SCIENCE.— AD VERTISEMENTS. 



A MOST USEFUL AND UNIQUE PRESENT 



lO Timely Books on -^ 



lO DiKFERENT IMPORTANT 



Practical Applications 

 of Electricity 



A COMPLETE ELECTRICAL LIBRARY 



written for the general reader in plain and simple language, 

 devoid of technicalities, and known as the 



"Elementary Electro-Technical Series." 



MAGNETISM. 



294 pages ; 94 illustrations. 



ELECTRIC MOTOR. 



377 pages; 122 illustrations. 



ELECTRIC HEATING. 



290 pages ; 86 illustrations. 



ELECTRIC TELEPHONE. 



412 pages; 143 illustrations. 



ELECTRIC TELEGRAPHY. 



448 pages ; 163 illustrations. 



ELECTRIC ARC LIGHTING. 



383 pages ; 155 illustrations. 



Electric Street Railways. 



367 pages ; 158 illustrations. 



Electricity in Electro-Thera- 

 peutics. 452 pages ; 147 illustrations * 



Alternating Electric Currents. 



225 pages ; 77 illustrations. 



Electric Incandescent Lighting. 



449 pages; 146 illustrations" 



Prof. EDWIN J. HOUSTON, 



Joint inventor of the Thomson-Houston system of electric lighting, author of "Houston's Dictionary of 

 Electrical Words, Terms and Phrases, ' ' and other works, 



...and... 



Dr. ARTHUR E. KENNELLY, 



The well-known electrical engineer, for years principal assistant in Mr. Edison's laboratory, 

 author of "Practical Notes for Electrical Students," and other works. 



The lo books can be bad in the box for $io.oo the set, or separately at $i.oo each. 

 Nothing could be more appropriate for a Christmas or birthday present. 



The W. J. Johnston Company 



Office of The Electrical Wokld. 9 Murray Street, New York:. 



