SCIENC 



Friday, June 8, 1900. 



Single Copies, 15 cts. 

 Annual Subscription, 85.00. 



QUEEN INSTRUMENTS 



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Queen Projection Galvanometer 



An Instrument designed for Lecture Table and Lantern Work. Scale frame fits the ordinaryjpro- 

 jection Lantern and deflections can be sliown on screen. 



The Galvanometer is of the D'Arsonval type, sufficiently sensitive to show Induction and Thermo 



eifeots. The current produced by one volt through 500,000 ohms will produce a deflection of one scale division. 

 Resistance about 600 ohms. With key (not shown in cut) mounted on Galvanometer the motion is dead-beat. 



PHOTOMETERS-INDUCTION COILS-PHYSICAL APPARATUS 

 Apparatus Imported from any Foreign Maker 



59 Fifth Avenue, New York 

 480 Monon Bldg., Chicago 



QUEEN & CO., Inc. 



J. G. GRAY, President 



ELECTRICAL AND SCIENTIFIC INSTRUMENTS 



1010 Chestnut St., Philadelphia 



