INCANDESCENT LIGHTING 



ON 



ARC LIGHT CIRCUITS 



THE BROWN AUTOMATIC CONVERTER 



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

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Can be used with any make arc dynamo. 



Any number of lamps can be turned on or off without 

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Invaluable to lighting companies as a means by which 

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Addi 



THE BROWN ELECTRIC COMPANY, 



400 Wood Street, Pittsburgh, Pa. 



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FOR SALE. 



A GEOLOGICAL MAP OF THE STATE OF NEW- 

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Please address L. W. O- .office Science, ^-j Lafayette Place, 

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I 



"THE ELECTRICAL REVIEW," 



Anillustruted weekly journal, is theacknowledgcd lead- 

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SCIENCE. 



AN ILLUSTRATED WEEKLY JOURNAL. THE SCIENCE 

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

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Address all correspondence about contents of paper to 

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Subscriptions. — In United States and Canada, $5 a year. 



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HORSFORD'S 



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Rumford Chemical Works, Providence, R. I. 



SUMMER COURSE I2T BOTANY. 



At the Botanic Garden of Harvard University. 

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Entered at the Post-office in New York as second-class mail matter. Copyright, 1886, by The Science Company. 



