Worksplate Ruston & Hornsby Loco number 181816. Ex 4wDM, 20HP, 2' Gauge locomotive built at the Boultham Works on 18th November 1936. Supplied new to Corsham storage depot which was adjacent to Box Tunnel on the Swindon - Bath line. Sold to Penrhyn Quarries, Bethesda in January 1948.