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William Henry Bragg

 
Britannica Concise Encyclopedia: Sir William Henry Bragg
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(b. July 2, 1862, Wigton, Cumberland, Eng. — d. March 12, 1942, London) British scientist, a pioneer in solid-state physics. With his son (William) Lawrence Bragg (1890 – 1971), he shared a 1915 Nobel Prize for research on the determination of crystal structures and Lawrence's discovery (1912) of the Bragg law of X-ray diffraction. The Bragg ionization spectrometer William designed and built is the prototype of all modern X-ray and neutron diffractometers; the two men used it to make the first exact measurements of X-ray wavelengths and crystal data.

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Scientist: Sir William Henry Bragg
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British physicist (1862–1942)

Bragg's father was a merchant seaman turned farmer. William Henry Bragg was born in Westwood in England and educated at a variety of schools before going as a scholar to Cambridge University. He graduated in 1884 and after a year's research under J. J. Thomson took the chair of mathematics and physics at the University of Adelaide, Australia, in 1886. He returned to England as professor of physics at Leeds University in 1909, moving from there to University College, London, in 1915.

In Australia, Bragg concentrated on lecturing and started original research late in life (in 1904). He first worked on alpha radiation, investigating the range of the particles. Later he turned his attention to x-rays, originally believing (in opposition to Charles Barkla) that they were neutral particles. With the observation of x-ray diffraction by Max von Laue, he accepted that the x-rays were waves and constructed (1915) the first x-ray spectrometer to measure the wavelengths of x-rays. Much of his work was on x-ray crystallography, in collaboration with his son, William Lawrence Bragg. They shared the Nobel Prize for physics in 1915.

During the war Bragg worked on the development of hydrophones for the admiralty. In some ways his most significant work was done at the Royal Institution, London, where he was director from 1923. Under James Dewar's directorship the research functions of the Royal Institution had virtually disappeared. Bragg recruited several young and brilliant crystallographers who shared with him a commitment to applying the new technique to the analysis of organic compounds. There was no reason to suppose there was much chance of success but as early as the 1920s Bragg was planning to investigate biological molecules with x-rays. His first attempts were made on anthracene and naphthalene in 1921.

Biography: Sir William Henry Bragg
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The English physicist Sir William Henry Bragg (1862-1942) was the founder of the science of crystal-structure determination by x-ray diffraction methods. He received the Nobel Prize in physics jointly with his son, William L. Bragg, in 1915.

William Henry Bragg was born on July 2, 1862, at Westward, Cumberland, England. He attended King's College, Isle of Man, and Trinity College, Cambridge, where he took honors in mathematics in 1884. A year later he became professor of mathematics and physics at the University of Adelaide, Australia. He married there.

In time Bragg turned to experimentation, and soon after W. C. Roentgen's momentous discovery of x-rays in 1895, Bragg set up and experimented with an x-ray tube. In the next few years he did basic work and published papers on radioactivity, the range of alpha-particles and their power to ionize gases, and the behavior of secondary electrons, particularly those produced by gammarays. This work led him to form his views on the nature of x-rays.

Bragg returned to England in 1908 as Cavendish professor of physics at Leeds. Four years later Max von Laue, W. Friedrich, and P. Knipping discovered the diffraction of x-rays by a crystal. Bragg, in a simple reinterpretation of Laue's elegant mathematical theory, looked upon the interaction as a reflection of the waves of a narrow incident beam from a large number of equally spaced parallel planes of atoms. The Bragg equation embraces both the corpuscular and wave theories of x-rays and relates the x-ray wavelength, the angle of reflection, and the spacing of the planes. Bragg immediately saw the importance of the discovery and was able, with his son, to determine the exact arrangement of atoms or ions in crystals of a variety of simple substances such as common salt, diamond, and copper. Previously the arrangements of atoms in the elements and their compounds were inferred by indirect chemical methods, partly dependent on molecular weights observed in the gaseous state or solution.

