I was highly pleased with the copy of Sloane's Electrical Library, which arrived in good condition. It is one of the most valuable works I possess in my library. The use of the Roentgen Rays in my profession has stimulated my desire for electrical knowledge greatly, and I consider Sloane's "Electrical Dictionary" a first-class book of reference. I shall be pleased to recommend it to my colleagues in search of such a work. Yours truly, P.J. CLENDINNIN, M.D., Hon. Medical Electrician to the Melbourne Hospital. MUNN & CO., Publishers, New York. JUST PUBLISHED. Second Edition, Revised and much Enlarged. Gas, Gasoline and Oil Engines By GARDNER D. HISCOX, M.E. The only American Book on the Subject. This is a book designed for the general information of every one interested in this new and popular motive power, and its adaptation to the increasing demand for a cheap and easily managed motor requiring no licensed engineer. The book treats of the theory and practice of Gas, Gasoline and Oil Engines, as designed and manufactured in the United States. It also contains chapters on Horseless Vehicles, Electric Lighting, Marine Propulsion, etc. Second Edition. Illustrated by 270 engravings. Revised and enlarged. LARGE OCTAVO. 365 PAGES. PRICE $2.50. CONTENTS. Chapter I.—Introductory, Historical. Chapter II.—Theory of the Gas and Gasoline Engine. Chapter III.—Utilization of Heat and Efficiency in Gas Engines. Chapter IV.—Heat Efficiencies. Chapter V.—Retarded Combustion and Wall Cooling. Chapter VI.—Causes of Loss and Inefficiency in Explosive Motors. Chapter VII.—Economy of the Gas Engine for Electric Lighting. Chapter VIII.—The Material of Power in Explosive Engines, Gas, Petroleum Products and Acetylene Gas. Chapter IX.—Carbureters and Vapor Gas for Explosive Motors. Chapter X.—Cylinder Capacity of Gas and Gasoline Engines, Mufflers on Gas Engines. Chapter XI—Governors and Valve Gear. Chapter XII.—Igniters and Exploders, Hot, Tube and Electric. Chapter XIII.—Cylinder Lubrication. Chapter XIV—On the Management of Explosive Motors. Chapter XV.—The Measurement of Power by Prony Brakes, Dynamometers and Indicators, The Measurement of Speed, The Indicator and its Work, Vibrations of Buildings and Floors by the Running of Explosive Motors. Chapter XVI.—Explosive Engine Testing. Chapter XVII.—Various Types of Gas and Oil Engines, Marine and Vehicle Motors.—Chapter XVIII.—Various Types of Gas and Oil Engines. Marine and Vehicle Motors—Continued. Chapter XIX—United States Patents on Gas, Gasoline and Oil Engines and their Adjuncts—1875 to 1897 inclusive—List of the Manufacturers of Gas, Gasoline and Oil Engines in the United States, with their addresses. A Few Extracts of Notices from the Press. It is a very comprehensive and thoroughly up-to-date work.—American Machinist.