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Lonsdale, Kathleen (1903–1971)

Lonsdale, Kathleen (1903–1971)

Irish-born crystallographer and pacifist who was one of the first two women to be elected a fellow of the Royal Society, and first woman president of the British Association for the Advancement of Science. Born Kathleen Yardley on January 28, 1903, in Newbridge, County Kildare, Ireland; died in University College Hospital, London, England, on April 1, 1971; daughter of Harry Frederick Yardley (a postmaster) and Jessie (Cameron) Yardley; attended Ilford County High School for Girls; Bedford College for Women, London University; married Thomas Jackson Lonsdale, in 1927; children: Jane Lonsdale (b. 1929); Nancy Lonsdale (b. 1931); Stephen Lonsdale (b. 1934).

Had research appointments at University College, London and the Royal Institution (1922–27); was Amy Lady Tate Scholar at Leeds University (1927–29); became a Quaker (1935); was a Leverhulme Research Fellow (1935–37); was a Dewar Fellow at the Royal Institution (1944–46); elected fellow of the Royal Society (1945); was a special fellow of the U.S. Federal Health Service (1947); was a professorof chemistry and head of the department of crystallography, University College, London (1949–68); was a member of a Quaker delegation to the Soviet Union (1951); delivered Swarthmore Lecture, "Removing the Causes of War" (1953); was president of the British section of the Women's International League for Peace and Freedom; awarded DBE (1956); awarded the Royal Society's Davy medal (1957); was vice president (1960–66) and president (1966) of the International Union of Crystallography; served as president of the British Association for the Advancement of Science (1968).


Simplified Structure Factor and Electron Density Formulae for the 230 Space-Groups of Mathematical Crystallography (1936); Crystals and X-rays (1949); (with N.F.M. Henry) International Tables for X-ray Crystallography (vol. I, 1952); ed. Quakers visit Russia (1952); Prisons for Women (1952); Security and Responsibility (1952); Removing the Causes of War (1953); Is Peace Possible? (1957); (with J. Kasper) International Tables for X-ray Crystallography (vol. II, 1959); (with C.H. MacGillavry and G.D. Rieck) International Tables for X-ray Crystallography (vol. III, 1962); I Believe … (1964). Also many articles on scientific, humanitarian and religious topics.

As a young girl living in London during the Great War, Kathleen Lonsdale was witness to both the vast strides made by science since the beginning of the century, and its potential for devastation and death. Born, as she often remarked, in the year in which the Wright brothers built and flew the first airplane, in 1916 Lonsdale found herself the target of bombing raids by German Zeppelins, and was disturbed by the implications of war not only for its innocent victims but also for its perpetrators. "We sometimes watched them being shot down in flames," she recalled 40 years later in her pacifist manifesto, Is Peace Possible?, "and my mother cried, because she had read that some of the German crews were boys of 16. Somehow this seemed to have very little connection with the science I was learning, but it may have had something to do with my own growing feeling that war was utterly wrong." Later, as one of the leading British scientists of her generation, Lonsdale confronted science's potential for evil as well as good and, as a Quaker and a pacifist, sought to convince politicians and the public of the virtues of disarmament, of nonviolent resistance, and of the settlement of disputes on the basis of justice rather than by armed force.

Born in 1903 in the small Irish town of Newbridge, County Kildare, Kathleen Lonsdale was the youngest of ten children of Jessie Cameron Yardley and Harry Frederick Yardley. Her English father had been a postal worker and a soldier and, on leaving the army, became postmaster at Newbridge, close to the Curragh military camp. An intelligent and widely read man, he was also quarrelsome, miserly, and sometimes drank heavily. In later years, he lived apart from his family, retired early due to ill health, and died when his youngest daughter was 20. He was clearly a rather distant parent, and the adult Kathleen wrote somewhat wistfully of her relationship with him. "I think he was fond of us and did not know how to show it. I wish that I could have been fonder of him. I think that it was from him that I inherited my passion for facts." Jessie Yardley, however, played a much greater part in the lives of her children. A lively and strong-minded woman of Scottish descent, she had been brought up in London, where she had picked up many Italian and music-hall songs which in old age she sang to herself. She had worked as a waitress and as a cutter in a shirt factory, and was a devout Baptist who brought up her children in her own faith. The Yardleys were poor, at times extremely so, and of the six children who survived, all but the youngest, Kathleen, had to leave school as early as possible in order to supplement the family income. The eldest brother, Fred Yardley, seems to have shared his sister's scientific bent. Unable to continue his education because of poverty, he became one of the first wireless operators, and in 1912 picked up the last signals from the sinking Titanic.

