William Henry Bragg

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Sir William Henry Bragg
William Henry Bragg Nobel bw.jpg
Born (1862-07-02)2 July 1862
Wigton, Cumberland, England
Died 12 March 1942(1942-03-12) (aged 79)
London, England
Residence England
Nationality British
Alma mater Trinity College, Cambridge
Known for X-ray diffraction
Bragg peak
Awards Nobel Prize in Physics (1915)
Barnard Medal (1915)
Matteucci Medal (1915)
Rumford Medal (1916)
Copley Medal (1930)
Faraday Medal (1936)
John J. Carty Award (1939)
Scientific career
Fields Physics
Institutions University of Adelaide
University of Leeds
University College London
Royal Institution
Academic advisors J. J. Thomson
Notable students W. L. Bragg
Kathleen Lonsdale
William Thomas Astbury
John Desmond Bernal
John Burton Cleland
He is the father of Lawrence Bragg. Father and son jointly won the Nobel Prize.

Sir William Henry Bragg OM KBE PRS[1] (2 July 1862 – 12 March 1942) was a British physicist, chemist, mathematician and active sportsman who uniquely[2] shared a Nobel Prize with his son Lawrence Bragg – the 1915 Nobel Prize in Physics: "for their services in the analysis of crystal structure by means of X-rays".[3] The mineral Braggite is named after him and his son. He was knighted in 1920.


The Old Grammar School, Market Harborough, which has a plaque inside noting Bragg's attendance

Early years[edit]

Bragg was born at Westward near Wigton, Cumberland, the son of Robert John Bragg, a merchant marine officer and farmer, and his wife Mary née Wood, a clergyman's daughter. When Bragg was seven years old, his mother died, and he was raised by his uncle, also named William Bragg, at Market Harborough, Leicestershire. He was educated at the Grammar School there, at King William's College on the Isle of Man and, having won an exhibition (scholarship), at Trinity College, Cambridge. He graduated in 1884 as third wrangler, and in 1885 was awarded a first class honours in the mathematical tripos.[4][5][6]

University of Adelaide[edit]

In 1885[7], at the age of 23, Bragg was appointed (Sir Thomas) Elder Professor of Mathematics and Experimental Physics in the University of Adelaide,[8] and started work there early in 1886.[9] Being a skilled mathematician, at that time he had limited knowledge of physics, most of which was in the form of applied mathematics he had learnt at Trinity. Also at that time, there were only about a hundred students doing full courses at Adelaide, of whom less than a handful belonged to the science school, whose deficient teaching facilities Bragg improved by apprenticing himself to a firm of instrument makers. Bragg was an able and popular lecturer; he encouraged the formation of the student union, and the attendance, free of charge, of science teachers at his lectures.[5][6]

He met Gwendoline née Todd, a skilled water-colour painter, whom he married in 1889.[5][6] Their first son, William Lawrence, was born in North Adelaide in 1890 and he taught him at the University of Adelaide. He also played tennis and golf, and as a founding member of the North Adelaide and Adelaide University Lacrosse Clubs, contributed to the introduction of lacrosse to South Australia and was also the secretary of the Adelaide University Chess Association.[10]

Bragg's interest in physics developed, particularly in the field of electromagnetism. In 1895 he was visited by Ernest Rutherford, en route from New Zealand to Cambridge; this was the commencement of a lifelong friendship. Bragg had a keen interest in the new discovery of Wilhelm Röntgen. On 29 May 1896 at Adelaide, Bragg demonstrated before a meeting of local doctors the application of “X-rays to reveal structures that were otherwise invisible”. Samuel Barbour, senior chemist of F. H. Faulding & Co., an Adelaide pharmaceutical manufacturer, supplied the necessary apparatus in the form of a Crookes tube, a glass discharge tube. The tube had been obtained at Leeds, England, where Barbour visited the firm of Reynolds and Branson, a manufacturer of photographic and laboratory equipment. Barbour returned to Adelaide in April 1896. Barbour had conducted his own experiments shortly after return to Australia, but results were limited due to limited battery power.[11] At the University, the tube was attached to an induction coil and a battery borrowed from Sir Charles Todd, Bragg’s father-in-law. The induction coil was utilized to produce the electric spark necessary for Bragg and Barbour to “generate short bursts of X-rays”. The audience was favorably impressed. Bragg availed himself as a test subject, in the manner of Röntgen and allowed an X-ray photograph to be taken of his hand. The image of the fingers in his hand revealed “an old injury to one of his fingers sustained when using the turnip chopping machine on his father’s farm in Cumbria”.[12][13]

