Elizabetth, 1886.
© Science Museum / Science & Society Picture Library
Photograph with Heinrich Hertz with his wife, Elizabeth, at the time of their marriage. Hertz (1857-1894) discovered 'Hertzian waves' (electromagnetic waves) and discovered that they behaved like light waves except for their wavelength. He was reputedly the first person to transmit and receive radio waves and the unit of frequency of radio waves is named after him.