Lonsdale received her first formal education in the local school at Newbridge, and, after the family moved back to England in 1908, in the elementary school at Seven Kings in Essex. She quickly showed herself to be an exceptionally able pupil, and in 1914 she was awarded a county minor scholarship to the County High School for Girls at Ilford. Because physics, chemistry, and higher mathematics were not included on the curriculum there, she attended classes in these subjects at the County High School for Boys, the only girl to do so at that time. In 1919, she won a further scholarship, as well as a medal awarded by the Royal Geographical Society for the highest marks in geography and physical geography in the Cambridge Senior Local Examination and, at the early age of 16, entered Bedford College for Women in London. Initially, she chose to read mathematics, but at the end of her first year changed to physics, reportedly because she feared that the only career open to her as a mathematics graduate would be teaching, and because she was attracted by the experimental aspects of physics. A brilliant student, she also involved herself in student social life, was secretary to the Music Society, and coxed the college eight. In 1922, she graduated first in her class in the B.Sc. examination with the college's highest marks in ten years, and was recruited by Sir William Bragg to join his research team working on the structure of organic crystals, first at University College, London, and later at the Royal Institution.

There is such a thing as moral strength and moral leadership which does not depend upon the possession of hideously destructive weapons.

—Kathleen Lonsdale

Winner with his son of the 1915 Nobel Prize for physics, Bragg was a leader in the field of radioactivity and founder of the modern science of crystallography. By using ionization and by studying glancing reflections at the face of the crystal, he had greatly improved on Max Von Laue's 1912 demonstration of the diffraction of X-rays by the atoms of a crystal. However, although X-ray diffraction methods had been used to determine the arrangement of atoms in the crystalline forms of a few chemical substances, considerable difficulties still remained in the process of determining crystal structures. As part of Bragg's team, Lonsdale was one of an international group of research students who collaborated on scientific work and spent their free time together, playing table tennis or discussing a wide range of contemporary issues. Years later, she described the exhilaration and optimism of that period which, politically as well as professionally, seemed so full of promise.

When I became a research student, training under Sir William Bragg in the very place where Sir Humphry Davy, Michael Faraday, John Tyndall, Sir James Dewar, and other world-famous scientists had carried out their researches, the war was over and, as we thought, won. We genuinely hoped for a peace settlement that would end all war. … Meanwhile my work was fun. I often ran the last few yards to the laboratory.

She found Bragg an inspirational teacher, who left her completely free to follow her own line of research. Two years after joining his team, in 1924, she made her first major contribution to crystallography when, together with W.T. Astbury, she published "Tables for the Determination of Space Groups." In 1927, the same year in which she married Thomas Lonsdale, a fellow student at University College, Kathleen took up a research appointment at Leeds University, where she worked on what she herself regarded as the most fundamental of her researches. This was the discovery of the structure of the hexamethylbenzene molecule: by analyzing the structures of crystals of hexamethyl-benzene and hexachlorobenzene, she found that the benzene ring consisted of a flat regular hexagon of the six carbon atoms with the other six carbon atoms of attached methyl groups coplanar with the ring.

According to her friend and colleague Dorothy Hodgkin , Lonsdale did contemplate giving up scientific research at the time of her marriage "and settling down to become a good wife and mother." Her husband, however, dissuaded her. "He had not married, he said, to get a good housekeeper" and, indeed, throughout their life together Kathleen was to find in Thomas an invaluable emotional and practical support. Nevertheless, in the short term, marriage and particularly motherhood did pose their own problems: much of her work during her time at Leeds and following the Lonsdales' return to London in 1929 was carried out at home and even in the nursing homes where her children were born.

In 1931, Bragg, having obtained for her an allowance to pay for home help, invited her to return to the Royal Institution as his research assistant. She was to remain there for the next 15 years, until in 1946 she turned towards academic work with her appointment as reader in crystallography and, in 1949, professor of chemistry and head of the department of crystallography at University College. During her time at the Royal Institution, she was engaged in a range of researches: finding that there was no X-ray equipment that she could use, she instead took advantage of the offer of a big electromagnet, on which over the next ten years she made measurements of diamagnetic anisotropy, in the course of which she provided experimental verification of the postulated delocalization of electrons and the existence of molecular orbitals. She also investigated thermal diffuse reflections and was interested both in X-ray work at different temperatures and the thermal motion of atoms in crystals, and in ways of investigating the texture of crystals.

