1. Construction of coils; sizes of wire; winding; testing; insulation; general remarks; medical and spark coils. 2. Contact breakers. 3. Insulation and cements. 4. Construction of condensers. 5. Experiments. 6. Spectrum analysis. 7. Currents in vacuo; air pumps. 8. Rotating effects. 9. Electric gas lighting; in multiple; in series. 10. Primary batteries for coils; varieties; open circuit cells; closed circuit cells; solutions. 11. Storage or secondary batteries; construction; setting up; charging. 12. Tesla and Hertz effects. 13. Roentgen Radiography. 14. Wireless telegraphy; arrangement of circuits of coil and coherer for sending and receiving messages; coherers; translating devices; air conductors; tables; contents; index. XII + 270 Pages, 79 Illustrations, 5 ◊ 6-1/2 Inches. Cloth. $1.00. * * * * * PRINCIPLES OF ELECTRICAL POWER. (CONTINUOUS CURRENT.) FOR MECHANICAL ENGINEERS. BY A. H. BATE, A.M.I.E.E. The rapid progress that has been made of late years in the application of electricity to industrial purposes, and particularly in the transmission of power by means of the electric motor, has made it imperative for every engineer who wishes to keep up to date to have some knowledge of the way electrical currents are controlled and used for practical purposes. This work is especially written for the practical engineer, mathematics being avoided. Contents of Chapters. 1. The Electric Motor. 2. Magnetic Principles. 3. Electrical Measurements. 4. The Dynamo. 5. Construction of Motor. 6. Governing of Motors. 7. Open and Closed Motors; rating. 8. Motor Starting Switches. 9. Speed Control of Shunt-wound Motors. 10. Series Motor Control. 11. Distribution System. 12. Installing and Connections. 13. Care of Dynamos and Motors. 14. Cost of Plant. 15. Examples of Electric Driving. Horse-power absorbed by various machines, including general engineering and shipyard machines; wood working and printing machinery (arranged in 14 pages of tables). XII + 204 pages, 63 illustrations, 12 mo. cloth. $2.00. * * * * * THE PRACTICAL ENGINEER'S HANDBOOK. TO THE CARE AND MANAGEMENT OF ELECTRIC POWER PLANTS By NORMAN H. SCHNEIDER, _Chief Engineer, "White City," Colingwood, Ohio_. EXTRACTS FROM PREFACE.