Of these numberless and nameless subjects of Gwyn, some dwell beneath the earth or under the surface of lakes—which seem to take, in Wales, the place of the Gaelic “fairy hills”—and others in Avilion, a mysterious western isle of all delights lying on or just beneath the sea. Pembrokeshire—the ancient Dyfed—has kept the tradition most completely. The story goes that there is a certain square yard in the hundred of Cemmes in that county which holds the secret of the fairy realm. If a man happens to set his feet on it by chance, his eyes are opened, and he can see that which is hidden from other men—the fairy country and commonwealth,—but, the moment he moves from the enchanted spot, he loses the vision, and he can never find the same place again.[556] That country is upon the sea, and not far from shore; like the Irish paradise of which it is the counterpart, it may sometimes be sighted by sailors. The “Green Meadows of Enchantment” are still an article of faith among Pembrokeshire and Caermarthenshire sailors, and evidently not without some reason. In 1896 a correspondent of the _Pembroke County Guardian_ sent in a report made to him by a certain Captain John Evans to the effect that, one summer morning, while trending up the Channel, and passing Gresholm Island (the scene of the entertaining of Brân’s head), in what he had always known as deep water, he was surprised to see to windward of him a large tract of land covered with a beautiful green meadow. It was not, however, above water, but two or three feet below it, so that the grass waved or swam about as the ripple floated over it, in a way that made one who watched it feel drowsy. Captain Evans had often heard of the tradition of the fairy island from old people, but admitted that he had never hoped to see it with his own eyes.[557] As with the “Hounds of Annwn” one may suspect a quite natural explanation. Mirage is at once common enough and rare enough on our coasts to give rise to such a legend, and it must have been some such phenomenon as the “Fata Morgana” of Sicily which has made sober men swear so confidently to ocular evidence of the Celtic Paradise, whether seen from the farthest western coasts of Gaelic Ireland or Scotland, or of British Wales. ----- Footnote 522: See, for example, a folk-tale, pp. 117-123 in Rhys’s _Celtic Folklore_. Footnote 523: Stephens’s Preliminary Dissertation to his translation of Aneurin’s _Gododin_. Footnote 524: _Iolo MSS._, p. 471. Footnote 525: _Iolo MSS._, pp. 597-600. Footnote 526: _Historia Britonum_, Books IX, X, and chaps. I and II of XI. Footnote 527: _Historia Britonum_, Book XI, chap. II. Footnote 528: _Ibid._, Book IX, chap. IX. Footnote 529: _Ibid._, Book IX, chap. _XII_. They appear also as Guanius, King of the Huns, and Melga, King of the Picts, in Book V, chap. XVI. Footnote 530: _Historia Britonum_, Book III, chap. XIX. Footnote 531: _Ibid._, Book III, chap. XX. Footnote 532: