"The author is widely known and highly respected as an authority on the chemistry of oils and the technics of lubrication, and it is safe to say that no work of similar interest or equal value to the general oil-selling and consuming public has heretofore appeared in the English language."--_Drugs, Oils and Paints,_ U.S.A. "This valuable and useful work, which is both scientific and practical, has been written with a view of supplying those who deal in and use oils, etc., for the purpose of lubrication, with some information respecting the special properties of the various products which cause these various oils to be of value as lubricants."--_Industries and Iron._ "A mere glance at the table of contents is sufficient to show how various are the conditions to which these materials have to be applied, how much knowledge is required for the selection of the right kind for each particular purpose, and how by processes of mixture or manufacture the requisite qualities are obtained in each case."--_Manchester Guardian._ * * * * * =AMMONIA AND ITS COMPOUNDS:= Their Manufacture and Uses. By CAMILLE VINCENT, Professor at the Central School of Arts and Manufactures, Paris. Translated from the French by M. J. SALTER. Royal 8vo. 113 pp. 1901. Thirty-two Illustrations. Price 5s.; India and Colonies, 5s. 6d.; Other Countries, 6s.; strictly net. =Contents.= Chapters I., =General Considerations=: Sections 1. Various Sources of Ammoniacal Products; 2. Human Urine as a Source of Ammonia. II., =Extraction of Ammoniacal Products from Sewage=: Sections 1. Preliminary Treatment of Excreta in the Settling Tanks--The Lencauchez Process, The Bilange Process, The Kuentz Process; 2. Treatment of the Clarified Liquors for the Manufacture of Ammonium Sulphate--The Figuera Process and Apparatus, Apparatus of Margueritte and Sourdeval, The Lair Apparatus, Apparatus of Sintier and Muhe, Apparatus of Bilange, The Kuentz Process, Process and Apparatus of Hennebutte and De Vaureal; 3. Treatment of Entire Sewage--Chevalet's Apparatus, Paul Mallet's Apparatus, Lencauchez's Apparatus. III., =Extraction of Ammonia from Gas Liquor=: Sections 1. Clarification of Gas Liquor; 2. Manufacture of Ammonium Sulphate--A. Mallet's Apparatus, A. Mallet's Modified Apparatus, Paul Mallet's Apparatus, Chevalet's Apparatus, Grueneberg's Apparatus; 3. Concentration of Gas Liquor--Solvay's Apparatus, Kuentz's Apparatus, Grueneberg's Apparatus. IV., Manufacture of Ammoniacal Compounds from Bones, Nitrogenous Waste, Beetroot Wash and Peat=: Sections 1. Ammonia from Bones: 2. Ammonia from Nitrogenous Waste Materials; 3. Ammonia from Beetroot Wash (Vinasse): 4. Ammonia from Peat--Treatment of the Ammoniacal Liquors. V., =Manufacture of Caustic Ammonia, and Ammonium Chloride, Phosphate and Carbonate=: Sections 1. Manufacture of Caustic Ammonia; 2. Manufacture of Ammonium