Portrait of Heinrich Rudolf Hertz (1857-1894), German physicist and discoverer of radio waves. Hertz studied at Berlin, gaining his PhD in 1880. He then moved to Kiel, where he started investigations in electromagnetism. He used Maxwell's theories to construct an oscillating electrical circuit with a spark gap. With such a circuit, Maxwell had predicted that electromagnetic radiation would be produced. Hertz showed this to be correct, and devised a loop antenna to detect the waves. He was also able to show that these waves travelled at the speed of light. Hertz died from blood poisoning at the age of 36 whilst a professor of physics at Bonn.