By Mark M. Green (sciencefromaway.com)
Benzene with six carbon and six hydrogen atoms plays a critical industrial role, and is a theoretical model for understanding all of organic chemistry. Although the shape of this key molecule, proposed around 1860 as a hexagon of carbon atoms, has to be certainly known to understand these roles, for seventy years no experiment was capable of testing this prediction.
In 1903, along came Kathleen, one of the ten Yardley children of County Kildare, Ireland. In England, where her family moved when she was a child, Kathleen was directed to study “woman’s subjects.” But her brilliance could not be restrained and she was allowed to go to a boys’ school, as the only girl in the class, to study mathematics. She did so well that she was allowed to go to college. There she included physics in her studies against all advice, as not a woman’s subject. Again she was not to be contained. In 1922 she gained the highest marks of any student in the University’s BSc exams including the highest marks seen in ten years of students’ exams. One of her examiners was a famous physicist, W. H. Bragg. He immediately saw her potential for scientific work and interested her in his focus on X-ray analysis, a method to determine the shapes of molecules. Bragg suggested that she might look at small organic molecules but said no more. Benzene and molecules derived from it are such small molecules.
Not long after working with Bragg, Kathleen met Thomas Lonsdale who was an engineering student at University College London. They married in 1927 and it appears that Kathleen decided that she should devote herself to family life: they had three children in relatively close progression. As any mother will tell you, three under the age of five is quite a handful. However, Thomas Lansdale did not hold common opinions of the time. He insisted that he had married a scientist as well as a mother and encouraged her to continue her work. In an account of her life by the Royal Society is a description of their early life together: “In the evenings Thomas did experiments in the kitchen for his PhD, while Kathleen did her calculations by hand.” The calculations, based on her X-ray experiments, were, in part, devoted to proving that benzene is in fact hexagonal. She continued her work with great success and in 1945 was one of the only two women ever offered membership in the Royal Society up to that time.
In spite of all her scientific accomplishments, Kathleen Lonsdale spent a month in prison at the onset of World War II, washing floors and cleaning toilets, for refusing to register for war service and refusing to pay the £2 fine for not registering. She and her husband, several years before, had become Quakers and she believed in acting strongly on pacifist beliefs. These beliefs affected her actions until the end of her life. She was also a strong proponent of the role of women in science holding the view that society has to make special provisions to allow professional women their role as mothers.
Perhaps we have reached a point now, in 2015, when her views are widely held. But this was certainly not the situation shortly before she died. I well remember, as a young professor in 1969 at the University of Michigan, recommending a brilliant young woman for acceptance to the graduate chemistry program at Cornell and receiving a letter in response appreciating my view, but noting that all acceptable male applicants are taken before a woman is admitted.