SCIENCE 



New Series. 



Vol. XII. No. 310. 



Friday, December 7, 1900. 



Single Copies, 15 cts. 

 Annual Sdbsceiption, 86.00 



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Astronomical and 

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SPECIALTIES 



Astro NOMfCAL Telescope 

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MiCHELSON INTERFEROME 



DIVIDING Engines, 



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General Laboratory Ap 



PARATUS 



Universal Laborat 

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ry 



JUST RMADY 



Allen's Commercial 

 Organic Analysis 



Volume III. Part 1 



Tannins, Dtes, Colokino Matters, and Writing Inks. 

 Third Edition, Revised, Rewritten, and Enlarged by 

 I. Merritt Matthews, Professor of Ciiemistry and 

 Dyeing at the Philadelphia Textile School ; Member 

 American Chemical Society. Octavo. 



Cloth, $4.50 net. 



P. BLAKISTON'S SON & CO., 



JUST RBADY 



Groves and Thorp 

 Chemical Technology 



Volume III 



Gas Lighting. Including the Manufacture, Analysis, 

 Measurement, Storage, Purifying, Enrichment, etc., 

 of Illuminating Gas. By Charles Hunt, Manager 

 of the Birmingham Gasworks (England), Illus- 

 trated. Octavo. 



Cloth, $3.50 ; Half Morocco, $4.50 net. 

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SCIENTIFIC ADORNMENTS: 



some and unusual an offering as can be made, 

 mens suitable for gifts, $2.00 to $20.00. 



For Holiday Presents, a fine Green River fossil 

 fish, its dark phosphatized skeleton outlining on 

 the gray shale matrix like an etching, is as hand- 

 It may be framed under glass or left unframed as a tile. Speci- 



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ELECTRICAL ENGINEERING and 

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