April 1, 1915. THE COLLIERY GUARDIAN. 723 Hopkinson-Ferranti ------ PATENT ------ STOP VALVE For Steam and Higlx Pressure Water Service. The GREATEST ADVANCE in VALVE CONSTRUCTION of the TIMES. Less Weight, Cost & Leakage PRINCIPLE : Converting the pressure of the fluid into velocity and re=con= verting the velocity into pressure, thereby passing an amount of steam equal to full carrying capacity of pipe. SELLING POINTS: Passes the same quantity of steam as a full-bore valve. Seats half diameter of ordinary sluice valve, therefore halves possible leakage. Graded opening — no sudden rush of steam in opening. Is not subject to wedging action or mechanical strain. When the valve is open the seats are protected from the flowing fluid by the eyepiece. Always easy to open and close under pressure. __________ DISCS AND SEATS OF HOPKINSON’S “PLATNAM” METAL Suitable for Superheated Steam. 15,000 in use. Illustrated Specifications and Catalogue free on application. J. HOPKINSON t CO. L- HUDDERSFIELD, of Patent Valves and Patent Safety Boiler Mountings, 165, Queen Victoria Street, LONDON; 41, Bothwell Street, GLASGOW; 2, York Buildings, York Place, EDINBURGH; Royal Buildings, Park Place, CARDIFF; 7, Manchester Street, OLDHAM; PARIS and ST. PETERSBURG. No. 305.