During the Second Boer War, the British troops urgently needed powerful tank locomotives. Since the Natal Government Railways had already procured a ten-coupled tank locomotive from British production, the Reid Tenwheeler, they used this design and ordered 35 units as well. The order was divided between Dübs and Neilson, Reid in order to achieve a larger number in a short time. A visible difference to the NGR locomotives was the weatherboard on the coal bunker, which also offered protection from the elements when reversing. The military machines also attracted attention due to the brass parts on the boiler that were always polished to a high gloss.
after the rebuild to 4-8-2T
archive SAR 
The first and fifth coupled axles were designed without wheel flanges for better maneuverability, which, however, was fatal to the locomotives in some situations. Especially when reversing, there were often derailments when entering tight curves or switches because the leading coupled axle had no wheel flanges. One attempted solution was to widen the wheel tyres, but this had only limited success. Despite this problem, the engines provided valuable service during the war until they came to the CSAR at the end of the war.
after the rebuilt to 4-8-0TT
Locomotive Magazine, December 1905
In order to really improve negotiation of curves and prevent derailments, it was decided, like the NGR, to remove the fifth coupled axle and thus convert six of the locomotives into a 4-8-2T wheel arrangement. A very large distance between the fourth coupled axle and the trailing axle was now visible, and the load on the trailing axle increased from just over four to just over six tons. With the formation of South African Railways they became Class E as tank locomotives were designated with letters. They were mainly used for shunting and were retired by 1966.
A sample of the former 4-8-0TT without side tanks in November 1974 in the Albion Mines
Dennis Mitchell 
Another conversion was made in 1904, initially on one engine that was intended to increase the range that was too short in the eyes of the SAR. The last coupled axle and the trailing axle were removed together with the coal bunker, the frame was shortened accordingly and an additional tender was attached. Since the water tanks on the sides of the boiler had been retained, it was the design known in English-speaking countries as "Tank and Tender" with the wheel arrangement 4-8-0TT.
Since the second rebuild was successful, all remaining 28 engines were rebuilt in the same form and provided with surplus three-axle tenders. With the SAR they received the class number 13, since tender locomotives were designated with numbers. They were mostly used in the Witwatersrand region, where they were nicknamed “wallopers”, which means “wall runners” in Afrikaans. After their decommissioning, which was completed by 1961, some examples were sold to various mine operators. Some of these locomotives were used until the 1980s, after the side tanks had been removed from some in the meantime.