Referee's report by William Edward Curtis, on a paper 'The hyperfine structure of the Zeeman components of the resonance lines of sodium' by Derek Ainslie Jackson and H Kuhn Sectional committee: Physics Recommended for publication in Proceedings. Some of the figures could be reduced in size. From an experimental point of view, the work is definite and a notable achievement in the field. [Published in Proceedings of the Royal Society A, 1938]. Endorsed on verso as received 28 April 1938. April 1938