A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



' To the solid ground 

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



No. 2237, Vol. 90] ^^THljRSDAY,, SEPTEMBER 12, 1912 [Price Sixpence 



Registered as a Newspaper at the General Post OflSce.] 



[AH Right"; Reserved. 



NEWTON & CO.'S 

 'DEMONSTRATOR'S" LANTERN 



FOR ELECTRIC OR LIMELIGHT 



With Prism for Erecting. 



and forVertical Projection, 



Price £10 10s. 



72 WIGMORE ST., 

 LONDON, W. 



THE RAINBOW CUP 



C. V. BOYS'S PATENT, 



MAGICAL 

 COLOUR 



A NEW INSTRUMENT 



or studying the colours of thin films. Produces the most 

 beautiful colour forms and colour changes imaginable. 



Price 25s., including two bottles of special soap solution 

 and full instructions. 



SOLE MAKERS: 



JOHN J. GRIFFIN & SONS, Ltd. 



Kemble St., KINGSWAY, LONDON, W.C. 



REYNOLDS & BRANSON, Ltd. 



AWARDED GRAND PRIX. TURIN. 1911.) 



SPECIAL APPARATUS 

 for Consterdine & Andrews' 

 'PRACTICAL ARITHMETIC." 



Set "A, 



20 models, 



£15 

 " B," 75 models, 



£0 16 6 



{Descriptive List on 

 Application. ) 



Special Apparatus for Mackenzie and Forster's 



Theoretical & Practical Mechanics & Physics. 



Detailed Catalogue on Application. 



CATALOGUES POST FREE. 



Scientific Apparatus and Chemicals. Apparatus for 



Teaching Mechanics, Machine and Building Construction. 



Optical Lanterns. Photographic Apparatus. 



14 COWIMERCIAL STREET, LEEDS. 



NEGRETTI & 

 "Hyetograph" 



is a simple, re- 

 liable, & approved 

 Recording Rain 

 Gauge at a very 

 moderate price. 



Please -..'rite 

 for painphlcl. 



38 Holtorn Viaduct, 



London, £.C. 

 43 Cornhai, E.C. 

 122 Regent St., W. 



ZAMBRA'S 



