'Where are your intelligent mothers to come from?': marriage and family in the scientific career of Dame Kathleen Lonsdale FRS (1903-71).

Although she was one of the most successful female scientists in twentieth-century Britain, the X-ray crystallographer Kathleen Yardley Lonsdale (1903-71) has received relatively little attention from historians of science. This paper, based on material from the recently opened Dame Kathleen Lonsdale Papers, argues that Lonsdale's scientific career was shaped in particular ways by her identity not just as a woman, but as a married woman and a mother. When interacting with her scientific colleagues, Lonsdale frequently had to confront the assumption that married women should not pursue scientific careers, an attitude shaped by British concerns about reasserting traditional gender roles after the World Wars I and II. Furthermore, although Lonsdale's husband, Thomas, was an ardent supporter of her career, in the early 1930s Lonsdale left research temporarily to care for her small children. Her desire to work from home during this period led her to pursue one of her most significant scientific projects: the creation of crystallographic reference tables. Lonsdale's own experiences, and those of her female students, led her to focus on issues of marriage and family when she began speaking and writing about women in science during the late 1960s.