Referee's report by George Ingle Finch, on a paper 'Neutron diffraction' by G E Bacon and J Thewlis Sectional Committee: Physics Recommended for publication in the 'Proceedings of the Royal Society of London'. The paper might possibly be suitable for the Physical Society. The work has no experimental background, but the paper is clear and apparently valid, with many potential applications. [Published in the 'Proceedings of the Royal Society of London'] No received date. [1948]