The Magical Welsh White Cow:

"Llyn Barfog is the scene of the famous elfin cow's descent upon earth, from among the droves of the Gwragedd Annwn. This is the legend of the origin of the Welsh black cattle, as related to me in Carmarthenshire:

           In times of old there was a band of elfin ladies who used to haunt the neighbourhood of Llyn Barfog, a lake among the hills just back of Aberdovey.   It was their habit to make their appearance at dusk clad all in green, accompanied by their milk-white hounds. Besides their hounds, the green ladies of Llyn Barfog were peculiar in the possession of droves of beautiful milk-white kine, called Gwartheg y Llyn, or kine of the lake. One day an old farmer, who lived near Dyssyrnant, had the good luck to catch one of these mystic cows, which had fallen in love with the cattle of his herd. From that day the farmer's fortune was made. Such calves, such milk, such butter and cheese, as came from the milk-white cow never had been seen in Wales before, nor ever will be seen again. The fame of the Fuwch Gyfeiliorn (which was what they called the cow) spread through the country round.

The farmer, who had been poor, became rich; the owner of vast herds, like the patriarchs of old. But one day he took it into his silly noddle that the elfin cow was getting old, and that he had better fatten her for the market. His nefarious purpose thrived amazingly. Never, since beef steaks were invented, was seen such a fat cow as this cow grew to be. Killing day came, and the neighbours arrived from all about to witness the taking-off of this monstrously fat beast. The farmer had already counted up the gains from the sale of her, and the butcher had bared his red right arm. The cow was tethered, regardless of her mournful lowing and her pleading eyes ; the butcher raised his bludgeon and struck fair and hard between the eyes; when lo ! a shriek resounded through the air, awakening the echoes of the hills, as the butcher's bludgeon went through the goblin head of the elfin cow, and knocked over nine adjoining men, while the butcher himself went frantically whirling around trying to catch hold of something permanent. Then the astonished assemblage beheld a green lady standing on a crag high up over the lake, and crying with a loud voice:

Dere di felen Emion,
Cyrn Cyfeiliorn-braith y Llyn,
A'r foci Dodin,
Codwch, dewch adre.

Come yellow Anvil, stray horns,
Speckled one of the lake,
And of the hornless Dodlin,
Arise, come home.

          Whereupon not only did the elfin cow arise and go home, but all her progeny to the third and fourth generations went home with her, disappearing in the air over the hill tops and returning nevermore. Only one cow remained of all the farmer's herds, and she had turned from milky white to raven black. Whereupon the farmer in despair drowned himself in the lake of the green ladies, and the black cow became the progenitor of the existing race of Welsh black cattle." Source:  Sacred Texts

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This legend appears, in a slightly different form, in the 'Iola MSS.,' as translated by Taliesin Williams, of Merthyr : [Llandovery, published for the Welsh MSS. Society, 1848.]

          'The milk-white milch cow gave enough of milk to every one who desired it; and however frequently milked, or by whatever number of persons, she was never found deficient. All persons who drank of her milk were healed of every illness ; from fools they became wise ; and from being wicked, became happy. This cow went round the world; and wherever she appeared, she filled with milk all the vessels that could be found, leaving calves behind her for all the wise and happy. It was from her that all the milch cows in the world were obtained. After traversing through the island of Britain, for the benefit and blessing of country and kindred, she reached the Vale of Towy; where, tempted by her fine appearance and superior condition, the natives sought to kill and eat her; but just as they were proceeding to effect their purpose, she vanished from between their hands, and was never seen again. A house still remains in the locality, called Y Fuwch Laethwen Lefrith (The Milk-white Milch Cow.)'  "

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