SCI ENCE. -ADVER TISEMENTS. 



JULIEN'S IMPROVED LAPIDARY LATHES 



For SLICING and POLISHING rocks, minerals, fossils, 

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GUSTAVOS D. JULIEN, 932 Bloomfield St.. HOBOKEN. N. J. 



Ninth Revised Edition. Published Jan. 190i. 



The Microscope and Microscopical Methods 



By SIMON HENRY GAGE, of Cornell University. 



Important changes have been made and the chapter on 

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 New figures of American microscopes and apparatus. 

 Postpaid $1.50 as for the 8th edition. 



COMSTOCK PUBLISHING CO., Ithaca, N. Y. 



MARINE BIOLOGICAL LABORATORY 



Supply Department — 1. Zoology— Preserved Material 



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 2. Botany— Preserved Material of Algae, Fungi, Liver- 

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 dress GEO M. GRAY, rnratnr AnorisHoil. Maps 



THE BRAIN OF THE SHEEP, by Burt G. 

 Wilder. Third edition, revised, 1903. Explicit Direc- 

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HENRY COWELL,McGraw Hall, Cornell University, 

 ITHACA. NEW YORK. 



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THE SCIENTIFIC SHOP, 

 322 Dearborn Street, Chicago. 



WM. GAERTNER & CO. 



Astronomical and 

 Physical Apparatus 

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Seventh 

 Edition 



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FOR SALE AT ANY BOOKSELLER'S 



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