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A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To the solid ground 

 Of Nature trusts the mind whick builds for aye." — Wordsworth. 



No. 1685, Vol. 65] 



THURSDAY, FEBRUARY 13, 1902. , [PRIGE Sixpence. 



Newspaper at the General Post Office.) 



NEW DOUBLE-POLE (NEWTONIAN) MOTOR 

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 3 FLEET STREET, LONDON. 



X-RAY tubes: 



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REGULATION OF THE 



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NEGRKTTI & ZAMBRA'S 



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Aneroid Baromet 

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with Altitude Scale, Conipa_ss with Luminous Dial for 

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