Douglas The Scottish Mixed-Traffic Tender Engine

Douglas were designed by John F. McIntosh and built by the St. Rollox Works for the Caledonian Railway in 1909. Upon nationalisation, they became part of the Scottish Region of British Railways, where they were renumbered 57646 and 57647. In 1959, Sir Topham Hatt needed a goods engine and by his request, BR decided to transfer 57646 (Donald) to Sodor.