Note 27 — Chapter VII · Triumphs of the Water-world

The late and grotesque story of the Gilla Decair may be mentioned next: he was one of the Fomorach, and had a wonderful kind of horse on whose back most of Finn’s chief warriors were induced to mount. Then the Gilla Decair and his horse hurried towards Corkaguiny, in Kerry, and took to the sea, for he and his horse travelled equally well on sea and land. Thus Finn’s men, unable to dismount, were carried prisoners to an island not named, on which Dermot in quest of them afterwards landed, and from which, after great perils, he made his way to Tír fo Thuinn, ‘Terra sub Unda,’ and brought his friends back to Erin27. Now the number of Finn’s men taken away by force by the Gilla Decair was fifteen, fourteen on the back of his horse and one clutching to the animal’s tail, and the Welsh Triads, i. 93 = ii. 11, seem to re-echo some similar story, but they give the number of persons not as fifteen but just one half, and describe the horse as Du (y) Moroeđ, ‘the Black of (the) Seas,’ steed of Elidyr Mwynfawr, that carried seven human beings and a half from Pen Ỻech Elidyr in the North to Pen Ỻech Elidyr in Môn, ‘Anglesey.’ It is explained that Du carried seven on his back, and that one who swam with his hands on that horse’s crupper was reckoned the half man in this case. Du Moroeđ is in the story of Kulhwch and Olwen called Du March Moro, ‘Black the Steed of Moro,’ the horse ridden in the hunt of Twrch Trwyth by Gwyn ab Nuđ, king of the other world; and he appears as a knight with his name unmistakably rendered into Brun de Morois in the romance of Durmart le Galois, who carries away Arthur’s queen on his horse to his castle in Morois28. Lastly, here also might be mentioned the incident in the story of Peredur or Perceval, which relates how to that knight, when he was in the middle of a forest much distressed for the want of a horse, a lady brought a fine steed as black as a blackberry. He mounted and he found his beast marvellously swift, but on his making straight for a vast river the knight made the sign of the cross, whereupon he was left on the ground, and his horse plunged into the water, which his touch seemed to set ablaze. The horse is interpreted to have been the devil29, and this is a fair specimen of the way in which Celtic paganism is treated by the Grail writers when they feel in the humour to assume an edifying attitude.