After the introduction of steam railmotors, the LSWR had found out that they were often underpowered in times with high traffic on the branch lines. So in 1906, Drummond designed a small 2-2-0T tank locomotive based on the power unit of steam railmotors, but with more power. Ten were built as class C14 and used on push-pull trains. Usually coupled to two coaches, they still proved to be underpowered on some lines.

In 1910, two more class S14 locomotives were built after the same general design, but with four coupled wheels and enlarged boiler and cylinders. But as these were still less powerful than three-axle tank locomotives, no more were ordered. Anyway, Robert Urie ordered four of the class C14 also to be rebuilt to S14. Before the war, only two were completed.

In World War I, most were sold either to the Ministry of Munitions, to the Admiralty or the War Department and used as light shunters. After the war, two unrebuilt and one rebuilt C14 were still existing. In 1922 and 1923, the two remaining ones were also rebuilt. All three came first to the Southern Railway and then to British Railways. Their withdrawals came in 1957 and 1959.