The sixteen examples of this class were designed by James Stirling for the GSWR and were built at Kilmarnock Locomotive Works (Works Nos. 49 and 54-67) between 1868 and 1870. They were numbered irregularly, and not in chronological order between 8 and 183, to fill gaps in the sequence of running numbers.[1] The members of the class were fitted with domelessboilers and a cut away cab. They were fitted with spring balance type safety valves, but this was replaced by those of the Ramsbottom design over the centre of the boiler.[1]
Withdrawal
The bulk of the class, including all the rebuilds were scrapped between 1900 and 1905 but two survived until 1913 and 1917 respectively.