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GAYTON A. DOUGLASS & CO. 



Merchants in all supplies pertaining to 

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^he Travelers Insurance Company 



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WM. S. KIMBALL & CO. 



SAMUEL HENSON, 



Mineralogist and Geologist, 



invites visitors to London to inspect his choice speci- 

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Catalogue on application. 

 SAMUEL HENSON, 277 Strand, London, 



OPPOSITE NORFOLK STREET. 



QUSTAV E. STECHERT, 



76G Broadway, New York. 



Importer of Scientific Books and Periodicals. 

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ft WESTERMANN & CO., 



(Established 1848,) 



838 Broadway . . . NEW YORK, 



FOREIGN BOOKSELLERS AND IMPORTERS. 



SCIENCE. 



AN ILLUSTRATED WEEKLY JOURNAL. THE SCIENCE 

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HORSFORUS 



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GERMAN SIMPLIFIED. 



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MAGAZINES AND REVIEWS! I 



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