As early as 1895 Professor William H. (later Sir William) Bragg was working on wireless telegraphy, though public lectures and demonstrations focussed on his X-ray research which would later lead to his Nobel Prize. In a hurried visit by Rutherford, he was reported as working on a Hertzian oscillator. There were many common practical threads to the two technologies and he was ably assisted in the laboratory by Arthur Lionel Rogers who manufactured much of the equipment. On 21 September 1897 Bragg gave the first recorded public demonstration of the working of wireless telegraphy in Australia during a lecture meeting at the University of Adelaide as part of the Public Teachers' Union conference.[14][15] Bragg departed Adelaide in December 1897,[16] and spent all of 1898 on a 12 month leave of absence, touring Great Britain and Europe and during this time visited Marconi and inspected his wireless facilities.[17][18] He returned to Adelaide in early March of 1899,[19] and already on 13 May 1899 Bragg and his father-in-law Sir Charles Todd were conducting preliminary tests of wireless telegraphy with a transmitter at the Observatory and a receiver on the South Road (about 200 metres).[20] Experiments continued throughout the southern winter of 1899 and the range was progressively extended to Henley Beach. In September the work was extended to two way transmissions with the addition of a second induction coil loaned by Mr. Oddie of Ballarat.[21] It was desired to extend the experiments cross a sea path and Todd was interested in connecting Cape Spencer and Althorpe Island, but local costs were considered prohibitive while the charges for patented equipment from the Marconi Company were exorbitant. At the same time Bragg's interests were leaning towards X-rays and practical work in wireless in South Australia was largely dormant for the next decade.

The turning-point in Bragg's career came in 1904 when he gave the presidential address to section A of the Australasian Association for the Advancement of Science at Dunedin, New Zealand,[6] on "Some Recent Advances in the Theory of the Ionization of Gases". This idea was followed up "in a brilliant series of researches"[6] which, within three years, earned him a fellowship of the Royal Society of London. This paper was also the origin of his first book Studies in Radioactivity (1912). Soon after the delivery of his 1904 address, some radium bromide was made available to Bragg for experimentation. In December 1904 his paper "On the Absorption of α Rays and on the Classification of the α Rays from Radium" appeared in the Philosophical Magazine, and in the same issue a paper "On the Ionization Curves of Radium", written in collaboration with his student Richard Kleeman, also appeared.[5][6]

At the end of 1908 Bragg returned to England. During his 23 years in Australia "he had seen the number of students at the University of Adelaide almost quadruple, and had a full share in the development of its excellent science school."[5]

University of Leeds[edit]

Commemorative plaque on the Parkinson Building, University of Leeds
X-ray spectrometer developed by Bragg

Bragg occupied the Cavendish chair of physics in the University of Leeds from 1909. He continued his work on X-rays with much success. He invented the X-ray spectrometer and with his son, Lawrence Bragg, then a research student at Cambridge, founded the new science of X-ray crystallography, the analysis of crystal structure using X-ray diffraction.

From 1914, both father and son contributed to the war effort; W.H. Bragg was connected with submarine detection, at Aberdour on Forth and at Harwich, and returned to London in 1918 as a consultant to the Admiralty.[5]

In 1915 father and son were jointly awarded[2] the Nobel Prize in Physics for their studies, using the X-ray spectrometer, of X-ray spectra, X-ray diffraction, and of crystal structure. Ten years later, their volume X-Rays and Crystal Structure (1915) had reached a fifth edition.[5]

University College London[edit]

Bragg was appointed Quain Professor of physics at University College London in 1915, but did not take up his duties there until after World War I. While Quain professor at London he continued his work on crystal analysis.[5]

Royal Institution[edit]

From 1923 he was Fullerian Professor of Chemistry at the Royal Institution and director of the Davy Faraday Research Laboratory.[22] This institution was practically rebuilt in 1929–30 and, under Bragg's directorship many valuable papers were issued from the laboratory.[5] In 1919, 1923 and 1925 he was invited to deliver the Royal Institution Christmas Lecture on The World of Sound; Concerning the Nature of Things and Old Trades and New Knowledge respectively.


Bragg was elected Fellow of the Royal Society in 1907, vice-president in 1920, and served as President of the Royal Society from 1935 to 1940. Elected member of the Royal Academy of Science, Letters and Fine Arts of Belgium on 1.6.1946.

