 This number started out in 1881 on a 4-2-4T, the only tank locomotive built by the Great Western Railway with single driving wheels (though not the only tank locomotive operated by the Great Western, which inherited some from the Bristol and Exeter Railway), these being in diameter and had unusually large cylinders.It did little work as it was prone to derailing, indeed it did this in front of William Dean on its first trial move out of the shed.In 1884 it was rebuilt as a strange-looking 2-2-2 tender locomotive with outside Stephenson's valve gear.