A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



* To the solid ground 

 'lire trusts the mind which builds for aye/ — Wordsworth. 



No. 2559, Vol. 102I THURSDAY, NOVEMBER 14. 1918 



1 Pru e Ninepeni 1 . 



Registeri eneral l'osl office] 



(All Rights Reserved 



BALANCES & WEIGHTS 



REYNOLDS &, BRANSON, Ltd. 



manufacturers of Laboratory Fittings and Furniture, 



Chemical Apparatus and Chemicals. 



"RYSTOS" CHEMICAL BENCH, as supplied to the National Physical 



Laboratory, Teddington, and important Chemical and Munition Works 



throughout the country. 



Graphite-Selenium Cells 



FOURNIER (yALBE'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 : — 



At 1 m.c. 

 At 50 „ 

 At 500 „ 



1 miliiamp. 

 1 



2 



For particulars and prices apply to the Soi.k Agents : 



John J. Griffin & Sons, 



Makers of Physical and Electrical Apparatus, 



Kemble Street, KINGSWAY, 

 LONDON, W.C. 2 



CHEMICAL, PHYSICAL, and TECHNICAL LABORATORIES 



fully equipped with Benches, Fume Chambers, etc. 



Designs and quotations submitted on application. 



14 COMMERCIAL. STREKT, LEEDS. 



CLINICAL THERMOMETERS 



Tested under the Govern- 

 ment Order of Oct. 11, 1918, 

 and bearing the mark of the 

 National Physical Laboratory 



NEGRETTI & ZAMBRA 



38 HOLBORN VIADUCT, E.C. 1 

 5 LEADENHALL ST., E.C. 3 

 122 REGENT STREET, W. 1 



LONDON. 



