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PHOTO -MICROGRAPHY. 



GAYTON A. DOUGLASS & CO. 



Merchants in all supplies pertaining to 

 Photography. 



Catalogues furnished on application. 

 Correspondence solicited. 



185 & 187 Wabash Ave., Chicago. 



INCANDESCENT LIGHTING 



ON 



ARC LIGHT CIRCUITS. 



rHE BROWN AUTOMATIC CONVERTER 



vill supply and take care of ten to twelve t6 c.p. incandes- 

 .ent lamps at any point cn an arc light circuit from an initial 

 :urrent equal to a 2,oco c. p. arc lamp of 9.5 ampere. 



Can be used with any make arc dynamo. 



Any number of lamps can be turned on or off without 

 •.fleeting the rest. 



Invaluable to lighting companies as a means by which 

 hey can secure customers, from one up, for incandescent 

 ighting anywhere on their circuit without involving ihe laige 

 ;xpense for incandescent lighting plants, or the necessity of 

 jetting a large number of subscribers to commerce with. 



Address 



THE BROWN ELECTRIC COMPANY, 



400 Wood Street, Pittsburgh, Pa. 



SCIENCE 



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HORSFORDS 



Acid Phosphate jjk 



(Liquid), 



For Dyspepsia, Mental and Physical Exhaustion, 

 Nervousness, Wakefulness, Diminished Vitality, 

 etc. 



Prepared according to the directions of Pro- 

 fessor E. N. Horsford of Cambridge, from the 

 phosphates of lime, magnesia, potash, and iron, 

 with phosphoric acid in such form as to be readily 

 assimilated by the system. 



Universally prescribed by physicians. 



It is not nauseous, but agreeable to the taste. 



No danger can attend its use. 



Its action will harmonize with such stimulants as 

 are necessary to take. 



It makes a delicious drink with water and sugar only. 



Prices reasonable. Pamphlet mailed free. 



Rumford Chemical Works, Providence, R. I. 



lass mail matter. Copyright, 1886, by The Science Company. 



