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Nos. 1, 6, 7 and 10, built between 1892 and 1896, had detail differences between them, Ahrons describes them as having a more modern appearance.
Locomotive No. 10 (St. Seneanus) was rebuilt as 2-4-2T in 1903. Nos. 28 (St. Lawrence), 45 (St. Kieran), and 46 (Princess Mary) were also rebuilt later in 1909/10.
On review following amalgamation into Great Southern Railways (GSR) in 1925, Nos. 1, 2 and 6 were promptly withdrawn despite No. 2 having received a new boiler in 1914. The remaining four engines Nos. 7, 9, 47 and 49 were designated GSR class 423/G1 and allocated the numbers 426, 424, 425 and 423 respectively. Unlike the other survivors, No. 426 had not been re-boilered in 1914–1916 and it was withdrawn in 1926.
References
Boocock, Colin (1 October 2009). "Locomotive Compendium Ireland" (1st ed.). Ian Allan. pp. 37, 40. ISBN9780711033603.
^ Clements, Jeremy; McMahon, Michael (2008). Locomotives of the GSR. Colourpoint Books. pp. 131–135. ISBN9781906578268.
Ahrons, E. L. (1954). L. L. Asher (ed.). Locomotive and train working in the latter part of the nineteenth century. Vol. six. W Heffer & Sons Ltd.