At University College, while maintaining and widening her research interests, she was also responsible for teaching and for the development both of new undergraduate and graduate courses and of her own research school. In 1946, she became general editor of the International Tables for X-ray Crystallography, a task which entailed a huge amount of work. Although this curtailed her research activities, she continued investigations into synthetic diamonds, writing a number of papers on the subject, and giving her name to the hexagonal diamond found in meteorites and now known as lonsdaleite. Further projects arose out of her desire to apply X-ray crystallography to the field of medical research. She initiated work on methonium compounds and on endemic bladder stones, this last prompted by a visit in 1962 from the chief medical officer of the Salvation Army, who had observed the incidence of stones among patients in certain underdeveloped countries, notably India. She was to continue this work even after her retirement in 1968, and was in fact still engaged on it at the time of her death.

As a scientist, Lonsdale found herself reacting against the strict fundamentalist Baptist faith of her mother. Her search for an alternative spiritual home ended when in 1935 she joined the Society of Friends (Quakers). With her husband, who also became a member of the Society, she became aware of relief efforts operated by the Quakers among the unemployed in South Wales, and later opened her home to refugees from Hitler's Germany sent to her by Friends' relief organizations. Combined with her existing concerns about international political developments and the responsibilities of science, Lonsdale's conversion to Quakerism served to confirm her loathing of militarism, a stand which on the outbreak of war in 1939 was to confront her with a dilemma. Compelled by law to register for employment and for civil-defense duties, she refused to do so as a conscientious objector, although she was in fact already doing voluntary work and would in any case have been exempted as the mother of young children. Declining to pay the small fine imposed for this offense, she was committed to jail for a month. In addition to doing normal prison work, she asked for, and was allowed to have in her cell scientific papers and instruments with which to continue her researches, and at the end of her term told the governor that she had managed to do "about seven hours each day of really concentrated scientific work." Lonsdale went on to suggest improvements in the treatment of prisoners and in prison conditions. She maintained her interest in this subject and in

1949 was appointed a prison visitor at a female institution, going on in 1961 to become deputy chair of the Board of Visitors of Bullwood Hall Borstal Institution for Girls. Visiting Russia in 1951, she toured a prison and impressed the governor, who did not know her past history, by her intensive knowledge of the penal system.

The early 1940s were a period of considerable change in Kathleen Lonsdale's life. Her term in Holloway Prison was described by her husband as the single most formative experience of her career, while the death in 1942 of her mentor, Sir William Bragg, coincided with a growing recognition of her own status in the field of crystallography. In 1943, the year of her imprisonment, she received the first of many invitations to participate in scientific meetings abroad, this one appropriately in her country of birth. Her lectures at the Institute of Advanced Studies Summer School in Dublin were attended not only by leading scientists such as Max Born, P.P. Ewald and Erwin Schrodinger, who chaired the conference, but also by the taoiseach (prime minister) of the now-independent Irish Free State, Eamon de Valera. In 1945, she became one of the first two women (with Marjory Stephenson ) to be elected fellow of the Royal Society. Other honors included her creation in 1956 as a Dame Commander of the Order of the British Empire and the award of the Royal Society's Davy Medal in 1957. In 1968, Dame Kathleen Lonsdale became first woman president of the British Association for the Advancement of Science, and in her presidential address to the association touched on a number of the issues which had preoccupied her throughout her career: these included the uses of science and technology, the arms trade, and the responsibility which scientists held for the uses to which their discoveries were put.

As a pacifist during the years of the Cold War, Lonsdale continued to campaign for disarmament and international co-operation, serving as president of the Women's International League for Peace and Freedom and as a member of the East-West Committee of the Society of Friends. In 1951, she visited Russia as part of a delegation of Friends which met representatives of the Soviet Peace Committee, leaders of the Baptist and Orthodox churches, and Jacob Malik, deputy foreign minister of the Soviet Union. In 1952, she edited the report of this delegation, and in 1957 produced her own justification of pacifism. Is Peace Possible?, aimed at a general audience, warned of the dangers of nuclear weapons and sought total disarmament and the establishment of "an impartial and objective World Court of Justice as a body to which all international disputes or grievances involving nations or governments can be referred." Citing Martin Luther King, Jr.'s civil-rights campaign, she demonstrated the power of nonviolent protest and the ability of individuals to resist community evil by such methods. She also identified population growth as a major threat to world peace as well as to health and living standards, while admitting the necessity of allowing countries such as China to develop their own response to this problem and pressing for increased aid from developed nations to disadvantaged areas in order to improve agricultural methods and to increase food supply.

