^ 



'y 



.V 



A WREKLY ILLUSTRATED JOURNAL OF SCIENCE. 



' ' To the solid ground 

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



No. 1405, Vol. 54] 



THURSDAY, OCTOBER i, 1896. 



[Price Sixpence. 



Registered as a Newspaper at llie (Jeneral Post Office.) 



(All Righu are Reserved. 



X-RAY FOCUS TUBES. 



tie " Focus" Tubes manufacturuil l>y 



NEWTON & CO., 



3 FLEET STREET, LONDON, 



e still unrivalled for brilliancy and detinition, and are used by 

 ■arly all the leading workers. 



Dr. J. .Macintyre, of Glasgow, in Nature, September lo, 

 ys that with these Tubes he has obtained "some of the best 

 lotographic results in the deeper structures of the body." 

 In consequence of the large nuiiilier of these Tubes which have 

 )w been sold, it has been possible to reduce the price to 25s. 

 ch. With these Tubes and a 6" Coil and Fluorescent Screen, 

 e beating of the heart and the mo\ements of the diaphragm 

 n be readily seen in an adult. 



Fluorescent Screens, intensely brilliant, 

 S" X 5", 35s. ; lo" X S", 63s. 



1ST OF COILS, TUBES, SCREENS, 5fc. POST FREE. 



OHN J. GRIFFIN & SONS, '^ 



22 GARRICK STREET, LONDON. W.C. 

 COMPLETE X-RAY APPARATUS. 



OCUS TUBES. INDUCTION COILS. BATTERIES, 



FLUORESCENT SCREENS. WIMSHURST 

 ACHINES. and all PHOTOGRAPHIC REQUISITES. 



OUR TUBES, all of wlii. Ii aru w.Jl levied and gu.iranleed before 

 ini; -supplied, .ire divided into three el.Xs>es depending upon the work 

 nuiredlo l.e d-.ne, si/. :— 

 . For Photographic Work -mly, lOS. each. 



. For Photographic and Screen Work, 25s. each. 

 . For Photographic ami Screen Work, exhausted for 



use with Coils giving 6-inch Spark and upwards, 35s. each. 

 .\ and P. arc for use with 3inch and 4-inch Spark Coils. 

 INDUCTION COILS, of excellent finish, well mounted in ihoroush 

 nONni-; insulation; our own .l/(iMi//a<:/i<r.-, as supplied lo Shelford 

 dwell. F.S.I., M.A., K.R.S.; r*,- Lancet ; Prof, Hurstall, M.A., and others. 



3-in., £9; 4-in., £12; 5-in., £15; 6in., £18. 



PIjUORBSCBNT SCREENS, of excellent definition and 

 illiancy. ne.itly mounted in good M).ih.igany frame with h.andle. 



zes— 5-in. x 5. in., 10,6 ; 7-in. x 5-in., 12/6 ; 8-in. x 6-in., 15;- 



ANY SIZK MAD!-; TO OKDEK. 



DARK BOXES, with Removable Screens, from 20s. each. 

 Demonstrations, and all particulars as to methods of working, are 

 ren, either verbally or by correspondence, to intending purchasers, free 



CHARGE. 

 'it of Tirstimottiats, &=c.,from I. catting ExJ>crimentcrs, on amplication. 



NALDE R BROS, & CO ., london 



D'ARSONVAL GALVANOMETER 



Delivered Free anywhere in U.S.A. for S32 C.O.D. 



Write for 

 CATALOGUES. 



D'ARSONVAL 

 GALVANOiVIETER 



(As illustrated). 

 VERY PORTABLE 



SENSITIVE 



STJIVaiVt ER. HOr .IPA.'VS. 



NEGRETTI & ZAMBRA'S 



BINOCULARS AND TELESCOPES. 



Makers of the "OFFICER OF THE W.\TCH " TELESCOPE, 

 on all the vessels of H.M. Navy. 



£2 2s 



£2 2s. 



As supplied by NEGRETTI & ZAMBRA to the War Office. 



Length when closed, 11 inches. Combining high power and portahility. 



NEGRETTI &. ZAMBRA, 



SCIENTIFIC INSTRUMENT MAKERS to the QUEEN, 



38 HOLBORN VIADUCT, E.C. 



Branches: 45 CORNHILL; 122 REGENT STREET. 



Illustrated Price Lists Free bv Post. 



