British physicist, known for her work in X-ray crystallography. She was the first woman to be elected a fellow of the Royal Society (in 1945) and was made a DBE in 1956.
Born Kathleen Yardley, the daughter of a postman in Newbridge, Ireland, she was educated at Bedford College, London, where she graduated in 1922. She then joined the research staff of the Royal Institution under Sir William Bragg and over the following twenty years, with such colleagues as Dorothy Hodgkin and J. D. Bernal, worked as an X-ray crystallographer. Her first major success came in 1929 with her publication of the structure of benzene. Lonsdale continued to work on the structure of a number of organic molecules, producing in 1948 a survey of the discipline in her Crystals and X-Rays.
As a Quaker, Lonsdale refused to register for employment at the outbreak of World War II. As the mother of three small children, she would have been exempt from any government service, but was fined £2 for refusing to register. She refused to pay and spent one month in Holloway prison. In 1948 Lonsdale moved to University College, London, where she became professor of crystallography (1948–68).
Subjects: Science and Mathematics — Contemporary History (Post 1945).