John Randall (physicist)

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Sir John Turton Randall
Born 23 March 1905
Newton-le-Willows, Lancashire, England
Died 16 June 1984
Residence UK
Fields Experimental physicist and biophysicist
Institutions GEC, The Cavendish Laboratory of the University of Cambridge, King's College in the University of London and Dept. of Zoology at the University of Edinburgh
Alma mater University of Manchester and The Cavendish Laboratory of the University of Cambridge
Doctoral advisor Nobel-prize winner, Sir-William Lawrence Bragg, Head of The Cavendish Laboratory
Doctoral students 49[citation needed]
Known for High-power, multi-cavity magnetron for British and American radar stations in WWII, DNA structure determination, neutron diffraction studies of labelled proteins
Notable awards Hughes Medal (1946)
FRSE
John Price Wetherill Medal (1958)
Fellow of the Royal Society[1]

Sir John Turton Randall, DSc, FRS,[1] 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[edit]

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.[1] 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.[1] They had one son, Christopher, born in 1935.[1]

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.[1]

The Magnetron[edit]

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[2] 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[3]

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]

King's College London[edit]

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.[4] 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.[5] 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.[5]

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.[1]

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.[1] In 1958 he published a study of the structure of protozoa.[1] 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[edit]

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[edit]

Books featuring Sir John Randall, FRSE[edit]

  • 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[edit]

See also[edit]

External links[edit]