9 



6"<^6V/^ 



A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



' ' To the solid ground 

 0/ Nature trusts the mind which builds Jor aye." — WoRUSWOKiii. 



No. 1675, Vol. 6s] 



THURSDAY, DECEMeER 5, 1901. 



Pricb. Sixpence. 



Registered as a Newspaper at the General Post Office.) 



[All Rights are Reserved. 



ELECTRIC LANTERN. 



NEW PATTERN CHEAP ELECTRIC LANTERN, 

 fitted witli Hand-feed Arc Lamp in Case, £10 10s. 



New Season's List of Lanterns and Slides post free. 



3V e: -w T o »r «sc oo., 



OPTICIANS, &e.. TO THE KING, 

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X-RAY TUBES. 



Special arrangement 

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for use wilh 



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Send for our 

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JOHN J. GRIFFIN & SONS, Ltd., 



20-26 SARDINIA STREET, LINCOLN'S INN FIELDS, 

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THE NEW BOOK. 



"PRACTICAL NOTES ON TELEPHOTOGRAPHY. 



50 PAGES, 



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Special "' Illustrated Price List of Instruments, suitable foi' 

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 38 HOLBORN VIADUCT, E.C. 



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 AWARDED TWO GOLD MEDALS PARIS EXHIBITION 1900. 



