“we’ve all agreed that we must come”: Gann and Witkowski 2010.

she discovered that DNA occurred: An excellent description of Franklin’s work can be found in Klug 1968a, with some clarifications in Klug 1968b and additional information in Klug 1974. Elkin 2003 presents a historical perspective, and Braun, Tierney, and Schmitzer 2011 give a pedagogical explanation of the technical work.

she absolutely refused to assume: According to Klug 1968a, Franklin’s antihelical attitude around May 1952 resulted from her uncertainty about the survivability of the helical structure in the A form of DNA. Her general reluctance to assume anything about the structure is reflected in her statement “No attempt will be made to introduce hypotheses concerning details of structure at the present stage” (Franklin and Gosling 1953a).

“He [Watson] just wanted the answer”: Crick 1988, p. 69.

Elwyn Beighton in Astbury’s lab: Beighton’s 1951 photograph of DNA is in the Special Collections, Astbury Papers, C7, at the University of Leeds. The photographs can be seen online at www.leeds.ac.uk/heritage/Astbury/Beighton_photo/index.html.