John Ambrose Fleming

Sir John Ambrose Fleming
Fleming in 1890
Born	(1849-11-29)29 November 1849 Lancaster, Lancashire, England
Died	18 April 1945(1945-04-18) (aged 95) Sidmouth, Devon, England
Education	Lancaster Royal Grammar School University College School
Alma mater	University College London (BSc, 1870) University of London (DSc, 1879) St John's College, Cambridge (BA, 1881)
Known for	Fleming valve (1904)
Spouses	Clara Ripley Pratt ​ ​ (m. 1887; died 1917)​ Olive May Franks ​ (m. 1928)​
Awards	IRE Medal of Honor (1933)
Honours	Knight Bachelor (1929)
Engineering career
Discipline	Electrical engineering
Institutions	University College London (1884–1927)
Employer(s)	Edison and Swan Electric Light Company Marconi's Wireless Telegraph Company
1st Pender Professor of Electrical Engineering
In office 1899–1925
Preceded by	Office established
Succeeded by	Wellesley Curram Clinton

Sir John Ambrose Fleming (29 November 1849 – 18 April 1945) was an English electrical engineer who invented the vacuum tube,^[1] designed the radio transmitter with which the first transatlantic radio transmission was made, and also established the right-hand rule used in physics.^[2]

He was born in Lancaster, Lancashire and was baptised on 11 February 1850, the eldest of seven children of James Fleming DD (died 1879), a Congregational minister, and his wife Mary Ann.^[3] A devout Christian, he once preached at St Martin-in-the-Fields in London on evidence for the resurrection.

In 1932, he and Douglas Dewar and Bernard Acworth helped establish the Evolution Protest Movement. Fleming bequeathed much of his estate to Christian charities, especially those for the poor. He was a noted photographer, painted watercolours, and enjoyed climbing the Alps.