SCIENCE 



(Vol. XV. No. 362 



Sprague £lectric Railiiray and Motor Company. 



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SIIVIPLE IN CONSTRUCTION. 

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THE 



M h 



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98 MILK ST., BOSTON, MASS. 



This Company owns tbe Letters 

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 No. 186,787. 



Tlie Transmissioa of Speech by 

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has brought a lot of 

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manufactured solely by tbe 



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CHANCE FOR ALL 



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ind Baulng Po 



WALKER PRIZES IN NATURAL HISTORY. 



The Boston Society of Natural History offers a first 

 priz.; of from S^o to Sroo, and a second prize cf S50, for 

 the best memoir, in English, on one of the foUowing sub- 

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 For further particulars apply to 



J. WALTER FEWKES, Secretary. 



Boston. Mass., Dec. i8th, 1889. 



One Thousand Dollar Prize ! 



THE AMERICAN SECULAR UNION offer a prize 

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Philadelphia, Nov. 1889. 1707 Oxford St. 



Readers of Science 



Corresponding with or visiting Adve7-tisers 

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H. Wunderlich & Co., 



868 BROADWAY, 



NEW YORK, 



Invite special attention to their latest 

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Manufacturers and Importers ot 

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OLD BOOKS. Catalogue No. 6 Now Ready. Part 

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