NA TURE 



[October 5, 1905 



Ultra- Violet Rays 



THE 

 NEW 



MERCURY 



VAPOUR 



LAMP 



MADE OF 



UVIOL GLASS 



For Physical and 

 Medical Purposes. 



Current 



consumption only 2 



to 3 amperes. 



ISENTHAL & CO., 



85 MORTIMER STREET, LONDON, W. 



CATALOGUE of 

 PHYSICAL APPARATUS. 



NINTH EDITION. 



Over SOO pnijeH. profiisclii illiislratftl, of all 

 the latest niifi most modern ap/Kirottis for 

 feaehinri , . 



Heat, Light, Sound, 



Frictional and Voltaic Electricity, 



Pneumatics, Hydrostatics, Mechanics, 



Mensuration, Hygiene, &c. 



EVERY INSTRUMENT CHEAPLY, EFFICIENTLY, AND 

 ACCURATELY MADE. 



CATALOGUES SENT FREE, on api)li cation, to 

 Schools, Colleges, and Institutions. 



TOWNSON & MERCER, 

 34 CAMOMILE ST., E.C. 



EXPERIMENTAL GLASS BLOWING 

 FOR RESEARCH WORK 



Correctly and promptly carried out for Laboratories and Scientific Men from Rough Sketch, 



as executed by us for many years for London University, Victoria University, Manchester, 



and the principal Institutes throughout the Kingdom. 



LISTS : —Chemical Apparatus — Chemicals — Balances — Assaij — Thermometers — Electrical 



Apparatus— ^Fociis Tubes, X-Ba;/, and Wireless Teleffrap/ii/ Apparatus— or SPECIAL 



VIIOLESALE (for Quantifies)— free on application. 



C. E. MULLER, ORME & CO., Ltd., HSTflGH HOLBORN, LONDON. 



THE SlVCAX^r^ESX 

 I*RACTICAI-. CAIVIERA IVIADE. 



The Stereoscopic Company's 



NEW BLOCKNOTES CAMERA 



is no larger than an ordinary purse ami yet produces perfect photographs 

 under any conditions. 



Write for Illustrated "Booklet (N) of this charming little 

 Camera free from 



THE LONDON STEREOSCOPIC CO., 



106 & 108 Regrent St., W., or 54 Cheapside, E.C. 



iinted by Richard Clav and Sons, Limited, at 7 & 8 Bread Street Hill, Queen Victoria Street, in the City of London, and published by M 

 ANDCo.,LiMiTED,atS-.. Martin'sStreet, London, W.C, and The Macmillak Company, 66 Fifth Avenue, New Yorl;.— Thursday, October 



