A WEEKLY ILLUSTRATED JOURNAL OF SCIENC 



' To the solid ground 

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



No. 2722, Vol. 108] THURSDAY, DECEMBER 29, 1921 [Price One Shi? 



Registered as a Newspaper at the General Post Office.] 



[All Rights Reserved. 



NEWTON'S IN" ««!■') 

 DEMONSTRATOR'S LANTERN 



For all classes of 

 Projection Work. 



Full pa' ticvlars sent on application. 



NEWTON & Co., 72 Wigmore St., London, W.I 



(Specialists in Optical Projection Apparatus). 



REYNOLDS & BRANSON, Ltd. 



Chemical and Scientilic InstraiEent Makers to His Majesty's 



Government <Home and Overseas Dominions , Laboratory Furnishers 



and Mannla:turing Chemists. 



SCIENTIFIC I.\.STRLMENT MANlFACTLRERS 

 and LABORATORY FURNISHERS. 



An Accurate Balance. 



Strongly made, with 



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and Planes. 



LOW COST. 



N/1684 

 StuJent-'s Balance. 



This and other types 



made at *^ur works, 



Walthamstow. 



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THE " RY8T08 " BALANCE CASE. 



2* o' X 15' V 18' high, glazed ends, tops, and fronts, doors to turn up, and 



slide under top, carried on brackets fixed to wall, or cupboards can 



be fitted under same. As specially designed for and suppUed to 



The Schools, Shrewsbury. 



CHEMICAL, PHYSICAL, and TECHNICAL LABORATORIES 

 Fully Equipped with BENCHES. FUME CHAMBERS, &c. 



Catalogue of Chemical and Physical Apparatus and Chemicals. 



Designs of Benches and Fittings to suit all requirements. 

 (New Catalogue post free.) 



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Particulars of Student, 

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 LONDON. 



