Ixxiv NATURE [OcToBER 16, 1913 
Leitz PORTABLE EQUATORIAL 
LARGE TRAVELLING MICROSCOPE 
conforms in its dimensions and general design to Model D. It is fitted 
with the new form of fine adjustment, having continuous cam and worm 
screw movement with milled heads at the sides. This mechanism, after 
several years of practical test, has proved to be superior in action and 
more durable than bs micrometer screw. FOR 3” TELESCOPES. 
Light but Firm. 
Easily Manipulated. 
STAND AND 
MOUNTING, 
£15 15s. 
or 
with 3” Tele- 
scope, 
£30. 
- SE MEITE WERZLAR 
[Illustrated Catalogue, 
Price, complete in case, with Abbe condenser, iris diaphragm Part I., Gratis. 
and worm focussing screw, triple nosepiece, objectives 
4” and #. evepieces I. and II. ... A a Pei) iets 4) 
Ditto and /,” oil immersion objective and eyepiece IV. 1710 0 
Ditto dittorand mechanical stage a as: Sa 21 00 J. H. STEWARD, Ltd., 
Ditto ditto ditto and dark ground condenser... Hepp nee 231 0 4 
Sectional Catalogues post free. Opticians & Scientific Instrument Makers to the British & Foreign Govts., 
18 BLOOMSBURY SQUARE, W.C. 406 & 457 STRAND, LONDON. 
(A few doors from the British Museum). EsTABLISHED 1852. 
? have a world-wide reputation for Class and 
Laboratory Work. They are unequalled for 
rapidity, accuracy, and durability. 
British made at Barnet, Herts. Guaranteed for 5 Years. y 
THE ‘RESEARCH ” MICROSCOPE 
is of the size, design, and workmanship that give finest results with continuous working. Its many conveniences suit it for all classes of work: with 
high or low powers, for original research or photography. It has :—Two inches of movement to the coarse adjustment for low-power work. 
Large top plate to stage. Mechanical stage with movements of 1}” horizontally and 1” vertically. Milled heads controlling move- 
ments of the stage work on the same axis. Vertical lever, side limb fine adjustment. All working parts are slotted and sp: 
so that the smoothness of movement which characterises WATSON MICROSCOPES may be maintained for a lifetime. 
PRICES :—Research Microscope, as figured and described, Stand only ... = wiss ae * ae “a4 gn . £12 oo 
Ditto with 2 Eyepieces, Objectives 2/3” and 1/6” N.A. 0.74, with t millimetre working distance, 
new aplanatised Abbe Illuminator with Iris Diaphragm, Double Nosepiec2. complete in Mahogany Case - £17 1 
WATSON'’S 1/12” Oil Immersion Objective, r'30 N.A., gives a flat field and exquisite definition ... div eos £5 
WATSON’S MICROSCOPE CATALOGUE ALSO GIVES DETAILS of Blood Counting Anparatus, Instruments for Bacteriology, &c. 
Copies will be sent gratis on request. ‘ 
W. WATSON & SONS, Ltd. (7°4837"**), 313 High Holborn, London, W.C. 
Optical Works—HIGH BARNET, HERTS. (2 EASY ROW, BIRMINGHAM. 
Branches {16 FORREST ROAD, EDINBURGH. Depots | 212 NOTRE DAME STREET, MONTREAL, CANADA. 
(184 GREAT PORTLAND STREET, LONDON, W. \78 SWANSTON STREET, MELBOURNE, AUSTRALIA. 
ae ee 
wh: "FOR ALL PURPOSES. 
Fu FINEST WORKMANSHIP AND FINISH. 
177, Oe 
& J 
EXCELLENT DEFINITION. sex 
PRICE LIST: ON APPLICATION. | 
SOLE AGENTS FOR GREAT BRITAIN AND IRELAND (EXCEPT LONDON). “4 
} 
{ 
STANDLEY BELCHER& MASON, L1.,. | 
CHURCH STREET BIRMINGHAM. | 
Printed by Ricuarp Cray & Sons, Lrwrrep, at Brunswick Street, Stamford Street, S.E., and published by MACMILLAN AND Co., Limtrep, at 
St. Martin's Street, London, W.C., and THz Macmittan Co., 66 Fifth Avenue, New York.—TuHuRsDay, October 16, 1913. 
