Peter Kerslake says "A long standing resident here at Bristol St. Philips Marsh Motive Power Depot "5600" class "Taffy Tank" number 6670 had been one of the last fifty of the one hundred strong second batch of the class built by Armstrong Whitworth during 1928 at their Scotswood on Tyne factory, the initial 150 having come from Swindon.
The depot here at Bristol's St. Philips Marsh comprised of two Roundhouses dating from 1910 and in B. R. days was home to a substantial number of Mixed Traffic and Freight locomotives.
Upon the closure of Bristol's Bath Road passenger locomotive Depot in September of 1960 in readiness for its new role as a Diesel Depot the remaining steam locomotives there were transferred across to St. Philips Marsh and then four years later in June of 1964 when that Depot also closed its whole remaining allocation was moved to the former Midland Region Depot at Barrow Road for just a year until the end of Western Region steam in December 1965."