A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To the solid ground 

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



No. 2249, Vol. 90] 



THURSDAY, DECEMBER 5, 1912 



[Price Sixpence 



. Newspaper at the General Post Office.] 



(All Rights Reserved. 



John J. Griffin & Sons, I' 



KINGSWAY, LONDON, W.C. 



Scientific Tnstrument IHaKers. 



'^^^ CC. V. Bovss Patent.) ^^ ^k- 



V For Studying Liquid Films. ^^^ .^\ 



A 



Unique 



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Gorgeous 



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Colour=effects. 



Packing and Carriaee 

 in United Kingdom, 1/- 

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Price 25 - 



NEON 



KRYPTON 



XENON 



Vacuum tubes of the above gases, guaranteed 

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NEON . . 

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£1 1 O 

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JLDAIVI HILGER, Ltd. 



75a CAMDEN ROAD, LONDON, N.W. 



The "Folding Minim' 



a compact^ 



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Acceptable Presents? 



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