Referee's report by unknown referee, on a paper 'The visual perception of fine detail' by Hamilton Hartridge Sectional committee: Physiology Recommended for publication in Philosophical Transactions. Most of the theories and results have already been published by the author in various publications. The optical arguments should be critically examined by a physicist. The author's use of pigments rather than pure spectral stimuli is open to criticism. The opinion of a statistician would be valuable in checking the cluster formation. There are some verbal errors that should be fixed. [Published in Philosophical Transactions B, 1947]. Date received not given. 1946