Contents:—History of Gold—Properties of Gold—Compounds of Gold—Alloys of Gold—Occurrence of Gold in Nature: Gold Ores—Extraction of Gold from its Ores: Gold Washing—Treatment of Gold Ores by Crushing and Amalgamation—Treatment of Gold Ores by Wet Methods—Silver and its Alloys—Compounds and Ores of Silver—The Extraction of Silver from its Ores—Refining Gold and Silver—The Assay of Gold and Silver Ores—The Assay of Gold and Silver Bullion—Minting—Manufacture of Gold and Silver Wares—Platinum—Production and Consumption of the Precious Metals.

AGRICULTURE

SOILS AND MANURES. By J. Alan Murray, B.Sc. Demy 8vo. 6s. net.

Contents:—Preface. Chapter I.—Introductory. Chapter II.—The Origin of Soils. Chapter III.—Physical Properties of Soils. Chapter IV.—Chemistry of Soils. Chapter V.—Biology of Soils. Chapter VI.—Fertility. Chapter VII.—Principles of Manuring. Chapter VIII.—Phosphatic Manures. Chapter IX.—Phospho-Nitrogenous Manures. Chapter X.—Nitrogenous Manures. Chapter XI.—Potash Manures. Chapter XII.—Compound and Miscellaneous Manures. Chapter XIII.—General Manures. Chapter XIV.—Farmyard Manure. Appendices.—I. Valuation of Manures; II. Composition and Manurial Value of Various Farm Foods. Index.

BOTANY

PLANT PHYSIOLOGY AND ECOLOGY. By Frederic Edward Clements, Ph.D., Professor of Botany in the University of Minnesota. With 125 Illustrations. Demy 8vo. 10s. 6d. net.

TIMBER. By J. R. Baterden, Assoc.M.Inst.C.E. Profusely Illustrated from Photographs and Diagrams. Extra Crown 8vo. 6s. net.

This is essentially a practical work, and botany is only incidentally touched upon. The timbers dealt with are those in most general use, either in their native districts or in the timber trade, together with some others which are likely before long to come into the market.

CYTOLOGY

THE ESSENTIALS OF CYTOLOGY: An Introduction to the Study of Living Matter. By Charles Edward Walker, Assistant Director of the Cancer Research, Liverpool, and Honorary Lecturer in Cytology to the School of Tropical Medicine in the University of Liverpool; formerly Demonstrator of Zoology in the Royal College of Science, London. Illustrated. Demy 8vo. 7s. 6d. net.