Documents relating to the development of three-cylinder valve gears, collected by Harold Holcroft

"Southern Railway Locomotives 1923-1938" and " Locomotives of R. E. L. Maunsell, 1912-1937" by O. S. Nock, from The Locomotive, 15 March 1949; "D.58 Class Locomotives for New South Wales Railways" by G. H. Paulin, from The Engineer, 19 October 1951; "The Experimental Spirit; 4-Condensing; Valves and Valve Gears" by C. R. H. Simpson, from Engineering, 18 January 1957; "Valve Gears for Three Cylinder Locomotives" by Felix Meineke, translated and typed, no date given; Two plans showing three-cylinder valve gear set-ups, without annotations; Blueprint showing a number of graphs, tables and diagrams demonstrating aspects of the three-cylinder valve gear.