“Petroleum, rock oil, or what the Welsh call it, Ymenin tylwyth têg, or Fairies’ butter, has been found in the lime stone strata in our mineral country. It is a greasy substance, of an agreeable smell, and, I suppose, ascribed to the benign part of those imaginary beings. It is esteemed serviceable in rheumatic cases, rubbed on the parts affected. It retains a place in our dispensary.”
Pennant’s Whiteford, p. 131.
Bwyd Ellyllon, or Goblins’ Food.
This was a kind of fungus or mushroom. The word is given in Dr. Owen Pughe’s dictionary under the head Ellyll.
Menyg y Tylwyth Têg, Or Fairy Gloves.
The Fox Glove is so called, but in Dr. Owen Pughe’s dictionary, under the head Ellyll, the Fox Glove is called Menyg Ellyllon.
Yr Ellyll Dân, or Goblin Fire.
The Rev. T. H. Evans, in his History of the Parish of Llanwddyn, states that in that parish “Will of the Wisp” is called “Yr Ellyll Dân.” This is indeed the common name for the Ignis fatuus in most, if not in all parts of Wales, but in some places where English is spoken it is better known by the English term, “Jack o’ Lantern,” or “Jack y Lantern.”
Rhaffau’r Tylwyth Têg, or the Ropes of the Fairies.
Professor Rhys, in his Welsh Fairy Tales—Y Cymmrodor vol. v., p. 75—says, that gossamer, which is generally called in North Wales edafedd gwawn, or gwawn yarn, used to be called, according to an informant, Rhaffau’r Tylwyth Têg, that is to say, the Ropes of the Fair Family, thus associating the Fairies with marshy, or rushy, places, or with ferns and heather as their dwelling places. It was supposed that if a man lay down to sleep in such places the Fairies would come and bind him with their ropes, and cover him with a gossamer sheet, which would make him invisible, and incapable of moving.