The recently elected local MP, Mr Henry Haydn Jones, sought a buyer but failed. He then bought the undertaking himself, for £5500 in 1911, and formed the Abergynolwyn Slate & Slab Co. Ltd. to operate the quarry, and negotiated new leases with the landowners.
There was a brief resurgence in business after the First World War, but sales dropped thereafter and the quarry remained open only by cutting away at the pillars separating the underground chambers, a cheap alternative to opening up new chambers and levels. Relations between Haydn Jones and the quarrymen were occasionally strained, and at times the quarry closed for considerable periods or worked only a three-day week. Haydn Jones’ leases on the quarry land expired in 1941, though he continued with an annual tenancy.
The quarry finally closed following a serious collapse on Boxing Day 1946, the inevitable result of years of “pillaring”. After the remaining slate had been brought down, the quarry lay abandoned for several years before the equipment was scrapped. All the buildings on the site have now been demolished, for safety reasons. Visitors should note that Bryn Eglwys quarry is a potentially dangerous place, in particular in the areas of the 1946 collapse and subsequent rock falls, and extreme care must be exercised at all times. Much of the quarry lies on private land.
There had been no investment in either quarry or railway for many years. On the railway only one locomotive, ‘Dolgoch’, was workable and the track was in a deplorable state, mainly held in place by the grass. Sir Haydn said he would run the railway as long as he lived, but both he and the railway were over 80 years old. Sir Haydn was true to his word and the railway was still running what was by now a summer-only passenger service when he died in July 1950. His widow kept the railway running for the rest of the season but when it closed for the winter in October 1950 it seemed unlikely it would ever run again.