December, 1910. 



KNOWLEDGE. 



Watsons Microscopes. 



British made at Barnet, Herts, with 5 years' guarantee. 



The long evenini^s will soon be with us and a reallv attractive 

 and intelligent hobliy or means of rccreali<in is wanted i>v nianv. 



Have you ever tried a WATSONS' MICROSCOPE? 



Vou have scientific tastes and inclinaiions or vou would not 

 read KuowUd^e, A Microscope is an ideal means of developing 

 such. The wealth of inlormation it reveals, the new world it 

 discloses, the never ending subjects wluch can be examined, 

 together with the comfortaltle use of it at the fireside render it 

 unequalled for home use. 



Watsons make more than 20 different Models 



At varying prices. They are noted for their permanent working 

 quality, and convenience of design. 



It is important that a Microscope Stand is selected to which 

 additions can be made as required. 



Watsons' "F" Edinburgh 

 Student's Microscope 



forms an admiralilc base for future 

 additions. It is a stand of the highest 

 class that always gives pleasure and 

 satisfaction. 

 _ It is of convenient size, has very rigid 



tripod fool, Watsons' Standard Lever 

 Fine -Adjustment; Diagonal Rackwork 

 for Coarse Adjustment. Large stage, 

 covered Ebonite. 



PRICE. 



Stand only 



Mahogany Case 



STAND "F" completely 

 tilted with Eyepiece, i" 

 and i/6" Parachromatic Ob- 

 jectives, in Mahogany Case 



8 7 6 



*F" Ed. Student's Microscoi'E, 



WITH COMl-OCND SlUSTAGE. 



Compound Substage and Mechanical 

 Stage can be added at any time. 



Full particulars of Watsons' Microscopes are ^iven in their 168 page 



Catalogue of Microscopes (2K). which with their booklet. " The choice 



of a Microscope." will be sent free on request. 



ASTRONOMICAL TELESCOPES. 



All interested in Astronomy should send for Watsons' Catalogue 

 (6K) which j^ives information about their instruments and the 

 celeiirated Watson-Conrady Objectives, post free on request. 



Watsons' Instruments may be purchased by progressive payments. 



SECOND-HAND 

 ASTRONOMICAL TELESCOPES. 



A list of Second-hand Telescopes is issued montiily. A copy wlli be 

 sent on application. 



6 inch Equatorial by Gnihh, with Clockwork 

 on Iron Column. Electric Illumination to 

 Verniers, Telescope for Vernier frtim Eye 

 End; original cost, £290. In fine condition 



4 inch Equatorial by Cooke &• Sons, on stout 

 Tripod Stand, with Struts. li inch Finder, 

 4 Astronomical and Solar and Pancratic Eye- 

 pieces, Clamps and Slow .Motions ; complete 

 with Packing Cases Cost £77 10s. Od. Price 



24 inch Reflector Telescope by Gruhb, Equa- 

 tiirial Stand, Electrically controlled Clock. 

 Fitted with 6 inch Finder Telescope. Cost 

 £650 Price 



SJ inch Reflector Telescope, with 2 Finders, 

 F^quatorial Mounting and Iron Stand. The 

 Mirror has recently been re-worked and the 

 performance is guaranteed. A bargain 



£185 



£50 



£375 



£35 



For full Particulars of the ahoz'c, also of atany others^ 'with sundry accessories 

 ami fittings^ apply to 



W. WATSON & SONS, L° 



(Established 1^37). 



313, HIGH HOLBORN, LONDON, W.C. 



Works: BARNET, HERTS. 

 Branch: 16, FORREST ROAD, EDINBURGH. 



n<.nnt«- /2, Easy Row, BIRMING 

 uepois. -^jj^ swanston Street, M 



GHAM. 

 EUBOIRNE, AUSTRALIA. 



DENT'S CLOCKS 



WATCHES AND CHRONOMETERS 



FOR SCIENTIFIC tSE. 



Sidereal or Mean Time Clocks for 

 Observatories) £21 and upwards. 



THREE GRAND PRIZES 

 ANP ONE GOLD MEDAL 



FRANCO-BRITISH EXHIBITION. 



The onI>- Grand Prize awarded 

 to a British Firm for Watches, 

 Clocks and Chronometers. 



The only Grand Prize awarded 

 for Astronomical Regulators. 

 Chronographs, and Ship's 

 Compasses. 



TRADE MARK. 



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



Telephone So. 61 City, 



VOL' CAN OUTAIX A 



SATISFACTORY TYPEWRITER 



For £5. 



All Makes— over 200 Machines to Select from. 



CM or Write . . . 



THE WHOLESALE TYPEWRITER Co., Ltd., 



22, GRAY'S INN ROAD, W.C. (Eleven Doors from Holborn . 

 COPYING AND DUPLICATING AT SPECIAL PRICES. 



BEST 

 COCOAI 



EARTH 



GUARANTEED ABSOLUTELY PURE-SOLUBLE COCOAONLV 



