An X-ray diffraction camera can determine the molecular structures of crystals, a technique which eventually proved crucial for the understanding of complex molecules such as penicillin, insulin and DNA. This camera was used at the Royal Institution by John Desmond Bernal (1901-1971). Bernal founded the science of molecular biology and pioneered X-ray crystallography. He did important work on the structure of water while Professor of Physics at the University of London. During WWII he was involved in unsuccessful attempts to create artificial icebergs to act as aircraft carriers. He published 'The Social Function of Science' (1939) and 'The Origin of Life' (1967). Known to his friends as 'Sage', Bernal was very influential in both political and scientific circles.
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