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The Neilson works numbers were 4352–5, they were delivered in June 1891 as Metropolitan Railway nos. 67–70. Larger boilers were fitted during 1901–03, with the pressure increased to 150 pounds-force per square inch (1,030 kPa) as compared the 140 lbf/in (965 kPa) of the original boilers. No. 67 was sold in 1917 to the Ministry of Munitions; the others were sold in 1923 to Charles Williams of Morriston.