A WKKKLV ILLUSTRATED JOURNAL OF SCIENCE. 



' ' To the solid ground 

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



No. 1 399, Vol. 54] 



THURSDAY, AUGUST 20, 1896. 



[Price Sixpence. 



Registered 



, Newspaper at the General Post Office.) 



(All Rights are Reserved. 



THE BEATING OF THE HEART 

 HE MOVEMENTS OF THE DIAPHRAGM 



an Ije seen l>y the aid of the Special " Focus " Tubes (z^s. 



ich) anil the Fluorescent Screens (35/. each) made by 



EWTON & CO., 3 Fleet Street, Lo.ndon, if used with 



one of their 6-inch Induction Coils. 



NALDER BROS. & CO., 



LONDON. 



NEWTON & CO., 3 FLEET STREET, LONDON, 



re now prepared to supply the well-known " Focus " Tubes 



manufactured by them at the reduced price of 25s. each. 

 These Tubes are still unsurpassed for Rapidity, Brilliancy, 

 id Definition. 



When ordering, the length of Spark to be used, should be 



entioned. 



\\\ the Tubes for 6" Spark and upwards will work right 



rough the human body, showing (he heart, liver, spine, ribs, 



ovements of the heart, diaphragm, &c. 



Customers can see these Tubes at work at 3 Fleet Street 



TNIION. ' 



EW FLUORESCENT SCREENS, extremely brilliant, 

 8 ■ 5", 35s. each : 10 8', 63s. each. 



3 -&\ 



N. C. S. 



I'xioivEsoivr 



REFLECTING 

 GALVANOMETER. 



5000 OHMS RESISTANCE. 



VERY SENSITIVE. 



PRICE 



Write for CATALOGUES. 



Cable Address : 



SECOHM, LONDON. 



IVo Aseuin in i:.S.A. 



This instrument delivered Free anywhere in U.S.A. 

 for *60 C.O.D. 



OHN J. GRIFFIN & SONS, 12 



22 GARRICK STREET, LONDON, W.C. 

 :-RAY TUBES, " FOCUS " PATTERN. 



For Photographic Work .niy. 15s. e.ich. 



For Photographic and Screen Work, 25s. each. 



For Photographic and Screen Work, exhausted for 



use Willi CniU giving 6-inch .Spark and upwards, 35s. each. 



A and K arc exhausted for use with 3. inch and 4-inch Spark 



Coils. 

 «K. A. A. C. SWINTON, April i8, 1896.-" The Speci.il Vacuum Tube 

 J recently supplied to me has been tested in my laboratory with very 

 isfactory results." ' ^ 1 



'rof. CHATTOCK, University College, Bristol —"The tube you sent 

 wa> an excellent one— we have not had a belter. Plea.se send another as 

 *l a--i you .-ire able." 



INDUCTION COILS. 



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



Our own Manufacture, as supplied to "The Lancet," 



Shelford Bidwell, Esq., M.A., F.R.S., and others. 



rlR ARNOLD H. Ul.l.YKTT. F.K.( ;.S.. &c.—" The Coil gives exceed- 

 K- gooil rcMilt, -uKl with its use I l,.-,ve taken .some splemlid, well-defined 

 dow photogr;tpns. I 



PI-.XTOIlESCEKrT SCIiEEZg-S 



cellent definition, any .Size made to Order. .Sizes in Muck : 



STTlVCIVt ER, UOH .IP.A.'yS. 



NEGRETTI & ZAMBRA'S 



BINOCULARS AND TELESCOPES. 



d with Brown 

 £2 IDs. 

 Perfect Definition & High Power. 



£2 2s. 



£2 2s. 



hes. 



As supplied by NEGRETTI & ZAMBRA to the War Office. 



Length, when closed, ii inches. Combining; hi^h power .ind portability. 



NEGRETTI & ZAMBRA, 



SCIENTIFIC INSTRUMENT MAKERS to the QUEEN 



38 HOLBORN VIADUCT, E.C. 



Branches : 45 CORNHILL; 122 REGENT STREET. 



Illustkateu Pkice Lisis Fkee by Post. 



