•o'o ir. 



A WEEKLY ILLUSTRATED JOURNAL OF SCIENCl 



" To the solid ground 

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



_^ »ni3n instif^^ 

 FEB 4 1913 



No. 2256, Vol. 90] 



THURSDAY, JANUARY 23, 1913 



[Price Sixpence 



the General Post Office.) 



[All Rights Reserved. 



MINIATURE ARC LAMP. 



Will work from any ordinary house lighting circuit. 

 Complete with resistance and ^Q Q Q 



mechanical tray oUU u v 



(For alternating current 10/6 extra.) 



II ,itc tor S/>Ki.d Leaflit. 



I^E^inTTON^ &• CO. (late of 3 Fleet Street), 



OpiMam by Royal Warrant lo HM. Ihe King. 



■72 wiGiviOFtE: stre;e:t, -vw. 



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. Otherw 



is similar to the ordinary 



London model. 



No. 1325. Stand, In case, 

 £3 5 6 



No. 1329. Stand, incase, 

 with spiral focussing 

 substage . . 4 O O 



No. 364A. Eye- 

 piece 5 O 



No. 801. irds 

 Object Glass 12 O 



No. 803. ith 

 Object Glass 1 10 O 



Full Pakticulaks of 



R. & J. BECK, 

 68 Cornhill, E.C. 



REYNOLDS & BRANSON, Ltd., 



Chcmica.1 and Scientific Instrument Makers to 

 His Majesty's Government (Indian, Home & Colonial). 



*' Rystos " 

 Analytical Balance 



with Magnalium Beam. 



nt of rider 

 der scale from end to end of 

 nd plumb line. The bearings 

 are agate throughout ; the beam of 

 hard magnalium. Base of black 

 crystal. Mahogany case with counter- 

 poised doors and brass levelling 



1 



I.^HIJl'/.'U.I.'lUUTi; 



i 





To carry 2do grammes, sensitive to 

 i/5th milligramme, or i/ioth milli- 

 gramme with a less load ... £7 O O 



Ditto, Ditto, to carry loo grammes, 

 with straight beam, of cheaper 

 struction £S 



6 



Particulars of other Magnalium Balances oa application. 



Catalogues of Chemical and Physical Apparatus, Cheniieals for 



Technical purposes and Research, Laboratory Fittings and 



Furniture, &c., &c., post free on application. 



14 Commercia.! Street, ILieeds. 



NEGRETTI & ZAMBRA'S | 



RECORDING RAIN GAUGES. | 

 I The "Hyetograph" 



! has but 3^ moving 

 ; parts, viz., the float, 

 ! the pen arm, and 

 ; the clocK drum. It 

 i is, therefore, simple. 



' Price, complete, with 

 ' charts, pen, and ink 

 \ £6 15 



5 Illustrated Price List of 

 5 Rain Gauges, etc., sent 



post free on request. 



• 38 Holborn Viaduct, 

 S London, E.C. 



; 45 Cornhill, E.C. 



1 122 Regent St., W. 



