|Sentinel 7109 (Joyce) in 1964 (photo C Verrall)|
Its central section houses a four inch thick cast-iron water tank to provide ballast as well as hold water. Whatever the water level in the tank, the weight distribution remains the same and so the loco is balanced front to rear. Some Sentinel loco designs had the tank at one end and so were only balanced at one particular water level!
7109 was the first of eight pre-war locomotives of this type. Test results gave sufficient confidence for two similar units to be purchased by the Somerset & Dorset Joint Railway Company for use at Radstock. It is being restored at Midsomer Norton station, about a mile or so from Radstock, and so it is in as good a location as any to trigger memories of the once familiar Radstock Sentinels.
Sentinel Waggon Works Building in November 2009