k ix 



A^A TURE 



[June 8, 1905 



GAIFFE IMPROVED 



WIMSHURST MACHINE. 



A Standard Instrument for Laboratory and 

 Research Work. Gives absolutely uniform con- 

 tinuous current for X-Rays, High Frequency, 

 Wave Current, &c. No enclosure (works in open 

 air), no spindle, no sectors. Plates are readily 

 detachable. - - - ^_ 



Descriptive Pamphlet gratis on application from the 

 Sole Agents for Great Britain and its Colonies— 



THE MEDICAL SUPPLY 

 ASSOCIATION, 



228 GRAY'S INN ROAD, LONDON, W.C, 



where the apparatus may be seen working. 



ox?.ossx<£:^v^'s €3i-j%.^ £::]^C3-i»irjE:s» 



RECENTLY 



REMODELLED. 



Represents K and L 



types, g:iving' 3*5 H.P. 



and 5 H.P 



respectively. 



Immediate Delivery 



for Stock Sizes 



of Ensines. 



GREAT REDUCTION 

 GAS CONSUMED. 



Up to the end of 1904, 



over 50,000 engfines 



have been delivered, 



representing- about 



three-quarters of a 



million actual 



horse-power. 



Cie.OSSlL.E'V" ]BR.OS., X.Tr>., OFE3VSHuA.^W", 3VCA.3VCHESTER. 



NEW AND BEAUTIFUL PREPARATIONS IN WATSON'5 UNIQUE COLLECTION. 





elopmen 



Ascidi; 



25 



A large 





I have 240 Micro. Slides on h 

 ■ ■ tificNovehy. 



Groups of Diatoinacea:, Spicules 



r<"duced prices ... 

 NEW Edition of Supplementary List of latest Micro, 

 now ready, post free, it give?; full particulars of our 

 series of Aquatic Organisms, &c., &c. 



Trypanosoma Brucei (Tsetse fly disease) » 



Malarial parasites — many phases 

 Radium for the Microscope. Mounted on a 3 x i 

 Micro. Object. Shows scintillations strikingly with I 



Objective. Quite new 



e from Watson & Sons' Cabinets. Send for particulars. 

 These buttons are made of polished steel upon which spiral lines 



Made 



8/6 to 



Objects 

 beautiful 



,. each 

 lip as a 



Very fine Sei 



' (Aspersa), 16 preparat ... ^.. 



Section through entire bud of Lily 



Beautiful Slides of Siephanoceros with cili 



according to perfection 



Lophopus crystallinus 



Vermes (Marine), various 



Section of precious Opal, with matrix (opaque) 



Section of Quartz with fluid cavities 



Lea/ of Pampas Grass— very pretty section ... 

 For a Guinea a year you cai 



NEW.-WATSON"S DIFFRACTION BUTTONS 



apart are engraved. A beautifully soft radiated appearance is imparted by these lines, the colours being in the order of the Sp' 



;;-inch diameter, 4/6 each ; 6 in case for 25/- ^-inch diameter, 2/6 each ; or 6 in case for 15/- 



Send foi Watson's Illustrated Catalogues of Microscopes (No. 2), Microscopic Objects (No. 3). Telescopes and Field Gl 



Post free on application 



/Established 

 1837 

 313 HIGH MOUiBORN^, LON^DON^, W.C 



BPanches-16 FORREST ROAD. EDINBURGH, and 2 EASY ROW. BIRMINGHAM. Awarded 42 Gold and other Medals. 



DALLMEYER'S TELE-PHOTO. LENSES & ATTACHMENTS 



Enable you to take Photographs of Distant nr Inaccessible 



Subjects of sufficient size to be of practical value. 

 |C- Indispensable for use in all departments of Natural 



History Field Work (especially Ornithologyi, and also 



to Architects. 



Price from £3 15s. 



W. WATSON & SONS, (' 



*) Opticians to H.M. Government, 



P'ii-es ail./ Parliitilars on application. Estimates and 



_ J. H. DALLWIEYER, Ltd., 



istigmatie Lens fitted with Tele-Photo. Attachment. ^5 Newman Street, London, W., 



]vi.ake:xss of 



(These Au^hnients can befitted to any good Lens.) THE CELEBRATED DALLMEYER LENSES. 





>fd by RiciiA^li-'OliAy Alio Sons, LlMi5EIV*t 7 & S bread Street Hill, Queen Vicr 

 AND Co.,L!MlTEl>,al Si. Martin's Street, Lonaon, W.C, and The Macmillan CoMf 



Street, 111 the City of Lcnaun, and published by Macmillan 

 , 66 Fifth Avenue, New York.— TntlRSDAV, June 8, 1(105. 



