For the operation of their London suburban lines, the LSWR planned to purchase small, three-axle tank locomotives. Between 1852 and 1859, Joseph Hamilton Beattie had a total of 26 tank locomotives of different designs built in order to determine the optimal design. Although some of the locomotives also had the 2-2-2T wheel arrangement, the choice fell on the 2-4-0T wheel arrangement and a driving wheel diameter of 66 inches. This ensured good acceleration, but also sufficient speed on sections with larger distances between stations.

Between 1863 and 1875 Beyer, Peacock & Co. built 82 locomotives. By 1872 the LSWR had built three more in their own workshops at Nine Elms. The cylinder diameter of the first copies was 15 inches, this was later increased to 15.5 and then to 16.5 inches. The last twelve locomotives again had cylinders with a diameter of 15.5 inches, but a stroke of 22 instead of 21 inches. The two water tanks were located above the leading axle and under the driver's cab floor. Since this design is referred to as “well tanks” in the English-speaking world, they were given their well-known nickname.

From 1890 they were pushed out of their original area of operation because more powerful tank locomotives were now available on the London suburban lines. Outside the metropolitan area, their water capacity soon proved inadequate. A total of 31 had been rebuilt into tender locomotives from 1883 onwards. The largest part of the fleet was retired by 1899, of which only the three with the numbers 298, 314 and 329 from the construction years 1874 and 1875 were spared.

Preserved No. 0314 at Buckinghamshire Railway Centre

Oxyman

These three came to the Bodmin and Wadebridge Railway in Cornwall, which carried kaolinite or “China Clay” to the main line. They underwent extensive modernization, including the addition of a cab. All three came to British Railways, where they were considered the oldest locomotive type still in use, if not the oldest locomotives at all. Two of them were preserved after they were retired in 1962 and are still operational today.