September 4, 1914 THE COLLIERY GUARDIAN. 499 WALKER BROS. (Wigan) Ltd., $ A PAIR OF COMPOUND CORLISS TWO-STAGE AIR COMPRESSING ENGINES. Air Compressing and Blowing Engines9 with LIGHT DISC VALVES to NEW PATENTS. WINDING TWIN TANDEM COMPOUND ENGINES. “INDESTRUCTIBLE” TYPE VENTILATING FANS for Steam or Electric Driving. WINDING. HAULING AND GENERAL MINING MACHINERY PAGEFIELD IRONWORKS, WIGAN. NEW BROAD STREET HOUSE E.C. WILLIAM COOKE & CO. LTD. Established 1866. ,W.C00KE8