

A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To the solid ground 

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



THE "NEWTONIAN" 



UNIVERSAL SCIENCE LANTERN 



BROWNING'S PLATYSCOPIC LENS. 



With Larger Angles, Increased Field, and Improved Definition 



Complete for Slides, Microscopic Objects, and Spectra. 



Price £18. 



For Lecturers on Light, Colour, and Colour Photography, &c. 



Sole Makers: NEWTON & CO., 3 FLEET STREET, LONDON. 



NEW 



MICROSCOPE 



THE 



"BRITISH STUDENTS." 



Microscope Stand No. 55, as 

 figured, with Iris Diaphragm, 

 One Bye-piece ; Double Nose- 

 piece, Two Object-glasses, 2/3" 

 and 1/6". adjusted to be in 

 about focus, and the whole 

 packed In polished Mahogany 

 Case, 



£6:8:6 



R. Sc J. SECK, Ltd., 



68 CORNHILL, LONDON, E.C. 



i: u - raved Real Si z.-. 



AN ACHROMATIC COMBINATION, 



COMBINING THE DEFINITION OF A MICROSCOPE WITH THE 

 PORTABILITY OF A POCKET LENS. 

 " If you carry a small Platyscopic Pocket Lens (which every observer of 

 Nature ought to do)."— Grant Allen in Knowledge. 



The Platyscopic Lens is invaluable to botanists, mineralogists, or ento- 

 mologists, as it focuses about three times as far from the object as the 

 Coddington Lenses. This allows opaque objects to be examined easily. 



The Platyscopic Lens is made of four degrees of power, magnifying 

 respectively lo, 15, 20, and 30 diams. ; the lowest power, having the largest 

 field, is the best adapted for general use. 



The Lenses are set in Ebonite Cells, and mounted in Tortoiseshell Frames. 



Price of the Platyscopic Lens, vtonnied in Tortoiseshell, magnifying either 



10, 15, 20, or yt diameter s , each power, 15s. 



In nickelised German Silver, each poiver^ 17s. 6d. 



Illustrated Description sent free. 



JOHN BROWNING, 63 STRAND. LOITDOIf. W.C- 



SPECTACLES 

 ELECTRIC LIGHT, INCANDESCENT GAS, 



And other Powerful Illuminants. 



apc 



NEGRETTI & ZAMBRA'S 

 THERMOSCOPIC LENSES 



Protect the Eyes from Glare, atul 

 RENDER THE LIGHT SOFT AND COOL. 



Illmlrated Price Lists of Optical and Meteorological Instruments 

 'ree by Post to all parts of the World. 



NEGRETTI and ZAMBRA, 

 SCIENTIFIC INSTRUMENT MAKERS to THE QUEEN, 



38 HOLBORN VIADUCT, E.G. 



BRANCHES: 45 CORNHILL ; 122 REGENT STREET. 



