What specific degree did Rosalind Franklin earn from Cambridge in 1945?

Rosalind Franklin earned a PhD in physical chemistry from Cambridge in 1945. Her doctoral research examined the physical chemistry and structure of coal, rather than DNA, the subject with which she is most often associated today.

Franklin studied chemistry within the Natural Sciences Tripos at Newnham College, Cambridge, graduating in 1941. She then researched coal at the British Coal Utilisation Research Association during the Second World War. By studying coal’s pores and how substances moved through them, she contributed to wartime knowledge relevant to fuel and gas-mask materials.

Her thesis was titled “The physical chemistry of solid organic colloids with special reference to coal.” This explains why “PhD in physical chemistry” is the best answer, while “PhD in physics” is a tempting but incorrect mix-up. Franklin’s later work used physical chemistry and X-ray crystallography to investigate DNA, viruses, graphite, and other materials.

Cambridge’s degree system also creates a minor historical wrinkle: women were not awarded titular BA and MA degrees there in the modern way until later. Franklin’s doctorate, however, was awarded in 1945.