and more ornate boiler-mounted sandboxes. They also had round-top fireboxes, outside plate frames and used Walschaerts valve gear. Service Natal Government Railways The Hawthorn Leslie Side Tanks were acquired specifically to work the Donnybrook-Esperanza railway. When they were delivered in 1907 in anticipation of the opening of the Donnybrook line the following year, they became part of the Class N on the NGR and were numbered in the range from 4 to 9. South African Railways When the Union of South Africa was established on 31 May 1910, the three Colonial government railways (Cape Government Railways, NGR and Central South African Railways) were united under a single administration to control and administer the railways, ports and harbours of the Union. Although the South African Railways and Harbours came into existence in 1910, the actual classification and renumbering of all the rolling stock of the three constituent railways were only implemented with effect from 1 January 1912. In 1912, the NGR narrow-gauge locomotives were included in the SAR's narrow-gauge numbering scheme, but were not classified or renumbered and merely had an "NG" prefix, for narrow gauge, added to their existing engine numbers. In 1915, shortly after the outbreak of the First World War, the German South West Africa colony was occupied by the Union Defence Forces. Since a large part of the territory's railway infrastructure was destroyed or damaged by retreating German forces, an urgent need arose for locomotives for use on the narrow-gauge lines in that territory. In 1917, three of these locomotives, numbers NG4, NG6 and NG9, were transferred to the Defence Department for service in South West Africa. Numbers NG4 and NG9, and possibly all three locomotives, returned to South Africa after the war. A system of grouping narrow-gauge locomotives into classes was only adopted by the SAR in the late 1920s. At that point, the four remaining Hawthorn Leslie Side Tanks, numbers NG4, NG5, NG8 and NG9, were designated on the SAR. In SAR service in South Africa, the Class NG3 remained mainly confined to the Natal narrow-gauge branches. One exception was no. NG5, which was transferred to the Avontuur branch in the Eastern Cape in 1939 to replace Class NG9 no. NG45, which was in turn transferred to the Upington-Kakamas branch to join her two sister engines, numbers NG44 and NG46. In Port Elizabeth, no. NG5 was employed on yard duties in and around Humewood Road,