After World War I Bragg moved to London. First at University College and then as director of the Royal Institution, he was responsible for the spread of crystalstructure methods, and the sciences of metallurgy and mineralogy, both predominantly concerned with solids, were reborn. Physicists could calculate properties of solids on the basis of atomic positions in the ideal crystal. Interpretation now extends to the endless variety of less perfectly ordered structures which make up the world of fibers, polymers, liquid crystals, and other aggregates of atoms, ions, and molecules, including proteins, enzymes, viruses, and other materials of life.

Bragg was president of the Royal Society from 1935 to 1940. He was kind and fatherly, admirable in the Royal Institution Christmas Lectures for juveniles, and an interpreter of science to the general public. He died in London on March 12, 1942.

Further Reading

A brief but adequate biography and an account of Bragg's work is in Nobel Foundation, Nobel Lectures, Including Presentation Speeches and Laureates' Biographies: Physics, 1901-1921 (1967). His life and work are discussed in Bernard Jaffe, Chemistry Creates a New World (1957); George Gamow, Biography of Physics (1961); and R. Harré, ed., Scientific Thought (1969).

Additional Sources

Caroe, G. M., William Henry Bragg, 1862-1942: man and scientist, Cambridge; New York: Cambridge University Press, 1978.

Jenkin, John., The Bragg family in Adelaide: a pictorial celebration, Australia: University of Adelaide Foundation in conjunction with La Trobe University, 1986.

 
Columbia Encyclopedia: Sir William Henry Bragg
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Bragg, Sir William Henry, 1862-1942, English physicist, educated at King William's College, Isle of Man, and Trinity College, Cambridge. He served on the faculties of the Univ. of Adelaide in Australia (1886-1908), the Univ. of Leeds (1909-15), and the Univ. of London (1915-23). From 1923 he was Fullerian professor of chemistry in the Royal Institution and director of the Davy-Faraday research laboratory. He shared with his son W. L. Bragg the 1915 Nobel Prize in Physics for their studies, using the X-ray spectrometer, of X-ray spectra, X-ray diffraction, and of crystal structure. He became a Fellow of the Royal Society in 1906 and served as president of the society from 1935 to 1940. In 1920 he was knighted. Among his works are The World of Sound (1920), Concerning the Nature of Things (1925), An Introduction to Crystal Analysis (1929), and The Universe of Light (1933). With W. L. Bragg he wrote X Rays and Crystal Structure (1915, 5th ed. 1925).

Bibliography

See biography by Sir Kerr Grant (1952).

Wikipedia: William Henry Bragg
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Not to be confused with civil engineer/antiquarian William Bragge.
William Henry Bragg

Born 2 July 1862(1862-07-02)
Wigton, Cumberland, England
Died 10 March 1942 (aged 79)
London, England, United Kingdom
Residence United Kingdom
Nationality English
Fields Physicist
Institutions University of Adelaide

University of Leeds
University College London

Royal Institution
Alma mater Cambridge University
Academic advisors J. J. Thomson
Doctoral students W. L. Bragg
Kathleen Lonsdale
William Thomas Astbury
Other notable students John Burton Cleland
Known for X-ray diffraction
Notable awards Nobel Prize in Physics (1915)
Religious stance Anglican
Notes
He is the father of William Lawrence Bragg. Father and son jointly won the Nobel Prize.

Sir William Henry Bragg OM, KBE (2 July 1862 – 10 March 1942) was a British physicist, chemist, mathematician and active sporstman who uniquely[1] shared a Nobel Prize with his son William Lawrence Bragg - the 1915 Nobel Prize in Physics.

Contents

Biography

Early years

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 Old 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" in the mathematical tripos.[2][3][4]

University of Adelaide

In 1885, (at the age of 23), Bragg was appointed Elder Professor of Mathematics and Experimental Physics at the University of Adelaide,[5] and started work there early in 1886. 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.[4][3]

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. "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",[4] on "Some Recent Advances in the Theory of the Ionization of Gases". This idea was followed up "in a brilliant series of researches"[4] 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 a Rays and on the Classification of the a 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.[4][3]

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."[3]

Whilst in Adelaide, Bragg 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. He also met Gwendoline née Todd, a skilled water-colour painter, whom he married in 1889.[4][3] Their first son, William Lawrence, was born in North Adelide in 1890.

