CONTENTS:--Preface. Electric Phenomena. Electric Vibrations. Electro-Magnetic Waves. Modified Hertz Waves used in Radio-Telegraphy. Apparatus used for Charging the Oscillator. The Electric Oscillator: Methods of Arrangement, Practical Details. The Receiver: Methods of Arrangement, The Detecting Apparatus, and other details. Measurements in Radio-Telegraphy. The Experimental Station at Elmers End: Lodge-Muirhead System. Radio-Telegraph Station at Nauen: Telefunken System. Station at Lyngby: Poulsen System. The Lodge-Muirhead System, the Marconi System, Telefunken System, and Poulsen System. Portable Stations. Radio-Telephony. Appendices: The Morse Alphabet. Electrical Units used in this Book. International Control of Radio-Telegraphy. Index. _Nature._--"A very interesting and valuable book." MATHEMATICS THE CALCULUS AND ITS APPLICATIONS. A PRACTICAL TREATISE FOR BEGINNERS, ESPECIALLY ENGINEERING STUDENTS. With over 400 Examples, many of them fully worked out. By ROBERT GORDON BLAINE, M.E., Assoc.M.Inst.C.E. Lecturer at the City Guilds' Technical College, Finsbury, London, E.C. Author of "Hydraulic Machinery," "Lessons in Practical Mechanics," "The Slide Rule," etc. Crown 8vo. 4_s._ 6_d._ net. The difficulties which beset the beginner are fully explained, and the principles of the differential and integral calculus, and differential equations, are clearly set forth in the simplest language; each rule being illustrated by practical examples. Applications of the calculus to problems in engineering and physics form a feature of the work, which concludes with an up-to-date chapter on Harmonic Analysis, of special interest to electrical engineers and students of electro-technics. ENGINEERING ENGINEERING WORKSHOPS, MACHINES AND PROCESSES. By F. ZUR NEDDEN. Translated by JOHN A. DAVENPORT. With an Introduction by SIR A. B. W. KENNEDY, LL.D., F.R.S., M.Inst.C.E., M.Inst.M.E. Plates. Demy 8vo. 6_s._ net. A handbook of workshop practice for the young engineer. It fills a gap in our books for the practical training of engineers. MACHINE DESIGN. By CHARLES H. BENJAMIN, Professor of Mechanical Engineering in the Case School of Applied Science. Numerous Diagrams and Tables. Demy 8vo. 8_s._ net. Prepared primarily as a text-book, but containing mainly what the writer has found necessary in his own practice as an engineer. As far as possible the formulas for the strength and stiffness of machine details have been fortified by the results of experiments or by the practical experience of manufacturers. THE INTERNAL COMBUSTION ENGINE: Being a Text-Book on Gas, Oil, and Petrol Engines, for the use of Students and Engineers. By H. E. WIMPERIS, M.A., Assoc.M. Inst.C.E., Assoc.M.Inst.E.E. Illustrated. Crown 8vo. 6_s._ net.