during the Second World War because she refused to register for civil defence duties, or to pay a fine for refusing to register. During this time she experienced a range of issues which would eventually result in Lonsdale becoming a prison reform activist and she joined the Howard League for Penal Reform. "What I was not prepared for was the general insanity of an administrative system in which lip service is paid to the idea of segregation and the ideal of reform, when in practice the opportunities for contamination and infection are innumerable, and those responsible for re-education practically nil" In 1953, at the Yearly Meeting of the British Quakers, she delivered the keynote Swarthmore Lecture, under the title Removing the Causes of War. A self-identified Christian pacifist, she wrote about peaceful dialogue and was appointed the first secretary of Churches' Council of Healing by the Archbishop of Canterbury William Temple. Death Lonsdale died on 1 April 1971, aged 68, from an anaplastic cancer of unknown origin. Legacy and honours Kathleen Lonsdale was elected an Honorary Member of the Women's Engineering Society in 1946 in recognition of her "brilliant and important work". 1956, she was made 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. There are buildings named in her honour at University College London, at the University of Limerick, and at Dublin City University. 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 harder form of diamond found in meteorites. A plaque was erected on Lonsdale's family home in Newbridge by the National Committee for Commemorative Plaques in Science and Technology in 2003, 100 years after her birth. On 1 April 2021, English Heritage unveiled a blue plaque at her childhood home in 19 Colenso Road, Seven Kings, London where she lived from 1911 to 1927, aged 8–24. The Kathleen Lonsdale room at Friends House, London, UK is named after her. References External links Lonsdale Papers at University College London Science in the Making Kathleen Lonsdale's papers in the Royal Society's archives Lonsdale's crystallographic models in the