NOTICE TO KEADEES. 



THE PUBLICATION OFFICE OF 



SCIENCE 



WILL HEREAFTER BE AT 



47 ZL^IF^^rZETTIE PLACE 



All communications should be addressed to 



"SCIENCE," 47 LAFAYETTE PLACE, NEW YORK. 



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. 



THE BROWN AUTOMATIC CONVERTER 



will supply and take care of ten to twelve 16 c.p. incandes- 

 cent lamps at any point on an arc light circuit from an initial 

 current 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 

 affecting the rest. 



Invaluable to lighting companies as a means by which 

 they can secure customers, from one up, for incandescent 

 lighting anywhere on their circuit without involving (he large 

 expense for incandescent lighting plants, or the necessity of 

 getting a large number of subscribers to commerce with. 



Address 



THE BROWN ELECTRIC COMPANY, 



400 Wood Street, Pittsburgh, Pa. 



SCIENCE. 



AN ILLUSTRATED WEEKLY JOURNAL. THE SCIENCE 

 COMPANY, OWNERS AND PUBLISHERS. 



Officers and Directors. — D. C. Gilman, of Baltimore, President; 

 Simon Newcomb, of Washington, Vice-President; Gardiner G. Hub- 

 bard, of Washington : Alfx. Graham Bell, of Washington ; O. C. 

 Mafsh, of New Haven • J. W. Powell, of Washington ; W. P. Trow- 

 bridge, of New York ; S. H. Scudder, of Cambridge. 



SCIENCE appears every Friday. Volumes begin in July and January. 

 Communications will be welcomed from any quarter. Rejected manu- 

 scripts will be returned to the authors only when the requisite amount of 

 postage accompanies the manuscript. 

 Address all correspondence to << SCIENCE " 



47 Lafayette Place, New York. 



Subscriptions. - 



-In United States and Canada, $5 a year. 

 In Great Britain and Europe, $6 a year. 



The Treasurer of the Science Company will in all cases send 

 a receipt for money paid to the publisher. 



HORSFORDS 



* 



Acid Phosphate .4jQ> 



(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. 



bv The Science Company. 



