SCIENCE.— AD VERTISEMENTS. 



SOME OF THE PUBLICATIONS 



OF 



The W. J. Johnston Company 



The Electrical World. 



An Illustrated Weekly Review of Current Progress in 

 Electricity and its Practical Applications. Annual sub- 

 scription. $3.00 



Dictionary of Electrical Words, Terms 

 and Phrases. 



By Edwin J. Houston, Ph.D. Fourth edition. Greatly 

 enlarged. 10,0-12 words and terms defined ; 12,073 defini- 

 tions ; 990 double column octavo pages; 582 illustrations, 

 an indispensable reference book, not only for electri- 

 cians, but for everyone interested in current progress. 



$7.00 



Shop and Road Testing of Dynamos and 

 Motors. 



By Eugene C. Parham and John Shedd. Practical and 

 thorough. 526 pages. $2.00 



Electro'Dynamic Machinery. 



By E. J. Houston, Ph.D., and A. E. Kenuelly, D.Sc. A 

 text-book on continuous-current dynamo-electric ma- 

 chinery for electric-engineering students of all grades. 

 331 pages, 232 illustrations. $2,60 



Practical Calculation of Dynamo=Elec= 

 trie Machines. 



A Manual for Electrical and Mechanical Engineers, and 

 a Text-book for Students of Electrotechnics. By A. E. 

 Wiener. 683 pages, 375 illustrations. $2.50 



Gerard's Electricity. 



With chapters by Dr. Louis Duncan, C. P. Steinmetz, A. 

 E. Kennelly and Dr. Gary T. Hutchinson. Translated 

 under the direction of Dr. Louis Duncan. .392 pages, 112 

 illustrations. As a beautifully clear treatise for students 

 on the theory of electricity and magnetism as well as a 

 r^sumiS for engineers of electrical theories that have a 

 practical bearing, the work of Professor Gerard has been 

 without a rival in any language. $2.50 



Electrical Power Transmission. 



By Dr. Louis Bell, Ph.D. Uniform with Crosby cfe Bell's 

 " Electric Railway." Essentially practical in its charac- 

 ter. Cloth. $2.50 



The Theory and Calculation of Hlter= 

 nating Current Phenomena. 



By Chas. Proteus Steinmetz. Contains the very latest 

 knowledge relating to alternate current phenomena, 

 much of which is original with the author, and here ap- 

 pears for the first time in book form. $2.50 



Electric Lighting Specifications. 



For the use of Engineers aud Architects. Third edition 

 entirely re-written. By E. A. Merrill. 231 pages. $1.50 



Electricity One Hundred Years Hgo and 

 To=day. 



By Edwin J. Houston, Ph.D. 190 pages, illustrated. $1.00 



Alternating Electric Currents. 



By E. J. Houston, Ph.D., and A. E. Ivennelly, D.Sc. 

 (Electro-Technical Series.) $1-00 



Electric Heating. 



By E. J. Houston, Ph.D., and A. E. ICennelly, D.Sc. 

 (Electro-Technical Series.) $1.00 



Magnetism. 



By E. J, Hoaston, Ph.D., and A. 'E. Kennelly, D.Sc. 

 (Electro-Technical Series.) $1.00 



Electro=Therapeutics. 



By E. J. Houston, Ph.D., and A. E. Kennelly, D.Sc 

 New Edition. Enlarged by addition of chapter on X- 

 Eays (Electro-Technical Series,. $1.00 



Electric Hrc Lighting. 



By E. J. Houston, Ph.D., and A. E. Kennelly, D.Sc. 

 (Electro-Technical Series.) $1.00 



Electric Incandescent Lighting. 



By E. J. Houston, Ph.D., and A. 



(Electro-Technical Series.) 



The Electric Motor. 



By E. .1. Houston, Ph.D., and 

 (Electro-Technical Series.) 



A. E. Kennelly, D.Sc. 



Electric Street Railways. 



By E. J. Houston, Ph.D., and A. 

 (Electro-Technical Series.) 



The Electric Telephone. 



Kennelly, D.Sc. 

 $1.00 



By E. J. Houston, Ph.D., and A. E. Kennelly, D.Sc. 



(Electro-Technical Series.) 



$1.00 



Electric Telegraphy. 



By E. .J. Hou.ston, Ph.D., and 

 (Electro-Techuical Series.) 



Alternating Electric Currents. 



Their Generation, Measurement, Distribution and Ap- 

 plication. Authorized American edition. By Gisbert 

 ivapp. 166 pages. 37 illustrations, 2 plates. $1.00 



Electric Railway Motors. 



By Nelson W. Perry. 258 pages. Many illustrations. 



$1.00 



Original Papers on Dynamo Machinery 

 and Allied Subjects. 



Experiments with Alternating Currents 

 of High Potential and High Frequency. 



By Nikola Tesla. llii pages. 35 illustrations. $1.00 



Lectures on the Electro-Magnet. 



Authorized American edition. By Professor Sylvanus 

 P. Thompson. 287 pages. 75 illustrations. $1.00 



Dynamo and Motor Building for Ama^ 

 teurs. 



Copies of any of the above books, or any otlier electrical book published, wiU be sent by mail, 

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THE W. J. JOHNSTON COMPANY, 9 Murray Street, New York 



