 In 1915, another two Class A locomotives were built from spare parts.The Natal Government Railways (NGR) Class D tank locomotive was designed by William Milne, the Locomotive Superintendent of the NGR from 1877 to 1896, and was built by Dübs and Company.The first 46 locomotives, with an operating boiler pressure of and numbered in the range from 49 to 94, were placed in service during Milne's term.