NATURE 



[July 20, 1905 



VAPOUR PRESSURE 

 APPARATUS. 



A convenient modification 

 of Regnault's classic 



form. 

 The barometer tubes 

 are of syphon form, and 

 are completely enclosed 

 in a brass water-bath 

 with plate-glass inspec- 

 tion windows. 



Price complete (with- 

 out Mercury), 



iS5 : 5 O. 



nXITE FOB DESCRIPTITE 

 PAMPHLET. 



The Cambridge Scientific Instrument Co., Ltd., 



CAMBRIDGE, ENGLAND. 



JOHN J. GRIFFIN & SONS, 



MANUFACTURERS OF 



SCIENTIFIC APPARATUS. 



Complete Equipments 



in 



Apparatus & Chemicals 



FOR CHEMICAL, 



BACTERIOLOGICAL, 



ELECTRO-CHEMICAL, 

 METALLURGICAL, 



AND AGRICULTURAL 

 LABORATORIES. 



SARDINIA ST., LONDON, W.C. 



FORTIN'S 

 STANDARD BAROMETER 



Registered Design No. 42 

 As will be seen by the illustration, 



built on original lines. 



By the absence of the ordinary tubula 



usual form of instrum 



EXPOSED to view 



the column, and thei 



stantaneous reading 



graduated upon the fla 



this Baromete 



enclosures (in the 

 t) tbe mercurial column is FULLY 

 NO SHADOWS are thrown upon 

 efore an extremely accurate and in- 

 is made possible. The scales being 

 t side p'eces the DIVISIONS AND 

 FIGURES" ARE ALWAYS IN VIEW, and the vernier 

 is very much more legible than in the ordinary tubular 

 patterns. 



The bore of the tube is 0*5 inch. 



The scales are graduated in inches and millimetres, and, 

 by means of the verniers, are capable of being sub-divided 

 to read to 0'002 inches and 0' 1 m/m. 



The attached Thermometer on the body of the instru- 

 ment is graduated in Fahrenheit and Centigrade scales. 

 It is the BOLDEST Standard Barometer made. 

 The PRICE IS LOWER than that of any other form 

 of Standard Barometer of the same dimensions. 



It yields readings equally close as the highest priced 



Price complete, mounted on handsome Polished 

 Solid Mahogany Btoard, with Brackets for Sus- 

 pension, and Opal Glass Reflectors, 



£7 IDs. Od. 



SMALLER SIZE, "THE STUDENTS," 



designed for Schools for demonstration work, and small 



designed for Schools for demonstration work 



private Observatories; bore -25 ; reading to '01 inch 



and M millimetre. 



£3 7s. 6d. 



ill 1 Str/e Maniifnctuyers ami Pro/irhtors of the Rigd. Design: 



^'^ PASTORELLI & RAPKIN, Ltd., 



■:l^ 46, HATTON GARDEN, LONDON, E.G. 



^' Wholesale Makers of all kinds of Meteorolooical Instrumehts. 



Telegrams : Rapkin, London. Nat. Tel.: 19S1 Holborn. Estd. 150 years. 



W.H.SMITH ISDN'S 



LIBRARY 



EMBRACES ALL THE MOST IMPORTANT BOOKS, 



BIOGRAPHIES AND MEMOIRS, TRAVEL AND SPORT, 



HISTORY, THEOLOGY, SCIENCE AND SOCIOLOGY, 



NATURAL HISTORY, LITERATURE AND ART, POETRY 



AND ESSAYS, TOPOGRAPHY, FICTION, REVIEWS, 



AND MISCELLANEOUS WORKS. 



The newest and best books of popular interest are 

 added as published. 



The books are delivered to the Bookstalls to Sub- 

 scribers' orders, carriage paid. 



Over 800 branches to which Subscribers can be trans- 

 ferred. 



Special Travelling Subscriptions entitling Members to 

 exchange at any branch without previous notice. Terms 

 on application. 



Books exchanged by Parcels Post, Rail, or other 

 means from the Head Office to any part of the United 

 Kingdom. Boxes supplied gratis. 



Prospectus and list of recent books in circulation and 

 any other information can be obtained upon application. 



A catalogue of Surplus Library and New 

 Remainder Books, offered at greatly reduced prices, 

 is published monthly, and supplied gratis on application. 



o^#.^^T1l8rSTRAND7i^0N, W.C. 



BRANCHES at all the Railway Bookstalls. 



