THE DISEASES OF ELECTRICAL MACHINERY. By Ernst Schulz. Edited with a preface by Sylvanus P. Thompson. Contents of Chapters: 1, Continuous Current Machines; breakdowns in the armature; brushes and brush holders; faults in the field winding; faults in the regulator or starter. 2, Singlephase and Polyphase Generators; faults in armature; grounds in generators; connections of different phases; field windings. 3, Singlephase and Polyphase Induction Motors; stator faults; rotor faults. 4, Transformers; faults in winding; effects of lightning. 5, Efficiency; examples of efficiency calculations.

94 pages, 42 illustrations, 12mo., cloth, $1.00.

ELECTRICAL TABLES AND MEMORANDA. A valuable little reference book for engineers, electricians, motor inspectors and others interested in the electrical science, containing many tables and much valuable information in a very small space, with a number of illustrations, by Prof. Silvanus Thompson. 64mo., roan, gilt edges, 40c.

THE VOLTAIC ACCUMULATOR. By Emile Reynier. Contents: Part 1, Principles, definitions, voltmeters. Part 2, Voltaic accumulators of various types. Part 3, Technology. Part 4, Application of accumulators. 202 pages, 62 illustrations, cloth, $3.00.

THE MERCURIAL AIR PUMP. By Prof. Silvanus P. Thompson, D. Sc. 37 pages, 43 illustrations, large 8vo., paper, 60c.[++]

THERMO-ELECTRIC REACTIONS AND CURRENTS, BETWEEN METALS IN FUSED SALTS. By Thomas Andrews, F.R.S. 18 pages, with illustrations and tables, 8vo., paper, 40c.[++]

THE APPLICATION OF ELECTRICITY TO RAILWAY WORKING. By William Edward Langdon. Contents of Chapters: 1, On the construction of a telegraph line. 2, Surveying. 3, Construction. 4, Telegraph instruments and batteries. 5, Block signalling. 6, Single line working. 7, Automatic block signalling. 8, Interlocking. 9, Miscellaneous appliances in connection with block signalling. 10, Train lighting. 11, Electric light and power. 12, Intercommunication in trains. 13, Administration. Appendix. Index. 301 pages, 6 full page plates and 143 engravings and diagrams, 8vo., cloth, $5.00.

ELECTRICAL TESTING OF TELEGRAPH CABLES. By Col. V. Hoskiaer. Third edition. 12mo., cloth, $1.50.

HARD SOLDERING, A MANUAL OF INSTRUCTION IN. By H. Rowell, with a chapter on soft soldering and brazing. 12mo., cloth, 75c.