Referee's report by Arthur Schuster, on a paper 'The problem of finite focal depth revealed by seismometers' by George Walker Walker Sectional Committee: Mathematics Recommended for publication in the 'Proceedings of the Royal Society of London'. The reasons the author gives for publication in the Philosophical Transactions are not considered sufficient. Thinks the paper will be 'difficult to follow by any one who has not an intrinsic knowledge of the previous literature'. [Published in the Philosophical Transactions of the Royal Society A, 1922] Endorsed on verso as received 20 April 1921. [April 1921]