The lecture theatre of King William's College (KWC) is named in memory of Bragg; the Sixth-Form invitational literary debating society at KWC, the Bragg Society, is also named in his memory. One of the school "Houses" at Robert Smyth School, Market Harborough, Leicester, is named "Bragg" in memory of him being a student there. Since 1992, the Australian Institute of Physics has awarded The Bragg Gold Medal for Excellence in Physics for the best PhD thesis by a student at an Australian university. The two sides of the medal contain the images of Sir William Henry and his son Sir Lawrence Bragg.[23]

In 1889 in Adelaide, W.H. Bragg married Gwendoline Todd, a skilled water-colour painter, and daughter of astronomer, meteorologist and electrical engineer Sir Charles Todd. They had three children, a daughter, Gwendolen and two sons, (William) Lawrence (W.L.) and Robert. Robert was killed in the Battle of Gallipoli. W.H.'s wife Gwendoline died in 1929. W.H. Bragg died in 1942 in England and was survived by his daughter Gwendolen (Mrs. Alban Caroe) and his son, Sir Lawrence Bragg.

William H. Bragg was appointed Commander of the Order of the British Empire (CBE) in 1917 and Knight Commander (KBE) in 1920. He was admitted to the Order of Merit in 1931.[5]

The Experimental Technique Centre at Brunel University is named the Bragg Building.

In 1962, the Bragg Laboratories were constructed at the University of Adelaide to commemorate 100 years since the birth of Sir William H. Bragg.[5]

  • 1862 Born in Cumberland
  • 1869 Moved to Leicestershire
  • 1875 School on the Isle of Man
  • 1881–1885 Trinity College, Cambridge – Student
  • 1886–1908 University of Adelaide – Elder Professor of Mathematics and Experimental Physics
  • 1889 Married Gwendoline Todd in Adelaide
  • 1890 William Lawrence Bragg born in Adelaide
  • 1904 President of section A of the Australasian Association for the Advancement of Science
  • 1908 President of the Australasian Association for the Advancement of Science
  • 1909–15 University of Leeds – Cavendish professor of physics
  • 1915 Won the Nobel Prize In Physics with his son
  • 1915–23 University College LondonQuain Professor of physics
  • Royal Institution
    • Fullerian professor of chemistry
    • Director of the Davy Faraday Research Laboratory
    • In 1919, 1923, 1925 he was invited to deliver the Royal Institution Christmas Lecture on The World of Sound; Concerning the Nature of Things and Old Trades and New Knowledge respectively.
  • 1933 invented the Bragg-Paul Pulsator
  • 1942 Died in London



  • William Henry Bragg, The World of Sound (1920)
  • William Henry Bragg, The Crystalline State – The Romanes Lecture for 1925. Oxford, 1925.
  • William Henry Bragg, Concerning the Nature of Things (1925)
  • William Henry Bragg, Old Trades and New Knowledge (1926)
  • William Henry Bragg, An Introduction to Crystal Analysis (1928)
  • William Henry Bragg, The Universe of Light (1933)

See also[edit]


