One notable feature of the G&SWR’s locomotive stock was its aversion to tank engines.
As the GD&CR was always intended to merge with the former its engines were allocated numbers following on from the GPK&AR sequence.
In 1878 Hugh Smellie introduced an ‘R’ list to cater for older engines whose number had been allocated to a newer one.
The G&SWR locomotive stock fell foul of the London, Midland and Scottish Railway policy of standardisation following the grouping.
Within ten years nearly 80% had been withdrawn from service and only a single 1 Class 0-6-2T engine remained by nationalisation in 1948.