Lady Madcap
From Festipedia, hosted by the FR Heritage Group
Usually recognised as a Hunslet quarrry tank although it was built for the Groby Granite Co in Leicestershire before coming to the Dinorwic State Quarries.
The orginal locomotive (Hunslet 652 of 1896) was dismantled from the 1950s and although a number of parts have been collected at Gelert's Farm for the reassembly of the locomotive, new frames have been manufactured, making it technically a new locomotive under construction (2005).
See the WHRL site for more information