The horse plays a very active part in Welsh fairy tales. Not only does his skeleton serve for Mary Lwyds[53] and the like, but his spirit flits. The Welsh fairies seem very fond of going horseback. An old woman in the Vale of Neath told Mrs. Williams, who told Thomas Keightley, that she had seen fairies to the number of hundreds, mounted on little white horses, not bigger than dogs, and riding four abreast. This was about dusk, and the fairy equestrians passed quite close to her, in fact less than a quarter of a mile away. Another old woman asserted that her father had often seen the fairies riding in the air on little white horses; but he never saw them come to the ground. He heard their music sounding in the air as they galloped by. There is a tradition among the Glamorgan peasantry of a fairy battle fought on the mountain between Merthyr and Aberdare, in which the pigmy combatants were on horseback. There appeared to be two armies, one of which was mounted on milk-white steeds, and the other on horses of jet-black. They rode at each other with the utmost fury, and their swords could be seen flashing in the air like so many penknife blades. The army on the white horses won the day, and drove the black-mounted force from the field. The whole scene then disappeared in a light mist.