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...