Systematic organic chemistry: Modern methods of preparation and estimation. By W. M. cumming, D.Sc., I. Vance Hopper, Ph.D., and T. Sherlock Wheeler, Ph.D., B.Sc. Second edition revised by W. M. Cumming and I. Vance Hopper, Pp. xxiv + 555. London: Constable & Co., 1931. 25s