The Standard Well Tanks were introduced by Joseph Beattie on the LSWR in 1862 as a result of the rapidly expanding network of the railway. The design can be traced back to the 'Nile' class of 2-4-0 well tanks of 1859, but were modified by Beyer Peacock in collaboration with the LSWR. Six of the engines were ordered for working the LSWR trains on the West London Extension Railway. They were so successful that by 1875 a further 79 had been built, all but three coming from Beyer Peacock's works. Of the three which eventually ended their lives at Wadebridge, N°298 (BR N°30587) and N°314 (N°30585) were built in 1874 and N°329 (N°30586) was built in 1875.

Representatives of the class worked over lines over most of the LSWR although in early years most were concentrated in the London area. A few of them carried names in those early years when LSWR engines had appealing names. The five named were N°33 Phoenix, N°34 Osprey, N°36 Comet, N°44 Pluto and N°76 Firefly.

When built all locomotives had the high-domed firebox typical of early Victorian locomotives, but Williams Adams began to replace these fireboxes with conventional coal-burning fireboxes when he came to office. This was a slow process and by 1886-9, with the Beattie fireboxes worn out, 12 of the original 85 were withdrawn from service. Around this time, injectors replaced the donkey pumps, with the feedwater heaters removed, although N°314 retained its donkey pump until rebuilt by the Southern Railway in 1931.

The introduction of Adams class 415 4-4-2 tanks (Radials') in 1883, saw the need for the well- tanks in the London area reduced considerably. Thus 31 of the class were given tenders to become standard 2-4-0 locomotives. As newer and larger locomotives were introduced, particularly the Adams O2 class, the need to keep so many of the well tanks was reduced and gradually their numbers were cut back in the 1890s.

Until the North Cornwall Railway, an independent concern operated by the LSWR, reached Wadebridge in 1895, the LSWR's Bodmin and Wadebridge line, with its Wenford Bridge branch remained isolated. Two years prior to this, one of the well tanks, no 248 was sent by sea to Wadebridge to replace the ancient and worn-out Fletcher Jennings 0-4-0 saddle tank, Bodmin. By 1895, N°44, N°266 and N°298 were working the Bodmin and Wadebridge lines. By the end of 1899 only the last three well tanks of the class remained, all the others having been withdrawn as they become worn out and redundant.

So things remained unchanged on the Bodmin & Wadebridge, through the Great 'War to end all wars', largely forgotten by the rest of the LSWR system. By 1921, the boilers of all three locomotives were almost worn-out. Because of the uniqueness of the Wenford Bridge line, with its very tight curves, replacing the well tanks of the services was not an option, so three new boilers of the 1907 Drummond O2 pattern were built, with N°298 and N°329 receiving injectors.

In 1929 a trial of the SECR P class 0-6-0 tank, N°558, was carried out on the line, but the track was damaged by its longer wheelbase. So the previously condemned 329 was reprieved. The next crisis came in 1931, with frame fractures to N°314, but it was rebuilt with modified frames, as were N°298 and N°329 later. Renumbering took place by adding 3000 to their numbers in May 1933 and so things continued as before right through to BR days, when they acquired their BR numbers. Their last general repair was in 1960 when they received their BR classification 0P.

By chance, three unique, but more modern, ex-GWR 0-6-0 small pannier tanks, N°1367/8/9, became redundant around the docks of Weymouth in 1962. Under the regional reorganisation of 1958, the Southern Region had regained control of the lines around Wadebridge as well as taking over the ex-GWR lines around Weymouth. As a consequence the opportunity was taken to send the three Western Region tank engines down to Cornwall, and bring to an end 70 years of historical working.

Two have been preserved. N°298, now 30587, was a static exhibit under cover at the South Devon Railway at Buckfastleigh but was moved in December 2001 to the Forest of Dean where she has since been restored to full running order and is now based on the Bodmin & Wenford Railway. N°314, now 30585, was overhauled to running status at the Buckinghamshire Railway Centre at Quainton Road.