'J U V 



A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To the solid ground 

 Of Mature trusts the mind which builds for aye.^^ — Wordsworth. 



No. 2239, Vol. 90] 



THURSDAY, SEPTEMBER 26, r9i2 



[Price Si x pence 



Registered as a Newspaper at the General Post Office.) 



{All Rights Reserved. 



LANTTE 

 POX^ARI 



Elbow Polariseope, for illustrating the various phe- 

 nomena of polarized light, with polarizing glass plates, 

 prism and lenses, mounted in brass, with rack adjustment 

 to focus tube, in case, complete, JB7 Is. 



3WE;\7VT01W SZ CO. 



72 WIGMORE ST., LONDON, 



THE RAINBOW CUP 



C. V. HOV> .S LATENT. 



MAGICAL 

 COLOUR 



ASTOUNDING 

 EFFECTS 



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. 



SOLK MAKERS: 



JOHN J. GRIFFIN & SONS, Ltd. 



Kemble St., KINGSWAY, LONDON, W.O. 



XCEJYN^OILiDS Ac ]BISAI«rSOI«^, ILitcl. 



RYSTOS" MICROSCOPE 

 PLATFORM 



For use with the Stroud & Rendell Science Lanterns. This platform 

 is adjustable, so that any ordinary microscope (the draw lube being 

 removed) can be used for projection work. The platform can be raised 

 or lowered in order that the optical centre of the microscope may 



coincide with that of the lantern £1 7 ft 



CataU^g-ut: of Optical Lantt-riis and descriptive circular of Accessory 

 Apparatus for Ihi S. &' R. Lanterns, post free. 



14 coiviiMiEfi cia.il. st'ecee:'!', i:.e:e:ds. 



o«o*o«oao*ooo«o«o«o*o*o«o«o*o«o*o«o«o*o«o*o*o*o*o«o 



)«o*o«o*o«o*o»o*o«o«o*o«o«o*o«o*c*o 



NEGRETTI & 



"Hyetograph" 

 is a Recording 

 Rain Gauge that 

 has given great 

 satisfaction by its 

 perfect reHabiHty. 



Illuslraled Price List of 

 Recording &other Rain 

 Gauges sent post free. 



38 Holborn Viaduct, 



London, E.C. 



45 Cornhill, E.C. 



122 Regent St., W 



ZAMBRA'Si 



