Radical Woman of the Day: Kathleen Lonsdale

On this day in 1903 was born Dame Kathleen Lonsdale, crystallographer, who determined the molecular structure of benzene and hexachlorobenzene and was the first woman elected to membership in the Royal Society.

After transferring to a boys’ high school because the girls’ school she had been attending did not offer math and science courses, Lonsdale (born Kathleen Yardley) graduated with a Bachelor of Science degree from Bedford College for Women in 1922, then earned her Master’s Degree in physics from University College, London in 1924. She later earned a Doctor of Science degree from University College, London in 1936 while working as a researcher at the Royal Institution.

Both staunch pacifists, Lonsdale and her husband Thomas converted to Quakerism in 1935, and Lonsdale spent a month in prison during WWII for refusal to either register for civil defence duties or pay the fine for not registering.

In addition to discovering the structure of benzene and hexachlorobenzene, Lonsdale pioneered the use of X-rays in the study of crystals and in 1949 became a professor of chemistry and head of the Crystallography department at University College, London, where she was the first tenured female professor. Among other honors, she was elected President of the International Union of Crystallography in 1966 and President of the British Association for the Advancement of Science in 1967, a first for a woman in both instances. Lonsdaleite, a kind of diamond formed from meteorites, is named for her.

Via the Radical Women’s History Project.