University of Leeds

Commemorative plaque on the Parkinson Building, University of Leeds

Bragg occupied the Cavendish chair of physics at 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, William Lawrence Bragg, then a research student at Cambridge, founded the new science of X-ray analysis of crystal structure.

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.[3]

In 1915 father and son were jointly awarded[1] 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.[3]

University College London

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.[3]

Royal Institution

From 1923 he was Fullerian professor of chemistry at the Royal Institution and director of the Day Faraday Research Laboratory.[6] This institution was practically rebuilt in 1929-30 and, under Bragg's directorship, many valuable papers were issued from the laboratory.[3]

Legacy

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.

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 William Lawrence Bragg.[7]

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 William Lawrence Bragg.

William H. Bragg was appointed Commander of the Order of the British Empire (CBE) in 1917, Knight Commander (KBE) in 1920, and was admitted to the Order of Merit in 1931.[3]

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.[3]

Timeline

  • 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 Todd 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 chair of physics
  • 1915-23 University College London - Quain Professor of physics
  • Royal Institution
    • Fullerian professor of chemistry
    • Director of the Day Faraday Research Laboratory
  • 1942 Died in London

Prizes

Publications

  • 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)

Further reading

  • "[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.

References

  1. ^ 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.
  2. ^ Bragg, William Henry in Venn, J. & J. A., Alumni Cantabrigienses, Cambridge University Press, 10 vols, 1922–1958.
  3. ^ 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. http://gutenberg.net.au/dictbiog/0-dict-biogBr-By.html#bragg1. Retrieved 2008-10-07. 
  4. ^ a b c d e f Tomlin, S. G. (1979). "Bragg, Sir William Henry (1862-1942)". Australian Dictionary of Biography. Australian National University. http://www.adb.online.anu.edu.au/biogs/A070396b.htm. Retrieved 2008-10-07. 
  5. ^ 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 UNIVERSITY OF ADELAIDE
    ELDER PROFESSOR OF MATHEMATICS AND EXPERIMENTAL PHYSICS
    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.
  6. ^ The Davy Faraday Research Laboratory
  7. ^ "Bragg Gold Medal for Excellence in Physics". Australian Institute of Physics. 2009. http://www.aip.org.au/content/bragg. Retrieved 2009-01-11. 

External links

v • d • e
Nobel Laureates in Physics

Wilhelm Röntgen (1901) · Hendrik Lorentz / Pieter Zeeman (1902) · Henri Becquerel / Pierre Curie / Marie Curie (1903) · Lord Rayleigh (1904) · Philipp Lenard (1905) · J. J. Thomson (1906) · Albert Michelson (1907) · Gabriel Lippmann (1908) · Guglielmo Marconi / Ferdinand Braun (1909) · Johannes van der Waals (1910) · Wilhelm Wien (1911) · Gustaf Dalén (1912) · Kamerlingh Onnes (1913) · Max von Laue (1914) · W. L. Bragg / W. H. Bragg (1915) · Charles Barkla (1917) · Max Planck (1918) · Johannes Stark (1919) · Charles Guillaume (1920) · Albert Einstein (1921) · Niels Bohr (1922) · Robert Millikan (1923) · Manne Siegbahn (1924) · James Franck / Gustav Hertz (1925)
v • d • e
Presidents of the Royal Society

William Huggins (1900) · John Strutt (1905) · Archibald Geikie (1908) · William Crookes (1913) · Joseph John Thomson (1915) · Charles Scott Sherrington (1920) · Ernest Rutherford (1925) · Frederick Gowland Hopkins (1930) · William Henry Bragg (1935) · Henry Hallett Dale (1940) · Robert Robinson (1945) · Edgar Adrian (1950) · Cyril Norman Hinshelwood (1955) · Howard Florey (1960) · Patrick Blackett (1965) · Alan Lloyd Hodgkin (1970) · Alexander R. Todd (1975) · Andrew Huxley (1980) · George Porter (1985) · Michael Atiyah (1990) · Aaron Klug (1995)

Robert May (2000) · Martin Rees (2005)

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