Henry Albert Howard Boot (29 July 1917 – 8 February 1983) was an English physicist who with Sir John Randall and James Sayers developed the

cavity magnetron The cavity magnetron is a high-power vacuum tube used in early radar systems and subsequently in microwave ovens and in linear particle accelerators. A cavity magnetron generates microwaves using the interaction of a stream of electrons wit ...

, which was one of the keys to the Allied victory in the

Second World War World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

Biography

Henry Boot was born in

Birmingham Birmingham ( ) is a City status in the United Kingdom, city and metropolitan borough in the metropolitan county of West Midlands (county), West Midlands, within the wider West Midlands (region), West Midlands region, in England. It is the Lis ...

and attended

King Edward's School, Birmingham King Edward's School (KES) is an independent school (UK), independent day school for boys in the British Public school (UK), public school tradition, located in Edgbaston, Birmingham. Founded by Edward VI of England, King Edward VI in 1552, it ...

and the

University of Birmingham The University of Birmingham (informally Birmingham University) is a Public university, public research university in Birmingham, England. It received its royal charter in 1900 as a successor to Queen's College, Birmingham (founded in 1825 as ...

. While working on his PhD the war broke out. His professor Mark Oliphant had seen the klystron at

Stanford University Leland Stanford Junior University, commonly referred to as Stanford University, is a Private university, private research university in Stanford, California, United States. It was founded in 1885 by railroad magnate Leland Stanford (the eighth ...

but it produced insufficient power to be useful as a

radar Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track ...

transmitter. He assigned John Randall and Boot to the problem. By late February 1940, they had invented the much more powerful

which was fitted in an experimental radar by May 1940. James Sayers later refined the magnetron still further by strapping alternate cavities. As with many British inventions of this period, the magnetron was provided to the US for free when they entered

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. Initially Boot and Randall were awarded £50 each for the magnetron for "improving the safety of life at sea", but in 1949 Boot, Randall and Sayers received a £36,000 prize for their work. After a brief time at

British Thomson-Houston British Thomson-Houston (BTH) was a British engineering and heavy industry, heavy industrial company, based at Rugby, Warwickshire, England. Originally founded to sell products from the Thomson-Houston Electric Company, it soon became a manufac ...

, Rugby, in the latter years of the war, Boot returned to Birmingham as the Nuffield Research Fellow. After some work on nuclear physics, Boot returned to magnetrons and after the war built a

cyclotron A cyclotron is a type of particle accelerator invented by Ernest Lawrence in 1929–1930 at the University of California, Berkeley, and patented in 1932. Lawrence, Ernest O. ''Method and apparatus for the acceleration of ions'', filed: Januar ...

at Birmingham. In 1948 he joined the Scientific Civil Service, and was appointed Principal Scientific Officer (PSO) at Services Electronic Research Laboratories, in Baldock in

Hertfordshire Hertfordshire ( or ; often abbreviated Herts) is a ceremonial county in the East of England and one of the home counties. It borders Bedfordshire to the north-west, Cambridgeshire to the north-east, Essex to the east, Greater London to the ...

, where he undertook research on microwaves, magnetrons, plasma physics and lasers. He enjoyed sailing, owning two boats at Salcombe in Devon. He frequently went down there to the family holiday home with his wife Penelope, and his two sons, Christopher and Nicholas. He retired in 1977 and died in Cambridge on 8 February 1983.

References

{{DEFAULTSORT:Boot, Harry 1917 births People educated at King Edward's School, Birmingham 1983 deaths English physicists Radar pioneers Alumni of the University of Birmingham Scientists from Birmingham, West Midlands Members of HM Scientific Civil Service Civil servants in the Admiralty 20th-century Royal Navy personnel 20th-century English scientists 20th-century British physicists 20th-century British civil servants