Referee's report by Robert Robertson, on a paper 'Investigations in the infra-red region of the spectrum - XI—The absorption spectrum and molecular structure of boron trichloride, and the effect of strain on plane groups of the type XY3' by A B D Cassie Sectional Committee: Physics Recommended for publication in the 'Proceedings of the Royal Society of London'. Criticises the choice of frequencies used and suggests this requires reconsideration. The paper requires experimental proof of the gaseous state at 430cm. [Published in the 'Proceedings of the Royal Society of London'] Endorsed on verso as received 31 July 1934. 28 July 1934