NEW PATTERN FORTIN'S STANDARD BAROMETER Registered Design No. 470,297. As will be seen by the illustration, this Barometer is built on original lines. By the absence of the ordinary tubular enclosures in the usual form of instrument) the mercurial column is FULLY EXPOSED to view, NO SHADOWS are thrown upon the column, and therefore an extremely accurate and instantaneous reading is made possible. The scales being graduated upon the flat side peces he 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 10 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 Baroineter of the same dimensions. It yields readings equally close as the bighest priced instruments. Price complete, mounted on handsome Polished Solid Mahogany Board, with Brackets for Suspension, and Opal Glass Reflectors, £7 10s. Od. SMALLER SIZE, “THE STUDENTS," designed for Schools for demonstration work, and small private Ob-ervatories; bore 25 ; reading tu 01 inch and 1 millimetre. 23 7s. 6d. Results 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. Pulsometer Engineering Como Vine Elmoilronworks. Reading Sole Manufacturers and Proprietors of the Regd. Design: 46 HATTON GARDEN, LONDON, E.C. WHOLESALE MAKERS OF ALL KINDS OF METEOROLOCICAL INSTRUMENTS Telegrams: RAPKIN, LONDON. Nat. TEL.: 1981 Holborn. Estd. 150 years. 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