l0 % 



DEC 181918 



A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To the solid ground 

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



No. 2561, Vol. 102I THURSDAY, NOVEMBE R 28, 1918 



[Price Ninepence. 



RcKistrreH as a Newspaper at the General Pos t Office.] 



[All Rights Reserved, 



Hal 



BALANCES &WEIGHTS 



Graphite-Seieniom Cells 



FOURNIEft 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 Soi.F. AGENTS : 



John J. Griffin & Sons, 



Makers of Physical and Electrical Apparatus, 



Kemble Street, KINGSWAY, 

 LONDON, W.C. 2 



CHEMICALS 



Analytical, Technical and Research. 



RECD. TRADE MARK APPARATUS 



Balances 



BENCHE S 



Fume Chambers, etc., 

 for 



a snow crystal Chemical Laboratories 



Price Lists and Estimates on Application. 



REYNOLDS & BRANSON, LTD., 



Contractors to the War Office, Admiralty, and 

 Egyptian Government, &c. , 



14 COMMERCIAL STREET, LEEDS. 



ACCURATE 



AND 



RELIABLE 

 THERMOMETERS. 



Send a note of your requirements 



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will offer you the best types we 



have in stock. 



NEGRETTI &, ZAMBRA, 

 38 HOLBORN VIADUCT, E.C. 1 



5 LEAD l!c"3 LL ST ' LONDON. ■" RE w f? T ST- 



Sir Our City Branch is at 5 Leadenhall Street. E.C. 3 



