Letter from William Hume-Rothery, on a paper 'The application of Boltzmann’s superposition theory to materials exhibiting reversible β flow' by C Henderson, to D C Martin, Assistant Secretary of the Royal Society Paper reference code: A174 Hume-Rothery has now shown Henderson's paper to his colleague and they both recommend the paper to published in the Proceedings, suggesting the first part of the paper be read by a mathematical physicist. Written from Inorganic Chemistry Lab, University Museum, Oxford [England]. [Published in Proceedings A, 1951]. Endorsed on recto as received 17 November 1950. 16 November 1950