Its Modern Use and Measurement, chiefly in its application to Electric Lighting and Telegraphy, including: 1. Some Points in Electric Lighting, by Dr. John Hopkinson. 2. On the Treatment of Electricity for Commercial Purposes, by J. N. Shoolbred. 3. Electric-Light Arithmetic, by R. E. Day, M.E. Fourth Edition. Illustrated. 16mo., boards, 166 pp. (No. 71 Van Nostrand's Science Series.) 50 cents

Translated from the German of Paul Hogner. 59 illustrations. 5 1/2 x 8, cloth, 100 pp. Net, $2.50

Illustrated. 5 x 8 1/2 half leather, 418 pp Net, $4.50

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Translated by Ph. Laubach. 335 illustrations. 6 1/2 x 9, cloth, 412 pp Net, $4.00

Illustrated. 8 vo., cloth, 227 pp.

By Prominent Engineers. Edited by C. E. Drayer and F. H. Newell. 5 1/4 x 7 1/2, 226 pp. Paper 75 cents, cloth $1.00

Third Edition, revised. Illustrated. 8vo., cloth, 393 pp Net, $4.00

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FLEMING, J. A., Prof. The Alternate-Current Transformer in Theory and Practice.