A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



' ' To the solid ground 

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



No. 1395, Vol. 54] 



THURSDAY, JULY 23, 1896. 



Registered 



[Price Sixpence. 



Newspaper at the General Post Offie.-. I 



(All Rights arc Reservetl. 



NALDER BROS. & CO., 



LONDON. 



NEWTON & CO 



Manufacture 

 ALL APPARATUS 



^ONTGEN XRAY WORK. 



APPS COILS (Xewton. n,-,k"l 



J 1" , ±:12 12s.: 6 in. £22 10s.; 



■ ■! . £36 15s. 



FOCUS TUBES. 25s. e „ 1, 



FLUORESCENT SCREENS 



8 • . 35s.; I" s 63s ' 



ROWLANDS STAND (.., K,v ) for 



Medical Use, £2 f2s. 6d. 



? FLEET STREEh 

 LONDON. 



PKICK LISTS IREE. ^_^ 



lOHN J. GRIFFFn &r^OIMS~l2 



22 GARRICK STREET, LONDON. W.C. 

 t-RAY TUBES, " FOCUS " PATTERN. 



I. For Photographic Work ..nly, I5s. each 



!. For Photographic and Screen Worlt, 25s each 

 . l-or Photographic and Screen Work, cNhausted for 



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

 ^Coils^ "" "'''*""^'^ '■"'■ "^-^ "i"^ 3-inch and 4.inch Spark 



"recti- "^^l^lol' ^"'. ■'• ■596.-".The Special Vactiun. Tube 

 ii"sfaclo"7re "„•;[;. • ' *"" •"■=" "=''"='' '" "^^ laboratory wi.h very 



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 on a, >">» are .able •■ "°' '""' "^ '^""- '^'""= «"<* """'h^r .is 



INDUCTION COILS. 



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

 ^;-^^^ll: ':J:1^^^ \-^!ifv ^-•' ^Y CoSe^cee^. 

 .^cllcn. d.l,nitu,n. .-,,,>■ .s,« made to Order. .Sizes in st„,-L- - c v . .CTu 



N. C. S. 

 THOlVtSOlV 



^REFLECTINGS 

 GALVANOMETEIR. 



5000 OHMS RESISTANCE. 



VERY SENSITIVE. 



PRICE 



^si& lO O 



15s. ; 7- 



y .Sl/e made to Order. .Sizes i.i stock : 5X5 inch'es 

 Sinches, ,Ss.: 8 <6 in;hes, irx. W. each. ' 



Write for CATALOGUES. 



Cable Address : 



SECOHM, LONDON, 



"^^ IVo Agents in I'.S.A. 



This instrument delivered Free anywhere in U S A 

 for .*60 C.O.D. 



NEGRETTI & 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 tnsttument 

 Mailers to the Queen, 



38 HOLBORN VIADUCT. 



Branches— 45 Cornhill.. 



122 Rtt.E.NT StKEET,. 

 I.f.NDON. 



ILLUSTRATED DESCRIPTION POST FREE. 



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