A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To the solid ground 

 i)f Mature trusts the mind which builds for aye." — Wordsworth. 



No. 2571, Vol. 102] 



THURSDAY, FEBRUARY 6, 1919 



[Price Ninepence. 



1 as a Newspaper at th 'est Office.) 



[All Rights Reserved 



BALANCES & WEIGHTS 



Graphite-Selenium Cells 



FOURNIER D'ALBE'S PATTERN. 



Great Stability and High Efficiency. 



With a sensitive Se surface of 5 sq. cm. and a voltage 20 the 

 additional current obtainable at various illuminations (in 

 metre-candles) is : — 



For particulars and prices apply to the S01.E Agents : 



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THE SILICA SYNDICATE, Ltd., \< fy 



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BECKMANN THERMOMETERS 



With 6 degrees Centigrade divided 

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