THE report of a joint committee of the Chemical Society, Faraday Society and Physical Society on symbols for thermodynamical and physico-chemical quantities and conventions relating to their use has been published. It contains symbols for use in thermodynamics and physical chemistry, with explanatory matter. The objects of the joint committee, it is stated, were to correlate the views of chemists and physicists with regard to the use of symbols for thermodynamic quantities and to deal similarly with symbols for other quantities which are of interest to both chemists and physicists. The committee was very representative, and the report, which is a document of sixteen pages, is of considerable interest. The symbols and conventions of the report have been adopted as recommended practice by the three societies responsible for it and by British Chemical Abstracts. Copies of the report may be obtained by non-members at 6d. per copy or 7s. 6d per 25 copies, post paid, from the Assistant Secretary, Chemical Society, Burlington House, Piccadilly, London, W.I.