Now it happened that on one very hot day the daughter of Mananan went down to bathe in the waters of the Boyne, and Ethne and her other maidens along with her. After they had refreshed themselves in the cool, amber-coloured water, they arrayed themselves in their silken robes and trooped back to the Brugh again; but ere they entered it, they discovered that Ethne was not among them.
So they went back, scattering themselves along the bank and searching in every quiet pool of the river and in every dark recess among the great trees that bordered it, for Ethne was dearly loved by all of them; but neither trace nor tidings of her could they find, and they went sorrowfully home without her, to tell the tale to Angus and to her father.
What had befallen Ethne was this. In taking off her garments by the riverside she had mislaid her fairy charm, and was become as a mortal maid. Nothing could she now see of her companions, and all around was strange to her. The fairy track that had led to the riverside was overgrown with briars, the palace of Angus was but a wooded hill. She knew not where she was, and pierced with sudden terror she fled wildly away, seeking for the familiar places that she had known in the fairy life, but which were now behind the Veil. At length she came to a high wall wherein was a wicket gate, and through it she saw a garden full of sweet herbs and flowers, which surrounded a steep-roofed building of stone. In the garden she saw a man in a long brown robe tied about his waist with a cord. He smiled at her and beckoned her to come in without fear. He was a monk of the holy Patrick, and the house was a convent church.
When the monk had heard her tale, he marvelled greatly and brought her to St Patrick himself, who instructed her in the Faith, and she believed and was baptized.
But not long thereafter, as she was praying in the church by the Boyne, the sky darkened and she heard a sound without like the rushing of a great wind, and mingled in it were cries and lamentations, and her own name called again and again in a multitude of voices, thin and faint as the crying of curlews upon the moor. She sprang up and gazed around, calling in return, but nothing could she see, and at last the storm of cries died away, and everything was still again around the church except the singing voice of Boyne and the humming of the garden bees.
Then Ethne sank down swooning, and the monks bore her out into the air, and it was long until her heart beat and her eyes unclosed again. In that hour she fell into a sickness from which she never recovered. In no long time she died with her head upon the breast of the holy Patrick, and she was buried in the church where she had first been received by the monk; and the church was called Killethne, or the Church of Ethne, from that day forward until now.