Bragg, William Lawrence

ENGLISH PHYSICIST
1890–1971

Sir William Lawrence Bragg was born on March 31, 1890, in Adelaide, South Australia, where his father, William Henry Bragg, was professor of mathematics and physics. Lawrence attended St. Peter's College, Adelaide, and studied mathematics at the university. The family moved to England in 1909, and Bragg continued his studies at Trinity College, Cambridge, taking first place in the natural sciences degree in 1912. He then began research studies at the Cavendish Laboratory and during 1912 and 1913, in conjunction with his father, he discovered how to use x rays to determine the molecular structure of crystals. Lawrence also determined Bragg's law, nλ = 2d sinθ the equation that links the wavelength of x rays with the distance between two crystal planes and the angle of incidence. For this work, one of the crucial discoveries of twentieth-century science, the Braggs were jointly awarded the Nobel Prize for physics in 1915; sharing the award at the age of twenty-five, Lawrence remains the youngest-ever winner of the esteemed prize.

During World War I, Bragg served in Flanders in a sound-ranging unit of the Royal Artillery. After demobilization he succeeded Ernest Rutherford as professor of physics at the University of Manchester. There he worked on problems such as the structure of silicates and of metals . After briefly directing the National Physical Laboratory, Bragg in 1938 became director of the Cavendish, once again succeeding Rutherford. At the Cavendish, Bragg established a major crystallographical research group despite some opposition from former members of Rutherford's group who wanted the laboratory to continue to concentrate on nuclear physics. Bragg held the laboratory together during the World War II years (1939–1945) and served on a number of government scientific committees; as a result of his efforts, he was knighted in 1941.

After the war Bragg established at the Cavendish Laboratory, with funding from the Medical Research Council, a unit for the study of molecular structure of biological systems. It was here in 1953 that Francis Crick (whom Bragg did not like) and James Watson determined the double helical structure of DNA . At the start of 1954 Bragg moved to the Royal Institution to try to repair the scientific capacity of the institution after it had been poorly managed by another scientist. Bragg was the only scientist of repute willing to take on this position, and it undoubtedly did him harm within the scientific community, especially the Royal Society .

Bragg revived the fortunes of the Royal Institution, both by increasing its public programs, especially its schools' lectures, and developing a major research group. This group included Max Perutz and John Kendew, who, working at both the Royal Institution and the Cavendish Laboratory, determined the structures of hemoglobin and myoglobin, for which they won the Nobel Prize for chemistry in 1962. Working with Bragg during the 1960s at the Royal Institution, David (later Lord) Phillips determined the structure of an enzyme, lysozyme, for the first time. On his retirement in 1966, Bragg was able to hand over a Royal Institution now in reasonably good shape to his successor George Porter. Bragg died five years later on July 1, 1971.

see also Bragg, William Henry; Rutherford, Ernest; Watson, James Dewey.

Frank A. J. L. James

Bibliography

James, Frank A. J. L., and Quirke, Viviane (2002). "L'affaire Andrade or How not to Modernise a Traditional Institution." In "The Common Purposes of Life": Science and Society at the Royal Institution of Great Britain, ed. Frank A. J. L. James. Aldershot, U.K.: Ashgate, pp. 273–304.

Phillips, David (1979). "William Lawrence Bragg." Biographical Memoirs of Fellows of the Royal Society of London 22:381–413.

Phillips, David, and Thomas, John Meurig, eds. (1990). Selections and Reflections: The Legacy of Sir Lawrence Bragg. Northwood, U.K.: Science Reviews.

Quirke, Viviane (2002). "'A Big Happy Family': The Royal Institution under William and Lawrence Bragg and the History of Molecular Biology." In "The Common Purposes of Life": Science and Society at the Royal Institution of Great Britain, ed. Frank A. J. L. James. Aldershot, U.K.: Ashgate, pp. 249–271.

Bragg, William Lawrence (1890–1970) An English physicist who, with his father William Henry Bragg, evolved the technique of X-ray crystallography, used to determine the atomic structure of crystals. He was an early supporter of the concept of continental drift, and is thought to have been responsible, in 1922, for arranging the translation into English and publication of Wegener's work. See also BRAGG'S LAW.