THE American Chemical Society has started a new venture in the form of a quarterly issue of Chemical Reviews. The first issue contains four articles: on “Atomic Weights and Isotopes” (40 pp.), by Prof. T. W. Richards; on “The Constitution of Polysaccharides” (31 pp.), by Principal J. C. Irvine; on “The Theory of Membrane Equilibria” (18 pp.), by Prof. F. G. Donnan, and on “Organic Radicals” (51 pp.), by Prof. M. Gomberg. These four articles were prepared in connexion with the dedication of the Sterling Chemical Laboratory, and are now published as part of the first volume of Chemical Reviews by permission of Yale University.