Robert John Strutt, 4th Baron Rayleigh

Who was Robert John Strutt, 4th Baron Rayleigh?

Robert John Strutt, 4th Baron Rayleigh FRS was a British peer and physicist. He discovered "active nitrogen", was the first to distinguish the glow of the night sky.

He was born at Terling Place, the family home near Witham, Essex, the eldest son of John William Strutt, 3rd Baron Rayleigh and his wife Evelyn Georgiana Mary. He was thus a nephew of Arthur Balfour and of Eleanor Mildred Sidgwick. He was educated at Eton College and Trinity College, Cambridge, where he initially read mathematics, but changed after two terms to Natural Sciences. He became a research student in physics at the Cavendish Laboratory under J. J. Thomson, whose biography he subsequently wrote. His work at this time was on discharge of electricity through gases, including early work on x-rays and electrons. He wrote one of the first books on radioactivity, The Becquerel rays and the properties of radium. He was awarded the Coutts Trotter studentship in 1898 and was a Fellow of Trinity College 1900–1906.

Strutt was elected a Fellow of the Royal Society in May, 1905 when his candidature citation read: "Fellow of Trinity College, Cambridge.