1899, Prussia ordered a short series of eighteen De Glehn passenger locomotives that were designated S 7 class. The most numerous series in the world was the Prussian P 8 passenger locomotive, later the DRG class 3810-40, of which 3,556 were built for the Prussian state railways and German railways between 1906 and 1923. Of these, 627 locomotives were given to other countries after the First World War. When exports and licensed production in Romania are included, their number reached almost four thousand. (Also see Poland) Prussia only started to operate express locomotives of its S 10 family from 1910. While they were externally similar, they differed in engine arrangement. The S 10 quadruple (4-cylindre, single expansion) of which 202 were built from 1910, later the DRG class 170-1. The S 101 4-cylindre compound, of which 237 were built in two batches from 1911 and 1914 (with pre-heater), later the DRG class 1710-12. The S 102 3-cylindre, of which 124 were built from 1914, later the DRG class 172. Saxony From 1906, Saxony used express service locomotive classes XII H, XII HV and XII H1, of which 6, 42 and 7 were built respectively. They later became the DRG classes 176, 177 and 178 respectively. All were superheated steam locomotives, differing mostly in engine arrangements. More numerous were the Saxon XII H2 class passenger locomotives, of which 169 were built from 1910. They later became the DRG class 382-3. Württemberg From 1898, the Royal Württemberg State Railways used D class passenger locomotives. It was also a four-cylinder compound locomotive, of which fourteen were built. Ireland The only Irish railways to use the 4-6-0 type were the Great Southern & Western Railway (GS&WR) and its larger successor, Great Southern Railways (GSR). The GS&WR had 4-6-0s for both fast freight and express passenger service. The culmination of Irish 4-6-0 design was the GSR Class 800 or B1a class, introduced in 1939. Three of these locomotives were built for top express passenger work on the Dublin-Cork mainline, coincidentally resembling the United Kingdom's Royal Scot Class as rebuilt. They were the last new steam locomotives to be built for the GSR. New Zealand The New Zealand Railways Department built its first home-built tender locomotives in 1894, using the wheel arrangement. Designated U class, they were supplemented by units built in the United Kingdom, which were sub-classed Ua. More were built in two batches in