John Randall (physicist)

Sir John Turton Randall, DSc, FRS,^[2] FRSE (23 March 1905 – 16 June 1984) was a British physicist and biophysicist, credited with radical improvement of the cavity magnetron, an essential component of centimetric wavelength radar, which was one of the keys to the Allied victory in the Second World War. It is also the key component of microwave ovens. He also led the King's College London team which worked on the structure of DNA; his deputy, Professor Maurice Wilkins, shared the 1962 Nobel Prize for Physiology or Medicine, together with James Watson and Francis Crick of the Cavendish Laboratory at the University of Cambridge, for the determination of the structure of DNA. His other staff included Rosalind Franklin, Raymond Gosling, Alex Stokes and Herbert Wilson, all involved in research on DNA.

Origins

John Randall was born on 23 March 1905 at Newton-le-Willows, Lancashire, the only son and the first of the three children of Sidney Randall, nurseryman and seedsman, and his wife, Hannah Cawley, daughter of John Turton, colliery manager in the area.^[2] He was educated at the grammar school at Ashton-in-Makerfield and at the University of Manchester, where he was awarded a first-class honors degree in physics and a graduate prize in 1925, and an MSc in 1926.^{[citation needed]} He married Doris, daughter of Josiah John Duckworth, a colliery surveyor, in 1928.^[2] They had one son, Christopher, born in 1935.^[2]

From 1926 to 1937 Randall was employed on research by the General Electric Company at its Wembley laboratories, where he took a leading part in developing luminescent powders for use in discharge lamps.^{[citation needed]} He also took an active interest in the mechanisms of such luminescence.^[2]

The Magnetron

By 1937 he was recognized as the leading British worker in his field, and was awarded a Royal Society fellowship to the University of Birmingham, where he worked on the electron trap theory of phosphorescence in Professor Marcus Oliphant's physics faculty.^{[citation needed]} When the war began in 1939 Randall transferred to the large group working on centimeter radar. At the time limited transmitter output was the greatest single obstacle in the development of this type of radar.^{[citation needed]}

Simple two-pole magnetrons had been developed in the 1920s but gave relatively low power outputs. A more powerful multi-cavity resonant magnetron had been developed in 1935^[3] by Hans Erich Hollmann in Berlin. By 1940 Randall and Dr Harry Boot produced a working prototype similar to Hollman's cavity magnetron, but added liquid cooling and a stronger cavity. However Randall and Boot soon managed to increase its power output 100-fold. As Prof. W. E. Burcham recollects:

John Randall and Harry Boot, two young physicists were assigned to the task. Within two months (21 February 1940) they had produced a new kind of magnetron, one with eight concentric cavities… Randall got the inspirational idea of using eight cavities when he researched the design of the original Hertz oscillator which was an open single ring. Randall saw that this structure could be extrapolated into a cylinder and then into eight resonating chambers^[4]

In 1943 Randall left Oliphant's physical laboratory in Birmingham to teach for a year in the Cavendish Laboratory at Cambridge.^{[citation needed]} In 1944 Randall was appointed professor of natural philosophy at University of St Andrews and began planning research in biophysics (with Maurice Wilkins) on a small Admiralty grant.^{[citation needed]}

Double Helix William Astbury Oswald Avery Lawrence Bragg Francis Crick Erwin Chargaff Jerry Donohue Rosalind Franklin Raymond Gosling Frederick Griffith Phoebus Levene Friedrich Miescher Fred Neufeld Sir John Randall Alex Stokes James Watson Maurice Wilkins Herbert Wilson

