July 20, 1905 J 



NA TURE 



SPECTROSCOPE - REFRACTOMETER 



(as suggested by, and made for, 

 R. APPLEYARD, Esq.) 



Telegraphic 



Address: 

 SPHERICITY, 

 LONDON." 



Jhi5 new instrument is a Gonio- 

 meter, Spectrometer, and Refracto- 

 meter coml)ined ; and is an 

 accurate and efficient instrument 

 in any of tfiese capacities. As a 

 Refractometer {Pulfricli type) it is 

 a rapid and convenient instrument 

 for measuring the refractive indices 

 of transparent solids and liquids. 



ILLUSTRATED LIST ("A") OF SPECTROSCOPES AND ACCESSORIES GRATIS. 



ILl^IL'JVL HEILGSR, IL,td., 75a Camden Road, London, N.W. 



AWARDED GOLD MEDAL ST. LOUIS EXHIBITION, 1904. 





All other air 

 pumps superseded. 





THE. 



"GERYK" 



(Fleuss Patent) 



Vacuum Pump. 



R.esults hitherto only pos» 

 sible with mercury pumps 

 are readily obtainable by 

 the " GeryK." Used by 

 all leading scientists. Far 

 more rapid than any other 



vacuum pump. 

 Price from Write for 



£4:5:0. LIST F.45. 



puUoi 



.metct €n9ineering Q2Xi 

 QiM etmtbemvoTks. R.eading. 



AWARDED MEDALS WHEREVER EXHIBITED, 



including 9 at the great Paris Exposition of iqod. 



JAS.J. HICKS, 



WHOLESALE MANUFACTURER OF 

 SCIENTIFIC AND CHEMICAL APPARATUS 



WAR OFFICE, INDIA OFFICE, ADMIRALTY, 



ROYAL COLLEGE OF SCIENCE (LONDON), 



GOVERNMENT LABORATORY, 



MANCHESTER SCHOOL OF TECHNOLOGY, &c., &C. 



HYGROMETER 



and 



THERMOMETER. 



ANY KIND OF SCIENTIFIC INSTRUMENT MADE TO ORDER. 



Prompt Attention to all Orders and Inquiries. 

 -sm- EXCEPTIONAL TERMS TO COLIECES, INSTITUTIONS, &c. 



Quotations subinittid for Laboratory Outfits or Single Instruments. 



THERMOMETERS FOR STUDENT WORK A SPECIALITY. 



Catalogues Post Free. (State which required.) 



8, 9, & ID HATTON GARDEN, LONDON. 



