September, 1910. 



KNOWLEDGE. 



Watsons Microscopes. 



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



The long evenings will snon be with us and a really attractive 

 and intelligent hobliy or means of recreation is wanted bv many. 



Have you ever tried a WATSONS' MICROSCOPE? 



Vou have scientific tastes and inclinations or you would not 

 read K'tiowled^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 which can be examined, 

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

 unequalled fur home use. 



Watsons make more than 20 difTerent 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 



lurms an aiimirable 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 foot, Watsons' Standard Lever 

 Kine Adjustment; Diagonal Rackwork 

 for Coarse Adjustment. Large stage, 

 covered Ebonite. 



^%%^. 



% ikX^^ St.-n,donly £5 7 



' ll.,./^ Mahogany Cse 



6 

 1 



STAND "F" completely 

 tilted with Eyepiece, i" 

 and i/6" Parachromatic Ob- 

 jectives, in Mahogany Case 



8 7 8 



'1'" En. Student's Mccboscote, 



WllH CoMrOLNi) SLlt^T.Ai.K. 



Compound Substape and Mechanical 



Stage c.tti be ruUifJ 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 .\^tl■"n'nny .sliould send tur Watsons' C.xtalogue 

 (6K) which i;ivcs information about iheir instruments and the 

 celebrated 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 monthly, 

 sent on applicailon. 



A copy will be 



6 incli Equatorial by Gmh/i. with Clockwork 

 on Iron Column. Electric Illumination to 

 Verniers, Telescope for Vernier from ICve 

 End; original cost, £290. In fine conditif.n £185 



4 inch Equatorial by Cooke Ci^ Sons, on stout 

 Tripod Stand, with Struts. \h inch Finder, 

 4 Astronomical and Solar and Pancratic Eye- 

 pieces, Clamps and Slow Motions; complete 

 with Packing Cases. Cost £77 10s. Od. Price £50 



24 inch Reflector Telescope by Gnibb, Equa- 

 torial Stand, Electrically controlled Clock. 

 Fitted with 6 inch Finder Telescope. Cost 

 £650 Price £375 



SJ inch Reflector Telescope, with 2 Finders, 

 Equatorial Mounting and Iron Stand. The 

 Mirror has recently been re-worked and the 

 performance is guaranteed. A bargain ... £35 



For/uli particulars 0/ the abcvCy also o/ntanv others, with sundry accessories 

 aytii fittings, apply to 



W. WATSON & SONS, L" 



(ESTABLISHKD lS37), 



313, HIGH HOLBORN, LONDON, W.C. 



Works: BARNET, HERTS. 



Branch: 16, FORREST ROAD, EDINBURGH. 



n^nnt. 1 2. Ea.sv Row, lilRMINGHAM. 



uepois -^jg^ swanston Street, .MELBOIUNE, AtSTRALIA. 



DENT'S CLOCKS 



WATCHES AND CHRONOMETERS 



FOR 5CIENT11-1C LSU. 



Sidereal or Mean Time Clocks for 

 Observatories, £21 and upwards. 



THREE GRAND PRIZES 

 AND ONE GOLD MEDAL 



FRAN CO -BRITISH EXHIBITION. 



The only Grand Prize awarded 

 to a British Firm for Watches, 

 Clocks and Chronometers. 



The only Grand Prize awarded 

 for Astronomical Regulators, 

 Chronographs, and Chip's 

 Compasses. 



TRADE MARK. 



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



Telephone No. 61 City. 



V( ir 



AX 



SATISFACTORY TYPEWRITER 



For £5. 



All Makes— over 200 Machines to Select from. 



Call or Write . . . 



THE WHOLESALE TYPEWRITER Co., Ltd., 



22, GRAY'S INN ROAD, W.C. (Kleven Doors from Holl.orn\ 

 COPYING AND DUPLICATING AT SPECIAL PRICES. 



BEST 

 COCOAI 



^ SCHWEITZER S 



iocodtlna 



EARTH 



GUARANTEED ABSOLUTELY PURE SOLUBLE COCOA ONLY. 



.■■:'rgy?fpiiy-g:;;-..;; 



■S^'') 



&Ke fRINTeO FROM 

 PROCtSS BLOCKS MflOC BV 



MAYBURY STUDIOS, ^ 



WILLLSDEN GREEN, N.W. 



TCIUPHOUC No 4S. HARLE5DEN. 



■a^\^ /SPECIAL 



\ 



j^. 



SPECIALITY 



^SciiNTiFicSuma^/^^ 0\ 



4 07HER I llC^v 



hiUSTRmiONS, 