The record of Kathleen Lonsdale's travels makes clear the extent to which her scientific, social, and religious concerns were interlinked: as Judith Milledge remarked, "she seldom … undertook a journey for one purpose without managing also to further the other." In 1954, for instance, she embarked on a two-month journey around the world, initially at the invitation of Australian Methodists and Friends, during which she delivered lectures "on crystallography, science and religion, pacifism and peacemaking, scientists' responsibilities, right use of science in general and atomic energy in particular, etc." Other travels during these years, both on scientific and humanitarian missions, included visits to the United States, Japan (where she received a particularly enthusiastic welcome for her own efforts on behalf of peace), Australia and New Zealand, India, the Far East, the People's Republic of China and in 1966 the Soviet Union again, for the meeting in Moscow of the Assembly of the International Union of Crystallography, which she chaired.

Lonsdale maintained her exceptionally heavy workload almost to the end of her life. A bad sleeper, she often woke at 4:30 and rose at 5:30 am and, after moving with her husband to live on the coast in 1965, had a daily five-hour journey to and from her laboratory in London, although she said the inconvenience was worthwhile. Admitted to hospital in December 1970, she accepted with equanimity the news that she was suffering from cancer. She spent the final weeks of her life trying to complete a book on her work on stones; the nurses who came to call her in the morning frequently found her already awake and at work. She died in University College Hospital on April 1, 1971.

In a discussion on the shortage of women in science written towards the end of her career, Kathleen Lonsdale outlined her own recipe for success:

For a woman, and especially a married woman with children, to become a first-class scientist, she must first of all choose, or have chosen, the right husband. … Then she must be a good organiser and be pretty ruthless in keeping to her schedule, no matter if the heavens fall. She must be able to do with very little sleep, because her working week will be at least twice as long as the average trades unionist's. She must go against all her early training and not care if she is regarded as a little peculiar. She must be willing to accept additional responsibility, even if she feels that she has more than enough. But above all, she must learn to concentrate in any available moment and not require ideal conditions in which to do so.

Confounding the obstacles implied here, Kathleen Lonsdale became an acknowledged leader in her field: Dorothy Hodgkin recalled her first sight of Lonsdale's paper on the structure of hexamethylbenzene, published in 1929, and "the marvelling pleasure with which I read her very definite conclusions." Not the least of her achievements was the role which she played in the development of her subject. Although, according to Milledge, who was one of her postgraduate students, she was not really a good teacher to the majority who did not share her intellectual capacity, she took an active interest in the training of crystallographers and in popularizing science through many broadcasts, lectures, and articles aimed at non-specialist audiences. She helped to found the Young Scientists' section of the British Association, and was conscious of the need to stimulate interest in science among students at every level. "Never," she reminded herself, "refuse an opportunity to speak at schools," and her last public engagement was, in fact, at a prize giving at Hastings High School for Girls. But her true greatness lies in her insistence on the moral responsibility not only of the scientist but of every individual to seek new ways of dealing with conflict in an era of unparalleled technological advance. An idealist but not an innocent, she accepted the difficulties and dangers involved in the search for peace, freedom, and justice, while never losing confidence in the validity of her own creed that "a life of non-violence is essentially one of spiritual out-reach to the good in other men and of belief that, even if there is no response, even if we appear to fail, goodness will in the end prevail."


Dictionary of National Biography 1971–1980. Oxford: Oxford University Press, 1986.

Hodgkin, D.M.C. "Kathleen Lonsdale," in Biographical Memoirs of Fellows of the Royal Society, 1975. Vol. 21. London: Royal Society, 1975, pp. 447–484.

Lonsdale, Kathleen. Is Peace Possible? London: Penguin, 1957.

Milledge, H.J. "Kathleen Lonsdale," in Acta Crystallographica. Vol. A31. Copenhagen: Munksgaard-International Union of Crystallography, 1975, pp. 705–708.

The Times obituaries, 1971–1975. Reading: Newspaper Archive Developments, 1978.

suggested reading:

Ewald, P.P., ed. Fifty years of X-Ray diffraction. 1963.

Rosemary Raughter , freelance writer in women's history, Dublin, Ireland

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