With 370 Diagrams and Engravings. 8vo., cloth, 328 pp Net, $3.50

Third Edition. With 140 full-page Plates, 65 Tables, and 165 pages of descriptive letter-press. 4vo., cloth, 300 pp. $7.50

PATCHELL W. H. Application of Electric Power to Mines and heavy Industries.

91 illustrations 6 1/2 x 9 1/4, cloth, 203 pp Net, 4.00

139 illustrations, 5 1/4 x 7 1/4. cloth, 203 pp Net, $2.00

PERRINE, F. A. C. Conductors for Electrical Distribution: Their Manufacture and Materials the Calculation of Circuits, Pole Line Construction, Underground Working, and other Uses.

Second Edition. Illustrated. 8vo., cloth, 287 pp Net, $3.50

A Handbook for Electricians and Operators. Seventeenth Edition. Illustrated. 8vo., cloth, 234 pp $1.50