ey is 
PeVIPEKEY Teeu Steak D JOURNAL OF “SGlIENGE. 
“To the solid ground 
Of Nature trusts the mind which builds for aye.”—WoRDSWORTH. 
No. 1426, VOL. 55] THURSDAY, FEBRUARY 25, 1897. [PRICE SIXPENCE. 
Registered as a Newspaper at the General Post Office.] [All Rights are Reseryed. 
INDUCTION COILS. BROWNING’S PLATYSCOPIC LENS. 
APPS’ PATENTED INDUCTION COILS are now manufactured With Larger Angles, Increased Field, and Improved Definition. 
concurrently by - 
NEWTON & CO., 3 FLEET STREET, LONDON. 
Engraved Real Size. 
AN ACHROMATIC COMBINATION, 
| COMBINING THE DEFINITION OF A MICROSCOPE WITH THE 
PORTABILITY OF A POCKET LENS. 
“Tf you carry a small Platyscopic Pocket Lens (which every observer of 
Nature ought to do).’ '—Gr NT 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 10, 15, 20, and 30 diams. ; the lowest power, having the largest 
field, is the best adapted for general use. 
*X” RAY “FOCUS” TU BES, 25s. | The Lenses are set in Ebonite Cells, and mounted in Tortoiseshell Frames- 
FLUORESCENT SCREENS, 63s. and cli | Price of the Platyscopic Lens, mounted tn Tortotseshell, magni- 
Complete Apparatus for Réntgen ‘‘ X”’ Rays, with Coils Sying either 10, 15, 20, or 30 diameters, 18s. 6d. each power. 
and Fluorescent Screens, &c. | Illustrated description sent free. 
LOE Detailed List on pplication. JOHN BROWNING, 63 STRAND, LONDON, W.C. 
ss NEGRETTI AND ZAMBRA’S 
The Frena (‘amera meg ee 
POSSSCOH HSS OOOOOOOD 
PARTICULARS of this 
unigue HAND-CAMERA | 
| 
e Baro is fitted in a 7 Matepaai Case with Glass Front, as shown 
The Thermograph is mounted in a japann 
may be had FREE on 
or either indoor or outdoor use, The abo’ 
application to 
arts, which only require changing once a wee er are iavaluable to 
| above 
BECK,‘ 
R. & J. gy | onc 
i lids and others w ho are unable to take daily readings of the ordinary 
Ltd., instruments. Price of each, with supply of Charts for one year, £6 10s. 
NEGRETTI & ZAMBRA, 
68 CORNHILL, SCIENTIFIC INSTRUMENT MAKERS TO THE QUEEN, 
38 HOLBORN VIADUCT, E.C. 
LONDON, E.C. ! Branches—45 CORNHILL, and 122 REGENT STREET. 
BeBoDAISH| UP-Jo-DATS 
