“We read of Labhraidh Loingseach that his ears were like those of a horse; and hence, he used to kill on the spot everyone who cut his hair, lest he or anyone else might be aware of this blemish. Now he was wont to have his hair cropped every year, that is, to have cut off the part of his hair that grew below his ears. It was necessary to cast lots to determine who should crop the king each year, since it was his wont to put to death everyone who cropped him. Now it happened that the lot fell on the only son of a widow who approached the close of her life, and who lived near the king’s stronghold. And when she heard that the lot had fallen on her son, she came and besought the king not to put her only son to death, seeing he was her sole offspring. The king promised her that he would not put her son to death, provided he kept secret what he should see, and made it known to no one till death. And when the youth had cropped the king, the burden of that secret so oppressed his body that he was obliged to lie in the bed of sickness, and that no medicine availed him. When he had lain long in a wasting condition, a skilful druid came to visit him, and told his mother that the cause of his sickness was the burden of a secret, and that he would not be well till he revealed his secret to some thing; and he directed him, since he was bound not to tell his secret to a person, to go to a place where four roads met, and to turn to his right and to address the first tree he met, and to tell his secret to it. The first tree he met was a large willow, and he disclosed his secret to it. Thereupon the burden of pain that was on his body vanished; and he was healed instantly as he returned to his mother’s house. Soon after this, however, it happened that Craiftine’s harp got broken, and he went to seek the material for a harp, and came upon the very willow to which the widow’s son had revealed the secret, and from it he took the material for his harp and when the harp was made and set to tune, as Craiftine played upon it all who listened imagined that it sang, ‘Da o phill ar Labhraidh Lorc,’ that is, Labraidh Loingseach, meaning, ‘Two horse’s ears on Labhraidh Lorc’; and as often as he played on that harp, it was understood to sing the same thing. And when the king heard this story, he repented of having put so many people to death to conceal that deformity of his, and openly exhibited his ears to the household, and never afterwards concealed them.”

Geoffrey Keating, ‘The History of Ireland’ (Section 30)