This section is from the book "Ancient Legends, Mystic Charms, And Superstitions Of Ireland", by Jane Francesca Wilde. Also available from Amazon: Ancient Legends, Mystic Charms, And Superstitions Of Ireland.
There is a place on the shore of Scattery Island, where, according to the most ancient tradition, a sacred well once existed, with miraculous curative powers. But no one could ever discover the place, for at high water the sea covered every point up to the edge of the land, and the shifting sand made all efforts to find the locality of the well vain and fruitless.
But one day a young man who was lame in both legs from the effects of a fall, and much disabled in consequence, was going along the shore with some companions, when he suddenly sank up to his waist in the sand. With much difficulty, and after a long while, his comrades managed to haul him up, when to their amazement they found that his legs were now quite straight, and he stood up before them four inches taller than before he sank down into the sand.
So at once they knew that the sacred well must have worked the cure, and they dug and dug and cleared away the sand, till at last they came on some ancient steps, and down below lay the well, clear and fresh, and untouched by the salt of the sea, the holy well of St. Seenan, that their fathers and forefathers had vainly looked for.
Now there was great rejoicing in the country when the news spread ; and all the people from far and near who had pains and ailments rushed off to the well and drank of the waters and poured libations of it over their persons, wherever the pain or the disease lay, and in a short time wonderful cures were effected. So next day still greater crowds arrived to try their good luck. But when they came to the place, not a vestige of the well could be found. The sand and the sea had covered all, and from that day to this the holy well of St. Seenan has never been seen by mortal eyes.