July 20, 1905J 



NA TURE 



NEW COMPRESSOR 



For RAOIOGRA.PMY, &ic. 



Fittea withes '~.v:i /^,^^ Adjustable 



" Burgess" Patent i^'J Diaphragm. 



Unequalled for ASTRONOMY, NATURAL HISTOR 

 and General Observations. 



) fitted with a protected lead top, and is so 

 that it can be moved in any position and at 3ny angle. Lead gla 

 instead of metal, and the Glasses can be supplied of various sizes. 



The " Burgess " Diaphragm, with which the Compressor is fitted, can 

 be adjusted by a slight movement from an aperture of 4 in. to \ in. 



The Tube is held in a special form of Holder, ensuring absolute rigidity, 

 and can be raised or lowered. 



Price of Compressor with one Glass, £7 10 O. 



E.xtra Glasses, each, £0 18 6. Price of Diaphragm, £2 5 O. 



( I'he Ci'iii/'ressor tan he made to fit any Couch if desired.) 



la R03EBERY AVENUE, k 15-21 LAYSTALL ST., LONDON, E.C. 



G. BOW RON, 



57 EDGWARE ROAD, LONDON, W.^ 



h.is alw.iys on hand a K.rj.; and varied stock of 



SECOND-HAND 



APPARATUS 



EXTREMELY 



uppHed to the National Pby- 



1 Laboratory; Aberdeen, Aberystwyth, 

 d Glasgow Universities ; Bedford, Bradford, 

 id Yorkshire Colleges ; and twenty other Scientific 

 nstitutions, Polytechnics, &c. 



!•" Nature says: "Teachers requiring 

 cost for lecture or laboratory purposes, i 



iffici 





light consult tht 

 in^ Nature. 



at a low 

 list with 



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 & CHFiONOMETER MAKERS 

 By Special Appointment to H.M. the King. 



STER Clock, 



Ollh/ Irlil 



61 STRAND, and 4 ROYAL EXCHANGE, LONDON. 



NEW PRISM 

 BINOCULARS. 



(LONDON MADE.) 



i^ £5 



10 



£610 



X 12 



£715 



SPECIAU FEATUI5ES — 



I. — Optical excellence. 

 2. — Strength of construction. 



3. — Light weight, owing to special metal used in the bodies. 

 4. — Price within the reach of those requiring good Field 

 Glasses for all purposes. 



A. E. STALEY & CO., 



19 THAVIES INN, HOLBORN CIRCUS, LONDON, E.C. 



Please Write for Booklet. 



The New Manifolding 

 Hammond Typewriter, 



A Hammond Typewriter will do anything any other 

 typewriter does— ond do it better. "Beside, it has 

 tiilenty exclusive features, not one ol which is possessed 

 by any other writing machine. 



WHY is the HiuiiiiKvid the Best Maehine for 

 Ste/ios^niphers '' 



BECA USE 



Perfect and Permanent 



Alignment, 

 Work in Sigllt, 

 .Manifolding, 

 Speed, 

 Durability. 

 Noiselessness, 

 Interchangeable Type. 

 Light Elastic Touch, 

 Perfect Paper Feed. 

 Any Width Paper, 



are essential requisites, and the Haininona 

 possesses them all. 

 On account of the TYPE being interchangeable, it is most 

 useful to SCIENTIFIC work. 

 Call and test Machine or write for Catalogue, free on appli- 

 cation to : — 



The Hammond Typewriter Co.. 



50 QUEEN VICTORIA ST., E.C. 



MANCHESTER BRANCH: 104 DEANSQATE, MANCHESTER. 



