A Wy.EKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To the solid ^^outid 

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



IKTlDXJCTIOWr COIXoiS. 



APP3' PATENTED INDUCTION COILS are now manufactured 



concurrently by 



NEWTON & CO., 3 l-I-KET STREET, LONDON. 



"X" RAY "FOCUS" TUBES, 30s. 



SPECIAL TUBES FOR FLUORESCENT SCREENS. 



Complete Apparatus for Rontgen "X" Rays, with 



Coils and Fluorescent Screens, &c. 



Detailed List on Application. 



No Scientific Man 



sliould 



be without a 



FRENA 



CAMERA. 



full particulars 



free 

 on application. 



R.&J.BECK,Ltd, 68 Cornhill, London, E.C. 



BROWNING'S "STRAND" 



HALF-PLATE 



PHOTOGRAPHIC OUTFIT. 



Comprising i-PIate Double Ex- 

 tension Mahogany body Camera, 

 with Ri.sing and Falling Front, 

 Reversing Back and Leather Bel- 

 lows ; one Double Dark Slide ; 

 Rapid Rectilinear Lens, Iris Dia- 

 phragm ; Thornton-Pickard Shutter;. 

 Tripod Stand ; Focussing Cloth, 

 and Waterproof Case. 



Price complete, £4 18s. 6cl. 



Illustrated Catalogue of Photo- 

 graphic Apparatus Post Free. 



JOHN BRO\SrNING, 



Manufacturing Optician, 

 63 STRAND, LONDON, W.C. 



NEGRETTr & ZAMBRA, 



SOLE MAKERS OF 



JORDAN'S (PATENT) SUNSHINE RECORDER. 



New Simplified Model, 

 adjustable for any 

 latitude, and tho- 

 roughly efficient. 

 Price £1 7s. 6d. 



Sensitised Charts, 

 5s. per 100. 



NEGRETTI 

 ZAMBRA, 



Scientific Instrument 

 Makers to the Queen, 



38 HOLBORN VIADUCT. 



=: Branches — 45 Cornhtll, 

 ~ 122 Regent Street, 

 London. 



ILLUSTRATED DESCRIPTION POST FREE. 



Telephone No. 6583. Telegraphic Address, " Negretti, London." 