  1. ^ Da c. Andrade, E. N.; Lonsdale, K. (1943). "William Henry Bragg. 1862-1942". Obituary Notices of Fellows of the Royal Society. 4 (12): 276. doi:10.1098/rsbm.1943.0003. JSTOR 769040. 
  2. ^ a b This is still a unique accomplishment, because no other parent-child combination has yet shared a Nobel Prize (in any field). In several cases, a parent has won a Nobel Prize, and then years later, the child has won the Nobel Prize for separate research. An example of this is with Marie Curie and her daughter Irène Joliot-Curie, who are the only mother-daughter pair. Several father-son pairs have won two separate Nobel Prizes.
  3. ^ "The Nobel Prize in Physics 1915". Nobel Foundation. Retrieved 2008-10-09. 
  4. ^ "Bragg, William Henry (BRG880WH)". A Cambridge Alumni Database. University of Cambridge. 
  5. ^ a b c d e f g h i j k Serle, Percival (1949). "Bragg, William Henry". Dictionary of Australian Biography. Sydney: Angus and Robertson. Retrieved 7 October 2008. 
  6. ^ a b c d e f Tomlin, S. G. (1979). "Bragg, Sir William Henry (1862–1942)". Australian Dictionary of Biography. Canberra: Australian National University. Retrieved 7 October 2008. 
  7. ^ "The New Elder Professor of Mathematics". The Express And Telegraph. XXIII, (6,596). South Australia. 18 December 1885. p. 2 (Afternoon Edition.). Retrieved 11 February 2018 – via National Library of Australia. 
  8. ^ Bragg Centenary, 1886–1986, University of Adelaide, Pages 3 & 4. Proof of advertisement in the Oxford University Gazette of 16 October 1885, and the Cambridge University Reporter of 13 October 1885. The advertisements read:
    The Council invite applications for the above Professorship. Salary £800 per annum. The appointment will be for a term of five years, subject to renewal at the discretion of the Council. Salary will date from March 1, 1886, and the Professor will be expected to enter on his duties on that date. An allowance will be made for travelling expenses. Applications with testimonials should reach ... not later than December 1, 1885.
    Bragg was informed of his appointment by a letter dated 17 December 1885.
  9. ^ "THE ADELAIDE UNIVERSITY". The South Australian Advertiser. XXVIII, (8500). South Australia. 15 January 1886. p. 5. Retrieved 11 February 2018 – via National Library of Australia. 
  10. ^ Bragg Centenary, 1886–1986, University of Adelaide, page 43.
  11. ^ "RONTGEN PHOTOGRAPHY UNSUSPECTED". Evening Journal. XXVIII, (7976). South Australia. 30 May 1896. p. 7. Retrieved 11 February 2018 – via National Library of Australia. 
  12. ^ George, Robert. (1996). 100 Years of X-Rays – the South Australian Connection. The Journal of the Radiology History & Heritage Charitable Trust. 12(Autumn/Winter): 3.
  13. ^ Hall, Kersten T. (2014). The Man in the Monkeynut Coat: William Astbury and the Forgotten Road to the Double-Helix. Oxford University Press. Oxford. Page 26.
  14. ^ "PUBLIC TEACHERS' UNION". South Australian Register. LXII, (15,869). South Australia. 22 September 1897. p. 6. Retrieved 8 February 2018 – via National Library of Australia. 
  15. ^ "SECOND DAY". Adelaide Observer. LIV, (2,921). South Australia. 25 September 1897. p. 14. Retrieved 8 February 2018 – via National Library of Australia. 
  16. ^ "THE LATE MR. MCPHERSON". The Express And Telegraph. XXXV, (10,241). South Australia. 15 December 1897. p. 2 (ONE O'CLOCK EDITION). Retrieved 11 February 2018 – via National Library of Australia. 
  17. ^ "THE LATE MR. MCPHERSON". The Express And Telegraph. XXXV, (10,241). South Australia. 15 December 1897. p. 2 (ONE O'CLOCK EDITION). Retrieved 8 February 2018 – via National Library of Australia. 
  18. ^ "ASTRONOMICAL SOCIETY". The Advertiser. South Australia. 11 May 1899. p. 3. Retrieved 8 February 2018 – via National Library of Australia. 
  19. ^ "RETURN OF PROFESSOR BRAGG". Evening Journal. XXXI, (8817). South Australia. 6 March 1899. p. 2 (ONE O'CLOCK EDITION). Retrieved 11 February 2018 – via National Library of Australia. 
  20. ^ "WIRELESS TELEGRAPHY". South Australian Register. LXIV, (16,381). South Australia. 15 May 1899. p. 4. Retrieved 8 February 2018 – via National Library of Australia. 
  21. ^ "WIRELESS TELEGRAPHY". Evening Journal. XXXI, (8989). South Australia. 28 September 1899. p. 2 (ONE O'CLOCK EDITION). Retrieved 11 February 2018 – via National Library of Australia. 
  22. ^ William Henry Bragg (1862–1942). The Davy Faraday Research Laboratory
  23. ^ "Bragg Gold Medal for Excellence in Physics". Australian Institute of Physics. 2009. Retrieved 11 January 2009. 
  24. ^ "John J. Carty Award for the Advancement of Science". National Academy of Sciences. Archived from the original on 29 December 2010. Retrieved 25 February 2011. 

Further reading[edit]

  • "[a] most valuable record of his work and picture of his personality is the excellent obituary written by Professor Andrade of London University for the Royal Society of London." Statement made by Sir Kerr Grant, in:
  • "The Life and work of Sir William Bragg", the John Murtagh Macrossan Memorial Lecture for 1950, University of Queensland. Written and presented by Sir Kerr Grant, Emeritus Professor of Physics, University of Adelaide. Reproduced as pages 5–37 of Bragg Centenary, 1886–1986, University of Adelaide.
  • "William and Lawrence Bragg, Father and Son: The Most Extraordinary Collaboration in Science", John Jenkin, Oxford University Press 2008.
  • Ross, John F. A History of Radio in South Australia 1897-1977 (J. F. Ross, 1978) [1]

External links[edit]