Macedonio Melloni (1798-1854), Italian physicist. Melloni was born at Parma. In 1824 he was appointed professor at Parma University, although he had to flee in 1831 after participating in the revolution. He went first to France, where he conducted experiments in radiant heat. He invented the thermomultiplier, a combination of thermopile and galvanometer used to quantify amounts of heat energy detected. He used a modifed optical bench to show that radiant heat has many of the same properties as light, notably reflection, refraction and polarisation. In 1848 he moved to Naples and was appointed director of the Vesuvius Observatory. He died of cholera at the age of 60.