THE NATURE OF ENZYME ACTION. By W. M. BAYLISS, D.Sc., F.R.S. Third Edition. 5s. net. THE CHEMICAL CONSTITUTION OF THE PROTEINS. By R. H. A. PLIMMER, D.Sc. Part I.--Analysis. Second Edition, Revised and Enlarged. 5s. 6d. net. Part II.--Synthesis, etc. Second Edition, Revised and Enlarged. 3s. 6d. net. THE GENERAL CHARACTERS OF THE PROTEINS. By S. B. SCHRYVER, Ph.D., D.Sc. 2s. 6d. net. THE VEGETABLE PROTEINS. By THOMAS B. OSBORNE, Ph.D. 3s. 6d. net. THE SIMPLE CARBOHYDRATES AND THE GLUCOSIDES. By E. FRANKLAND ARMSTRONG, D.Sc., Ph.D. Second Edition, Revised and Enlarged. 5s. net. THE FATS. By J. B. LEATHES, F.R.S., M.A., M.B., F.R.C.S. 4s. net. ALCOHOLIC FERMENTATION. By A. HARDEN, Ph.D., D.Sc., F.R.S. Second Edition. 4s. net. THE PHYSIOLOGY OF PROTEIN METABOLISM. By E. P. CATHCART, M.D., D.Sc. 4s. 6d. net. SOIL CONDITIONS AND PLANT GROWTH. By E. J. RUSSELL, D.Sc. 5s. net. OXIDATIONS AND REDUCTIONS IN THE ANIMAL BODY. By H. D. DAKIN, D.Sc., F.I.C. 4s. net. THE SIMPLER NATURAL BASES. By G. BARGER, M.A., D.Sc. 6s. net. NUCLEIC ACIDS. THEIR CHEMICAL PROPERTIES AND PHYSIOLOGICAL CONDUCT. By WALTER JONES, Ph.D. 3s. 6d. net. THE DEVELOPMENT AND PRESENT POSITION OF BIOLOGICAL CHEMISTRY. By F. GOWLAND HOPKINS, M.A., M.B., D.Sc., F.R.S. THE POLYSACCHARIDES. By ARTHUR R. LING, F.I.C. COLLOIDS. By W. B. HARDY, M.A., F.R.S. RESPIRATORY EXCHANGE IN ANIMALS. By A. KROGH, Ph.D. PROTAMINES AND HISTONES. By A. KOSSEL, Ph.D. LECITHIN AND ALLIED SUBSTANCES. By H. MACLEAN, M.D., D.Sc. THE ORNAMENTAL PLANT PIGMENTS. By A. G. PERKIN, F.R.S. CHLOROPHYLL AND HAEMOGLOBIN. By. H. J. PAGE, B.Sc. ORGANIC COMPOUNDS OF ARSENIC AND ANTIMONY. By GILBERT T. MORGAN, D.Sc., F.I.C. LONGMANS, GREEN AND CO., LONDON, NEW YORK, BOMBAY, CALCUTTA, AND MADRAS. ALCOHOLIC FERMENTATION BY ARTHUR HARDEN, PH.D., D.SC., F.R.S. PROFESSOR OF BIOCHEMISTRY, LONDON UNIVERSITY HEAD OF THE BIOCHEMICAL DEPARTMENT, LISTER INSTITUTE, CHELSEA [Illustration: sailing ship in crown-like frame] /SECOND EDITION/ LONGMANS, GREEN AND CO. 39 PATERNOSTER ROW, LONDON FOURTH AVENUE & 30TH STREET, NEW YORK BOMBAY, CALCUTTA, AND MADRAS 1914 PREFACE. The following chapters are based on courses of lectures delivered at the London University and the Royal Institution during 1909-1910. In them an account is given of the work done on alcoholic fermentation since Buchner's epoch-making discovery of zymase, only in so far as it appears to throw light on the nature of that phenomenon. Many interesting subjects, therefore, have perforce been left untouched, among them the problem of the formation of zymase in the cell, and the vexed question of the relation of alcoholic fermentation to the metabolic processes of the higher plants and animals.