The London, Brighton & South Coast Railway had relatively light express trains on the London to Portsmouth line, which were still pulled by Singles in the early 1890s. Since these had reached their limits, Robert Billinton developed the first LB&SCR locomotives with a leading bogie. Between 1895 and 1898 25 were built in Brighton, designated class B2.

The nickname “Grasshopper” is probably a reference to unsteady running characteristics. Since their power was described as too low for their tasks, Billinton had the B3 “Bessemer” built in 1897 with a larger boiler. There were initially no modifications to the existing locomotives und also the ones built until 1898 got the original boiler.

It was only Marsh who had all B2 and B3 rebuilt from 1906 onwards with the same boiler as the class C3 freight locomotives, which became class B2x. This boiler was heavier, but had a smaller heating surface and still achieved greater output. The B2x was phased out with the electrification of the line to Portsmouth between 1929 and 1933.