The above picture provided from the records held on the Vulcan Foundry website
The original engine of this name dates from the beginning of the NWNGR. It survived to play a significant if rather inglorious part in the early history of the revival of the Ffestiniog Railway.
The original Moel Tryfan was a 14 ton single Fairlie 0-6-4T built in 1875 by the Vulcan Foundry in Lancashire (Builder's number 738 of 1875) for the North Wales Narrow Gauge Railways. Together with its mate, Snowdon Ranger, it was the first British 0-6-4T. They were named after the original outer termini of the NWNGR.
It went to Davies & Metcalfe of Romiley, near Stockport, for a rebuild in 1903. It seems that a fitter from Gorton Foundry (Beyer, Peacock) was engaged for the occasion.
An accident on the NWNGR in 1908 damaged one Fairlie, which seems to have been Snowdon Ranger because a new set of frame plates were ordered from Hunslet Engine Co. in that year. Some time after that event Moel Tryfan and its sister were amalgamated. Almost certainly this would have benefited from Snowdon Ranger's new frames, and as the combination carried Moel Tryfan's nameplates, it probably included the tanks of Moel Tryfan. The question is when did this happen ? An affidavit from Aitchison to the Chancery Division of the High Court in his roll as Receiver and Manager in January 1913 asked the Court to allow him to spend money on repairing Moel Tryfan and Russell, but he opened his request with the comment "Owing to the collapse due to age and wear of two out of the three locomotives belonging to this Railway . . . ." The third engine must have been Gowrie, implying that the "amalgamated" Fairlie had either gone or was not regarded as part of the working stock. Two spares orders for piston rings for slightly different sizes were ordered from Hunslets - for Snowdon Ranger in September 1910 and Moel Tryfan in February 1911, suggesting both were still both running then. Clearly one of the Vulcan Fairlies was regarded as being in poor condition in 1908 when the affidavit was sworn by Russell to purchase Gowrie - "in place of one of the original locomotives which has been running since the line was opened in August 1877" (i.e to Quellyn) However, Snowdon Ranger was photographed in June 1909, so it was not an immediate replacement. So it is suggested the amalgamation happened around 1912. An affidavit of 1902 makes it plain that both engines had new boilers and fireboxes in 1902 and 1903, so the puzzle is why there is no evidence of the boiler thus made available (only 10 or 11 years old) being retained as a spare.
By November 1922 Moel Tryfan was out of service, leaving the new WHR very short of locomotives, and the re-purchase of Gowrie was even considered, but rejected.
Sometime after July 1923 Moel Tryfan returned from an overhaul in Boston Lodge and (some say) was taken into Festiniog railway stock, numbered 11 and the cab and boiler mountings reduced to fit the FR loading gauge. She was used from 1924 to 1936 on the WHR and FR between Dinas and Blaenau Ffestiniog. Others argue that she did not enter FR stock until 1934; there are no known photographs of her on the FR.
Entering Boston Lodge for repairs before 1937, she was dismantled and at the start of the preservation era was judged to be beyond repair; she was in a deplorable condition. In October 1954, the boiler and driving bogie were towed across the Cob to Harbour station for scrapping, providing invaluable income for the success of the nascent preservation effort. The trailing bogie survived.
Hindsight allows us to wonder whether the locomotive could possibly have been resurrected. This was not a reasonable proposition in 1954 and those pioneers of preservation should not be unduly criticised for the decision. The loco would have needed a new boiler, a new bogie frame and much else. It can be argued that it would have been quicker and cheaper to build an entirely new locomotive, and that we are better off with a new single Fairlie to the FR design.
As an aside, it is noteworthy that of the four locos in the Old Engine Shed during the closure, only Merddin Emrys has been restored to service - and that was an epic.
Reference: John Keylock + Michael Bishop "Two into One Will Go" Welsh Highland Heritage Group Journal No 46 December 2009