||This article includes a list of references, but its sources remain unclear because it has insufficient inline citations. (November 2012)|
Lonsdale in 1968
28 January 1903
Newbridge, County Kildare, Ireland
|Died||1 April 1971
|Institutions||University College London
University of Leeds
|Alma mater||Bedford College for Women
University College London
|Doctoral advisor||William Henry Bragg|
|Known for||X-ray crystallography|
|Notable awards||Davy Medal (1957)|
Dame Kathleen Lonsdale, DBE FRS (née Yardley) (28 January 1903 – 1 April 1971) was a crystallographer, who finally proved that the benzene ring was flat by X-ray diffraction methods in 1929. She was the first to use Fourier spectral methods while solving the structure of hexachlorobenzene in 1931. During her career she attained a number of firsts for a woman scientist, including one of the first two women elected a Fellow of the Royal Society in 1945 (along with Marjory Stephenson), first woman tenured professor at University College London, first woman president of the International Union of Crystallography, and first woman president of the British Association for the Advancement of Science.
Early life and education 
She was born Kathleen Yardley at Newbridge, County Kildare, Ireland, the tenth child of Harry Yardley, the town postmaster, and Jessie Cameron. Her family moved to Seven Kings, Essex, England, when she was five years old because of political unrest. She studied at Woodford County High School for Girls, then transferred to Ilford County High School for Boys to study mathematics and science, because the girls' school did not offer these subjects.
Marriage and family 
After beginning her research career, in 1927 Yardley married Thomas Jackson Lonsdale. They had three children – Jane, Nancy, and Stephen. The son became a medical doctor and worked for several years in Malawi.
Though she had been brought up in the Baptist religion as a child, Kathleen Lonsdale became a Quaker in 1935, simultaneously with her husband. Already committed pacifists, both were attracted to Quakerism for this reason. She served a month in Holloway prison during the Second World War because she refused to register for civil defence duties, or pay a fine for refusing to register. In 1953 at the annual meeting of the British Quakers, she delivered the keynote Swarthmore Lecture, under the title Removing the Causes of War.
In 1924, she joined the crystallography research team headed by William Henry Bragg at the Royal Institution. After her marriage, Lonsdale worked at the University of Leeds in the late 1920s. During the early 1930s, she cared for her small children nearly full-time.
In 1934, Lonsdale returned to work with Bragg at the Royal Institution as a researcher. She was awarded a DSc from University College London in 1936 while at the Royal Institution. In addition to discovering the structure of benzene and hexachlorobenzene, Lonsdale worked on the synthesis of diamonds. She was a pioneer in the use of X-rays to study crystals. Lonsdale was elected as one of the first two women Fellows of the Royal Society in 1945 (the other was the biochemist Marjory Stephenson).
In 1949, Lonsdale became a professor of chemistry and the head of the Department of Crystallography at University College, London. She was the first tenured woman professor at that college, a position she held until 1968 when she was named Professor Emeritus.
Legacy and honours 
- 1956, she was given the title Dame Commander of the Order of the British Empire.
- 1966, she was elected as the first woman president of the International Union of Crystallography.
- 1967, active in encouraging young people to study science, she was elected as the first woman president of the British Association for the Advancement of Science.
- A Kathleen Lonsdale Building is named in her honour at both University College London, UK and University of Limerick, Ireland.
- 1969, she was awarded an Honorary Degree (Doctor of Science) by the University of Bath.
- Lonsdaleite, an allotrope of carbon, was named in her honour; it is a rare form of diamond found in meteorites.
Lonsdale died on 1 April 1971 from an anaplastic cancer of unknown origin.
Selected writings 
- "The Structure of the Benzene Ring in Hexamethylbenzene," Proceedings of the Royal Society 123A: 494 (1929).
- "An X-Ray Analysis of the Structure of Hexachlorobenzene, Using the Fourier Method," Proceedings of the Royal Society 133A: 536 (1931).
- Simplified Structure Factor and Electron Density Formulae for the 230 Space Groups of Mathematical Crystallography, G. Bell & Sons, London, 1936.
- "Diamonds, Natural and Artificial," Nature 153: 669 (1944).
- "Divergent Beam X-ray Photography of Crystals," Philosophical Transactions of the Royal Society 240A: 219 (1947).
- Crystals and X-Rays, G. Bell & Sons, London, 1948.
- Removing the Causes of War, 1953.
- Gill Hudson, Lonsdale , Dame Kathleen (1903–1971), Oxford Dictionary of National Biography, Oxford University Press, 2004; online edn, Sept 2010, accessed 6 Nov 2012
- "Honorary Graduates 1966 to 1988 | University of Bath". Bath.ac.uk. Retrieved 31 October 2012.
- Childs, Dr. Peter E. (20 April 1998). "The Life and Work of Dame Kathleen Lonsdale (1903-1971)". University of Limerick. Retrieved 2012-10-20. A lecture to mark the official opening of the Kathleen Lonsdale Building, University of Limerick.
- Hodgkin, Dorothy M. C. (1975). "Biographical Memoirs of Fellows of the Royal Society: Kathleen Lonsdale. 18 January 1903 - 1 April 1971" (PDF). Royal Society. Retrieved 2012-10-20. Biogr. Mems Fell. R. Soc. 1975 21, 447-484. doi: 10.1098/rsbm.1975.0014
- Staff (2004). "Kathleen Lonsdale". Encyclopedia of World Biography. Retrieved 2012-10-20. Or see alternative source.
- Staff (January 2003). "Chemistry World: Woman of substance". Royal Society of Chemistry (UK). Retrieved 2012-10-20.
- Staff. "Kathleen Yardley Lonsdale 1903-1971". CWP at University of California. Retrieved 2012-10-20. Derived from the Dictionary of Scientific Biography.
- Staff. "Papers and correspondence of Dame Kathleen Lonsdale, 1903-1971". Archives Hub. Retrieved 2012-10-20. An overview of the scope and content of the collection of Lonsdale's papers that are kept at University College London.
- Reville, William (2004). "Kathleen Lonsdale - Famous Irish Scientist". University College Cork. This article first appeared in The Irish Times, 13 December 2001.
- Archival material relating to Kathleen Lonsdale listed at the UK National Archives