A WEEKLY ILI^CTftATEDToURNAL OF SCIENC^ 



" Tn the solid ground 

 ,,/ Nniuro trusts the -nnd which builds for aye. "— Wordsworth. 



No. 2280, Vol. 91J 



THURSDAY, JULY 10, 1913 



[Price Sixpence 



[All Rights Reserved. 



New Catalogue of Optical and 

 Laboratory 



ARC LAMPS, RESISTANCES, &c. 



Just Published. Post Free. 



New Catalogue of 



INEXPENSIVE SCIENCE 



LANTERNS, &c. 



(Ready in a few days.) 



NEWTON <3 CO., 



Optical Lantern Specialists 

 by Royal Warrant to H.M. the King, 



72 WIGMORE STREET, LONDON, W. 



Established over 200 Years. 

 Largest Demonstration Rooms in London. 



REYNOLDS & BRANSON, Ltd. 



Awards-Grand Prix. Turin. 

 Cold Medals, Allahabad, London, and Turin. 



emonstrate the short life of the Emanation from Thorium 

 use with the lantern. Comolete with Thorium Hydrate. 



£1 . 1 . O 



/Veto Descriplioe Circular of Accessory Apparatus for the 



"S. & R" lantern, post free. 



14 COMMERCIAL STREET, LEEDS. 



The Handle 

 London Model 



This is a new model, in which 



the limb is made so as to form 



a convenient handle for lifting 



the microscope. Otherwise it 



is similar to the ordinary 



London model. 



No. 1325. Stand, in case, 

 £3 5 6 



No. 1329. Stand, in case, 

 with spiral focussing 

 substage ...4 



N0.364A. Eye- 

 piece 5 O 



No. 801. iirds 

 Object Glass 12 O 



No. 803. itn 

 Object Glass 1 10 O 



Full Particulars of 



R. & J. BECK, 

 68 Cornhill, E.C 



STANDARD 

 ANEROID 

 BAROMETER 



brass case, 4'/ dial 

 divided to '01 inch 

 (or to 1 m/m), 

 with index hand. 

 In morocco case. 

 Price £5.5.0. 

 N.P.L. certificate 

 8s. 6d. extra. 



NEGRETTI & Z AM BRA 



Scientific Instrument Makers. 

 Holborn Viaduct, London, E.C. 

 City Branch : 45 Cornhill, E.C. 

 West End : 122 Regent St., W. 



Price List of 

 " Barometers 

 sent free on 

 request. 



