Feb., 1907.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



SALE. 



Season's Stoc k. 

 Unique Opportunity 



8.000 LANTERN SLIDES. 



Plain - 6d. each. 

 Coloured 1/- each. 



BEST PHOTOGRAPHIC SLIDES, 



COMPRISING ALL SUBJECTS. 



Ghromatropes. Dissolving Sets. 



AT ONE THIRD ORIGINAL PRICE. 



OPTICAL LANTERNS. 



Russian Iron & Mahogany Bodies. 



SIX DOZEN LANTERN OBJECTIVES 



^VARIOUS FOCI) 



JETS, CONDENSERS, SLIDE CARRIERS, 



OIL LAMPS. LIMES, 

 GAS CYLINDERS, FITTINGS OF ALL KINDS, 



At one-third less than usual price. 



Special Sale Friic List (htitis and I'ust /Vic an 

 request to : — 



W. WATSON & SONS. 



313, HIGH HOLBORN, 



LONDON, W.C. 



1^1^ 16, FORREST RD., EDINBURGH. 

 '- 2, EASY ROW, BIRMINGHAM. 



ESTABLISHED 1837. 



ICKARD 



.^^^ 



TIME AND INSTANTANEOUS SHUTTER. 



The First, the Best and Most Perfect. 



Is now ''iipolied to order fitted with 

 NEW PATENT DISAPPEARING CORD. 



In this improved device tlie cord runs back 

 into the shutter box after the blind iB set either 

 for focussing or exposure, thus entirely obviating 

 all risk of its becoming entangled. 

 Shut*er from 14;6. Disappearing Cord 3/G extra. 



CATALOGUE POST FREE. 

 THE THORNTON-PICKARD MANUFACTURING 



CO., LTD., ALTRINCHAM. 



DENT'S CLOCKS, 



WATCHES, AND CHRONOMETERS. 



FOR SCIENTIFIC USE. 



Sidereal or Mean Time Clocks for 

 Observatories, £21 and upwards. 



E. DENT & CO., Ltd., 



WATCH, CLOCK & CHRONOMETER UAKERS 



I'.y Specia.1 .\ppolntroent to H.M, the Kin^. 

 Makers of the Great West- 

 minster Clock, Bijf Ben. 

 Makers of the Standard 

 Clock of the Royal Ob- 

 servatory, Greenwich, and 

 the Principal Observatories 

 throughout the world. 



o,,,;:^^.,- TRADE MARK 



61, STRAND, and 4, ROYAL EXCHANGE, LONDON. 



BEST 

 COCOAI 



earthJ 



GUARANTEED ABSOLUTELY PURE SOLUBLE COCOA ONLY. 



KING, SELL &OLDING, Ltd.. 



-^1- PRINTERS &'PUBLISHERS .|e^- 

 27, Chancer y Lane , LONDON, W.C. 



Special facilities for the printing and 

 publishin;; of Scientific Books, etc. 



Also for the printing of Scientinc and Optical Instrument Catalogues. 



IS£ Illustrations 



in this %(fnXXinl 



areb,|Vg0URNE&G 



73. 1 UDGATE HiLL eg. 



PHOTO-ENCRAVERS, ARTISTS, 



WOOD ENGRAVERS, ETC. 



ASK FOR QUOTATIONS & SPECIMENS. 