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King's College London

In 1946, John T Randall - who had as Ph.D. advisor the Nobel-Prize winning physicist, William Lawrence Bragg - was appointed Head of Physics Department at King’s College in London.^{[citation needed]} He then moved to the Wheatstone chair of physics at King's College London, where the Medical Research Council set up the Biophysics Research Unit with Randall as the director (now known as Randall Division of Cell and Molecular Biophysics) at King's College London.^{[citation needed]} During his term as Director the experimental work leading to the discovery of the structure of DNA was made there by Rosalind Franklin, Raymond Gosling, Maurice Wilkins, Alex Stokes and Herbert R. Wilson. He assigned Raymond Gosling as a PhD student to Dr. R. Franklin to work on DNA structure by X-ray diffraction.^[5] According to Raymond Gosling, the role of John Randall in the pursuit of the double helix cannot be overstated. Gosling felt so strongly on this subject that he wrote to The Times in 2013 during the sixtieth anniversary celebrations.^[6] Randall firmly believed that DNA held the genetic code and assembled a multi-disciplinary team to help prove it. It was Randall who pointed out that since DNA was largely carbon, nitrogen and oxygen, it was just the same as the atoms in the air in the camera. The result was a diffuse back-scattering of X-rays, which fogged the film, and so he instructed Gosling to displace all the air with hydrogen.^[6]

Maurice Wilkins shared the 1962 Nobel Prize for Physiology and Medicine with James Watson and Francis Crick; Rosalind Franklin had already died from cancer in 1958.

In addition to the X-Ray diffraction work the unit conducted a wide-ranging programme of research by physicists, biochemists, and biologists. The use of new types of light microscopes led to the important proposal in 1954 of the sliding filament mechanism for muscle contraction.^{[citation needed]} Randall was also successful in integrating the teaching of biosciences at King's College.^[2]

In 1951 he set up a large multidisciplinary group working under his personal direction to study the structure and growth of the connective tissue protein collagen.^{[citation needed]} Their contribution helped to elucidate the three-chain structure of the collagen molecule.^{[citation needed]} Randall himself specialized in using the electron microscope, first studying the fine structure of spermatozoa and then concentrating on collagen.^[2] In 1958 he published a study of the structure of protozoa.^[2] He set up a new group to use the cilia of protozoa as a model system for the analysis of morphogenesis by correlating the structural and biochemical differences in mutants.

Later years

In 1970 he retired to Edinburgh University, where he formed a group which applied a range of new biophysical methods, such as coherent neutron diffraction studies of protein crystals in ionic solutions in heavy water, to study by neutron diffraction and scattering various biomolecular problems, such as the proton exchange of protein residues by deuterons.^{[citation needed]}

Honors

• In 1938 Randall was awarded a DSc by the University of Manchester.^{[citation needed]}
• In 1943 he was awarded (with H. A. H. Boot) the Thomas Gray memorial prize of the Royal Society of Arts for the invention of the cavity magnetron.
• In 1945 he became Duddell medallist of the Physical Society of London and shared a payment from the Royal Commission on Awards to Inventors for the magnetron invention.
• In 1946 he was elected a fellow of the Royal Society^[2] and became its Hughes medalist.
• Further awards (with Boot) for the magnetron work were, in 1958, the John Price Wetherill medal of the Franklin Institute of the state of Pennsylvania and, in 1959, the John Scott award of the city of Pennsylvania.^[2]
• In 1962 he was knighted, and in 1972 he became a fellow of the Royal Society of Edinburgh.

v t e DNA structure research at King's College London 1947–1959 Rosalind Franklin Raymond Gosling John Randall Alexander Stokes Maurice Wilkins Herbert Wilson

Books featuring Sir John Randall, FRSE

• Chomet, S. (Ed.), D.N.A. Genesis of a Discovery, 1994, Newman- Hemisphere Press, London.
• Wilkins, Maurice, The Third Man of the Double Helix: The Autobiography of Maurice Wilkins. ISBN 0-19-860665-6.
• Ridley, Matt; "Francis Crick: Discoverer of the Genetic Code (Eminent Lives)" first published in July 2006 in the US and then in the UK. September 2006, by HarperCollins Publishers ISBN 0-06-082333-X.
• Tait, Sylvia & James "A Quartet of Unlikely Discoveries" (Athena Press 2004) ISBN 1-84401-343-X
• Watson, James D., The Double Helix: A Personal Account of the Discovery of the Structure of DNA, Atheneum, 1980, ISBN 0-689-70602-2 (first published in 1968).

Notes

See also

• Magnetron
• A magnetron precursor prototype in 1935

External links

• Biography and picture of John Randall at the King's College website
• Randall Division of Cell and Molecular Biophysics website
• Key Participants: J. T. Randall - Linus Pauling and the Race for DNA: A Documentary History