Merlin and his mother at the request of the messengers accompanied them from Carmarthen to Snowdon to the presence of King Vortigern; and when the boy was asked who was his father, his mother in reply gave a very peculiar account of the birth of her son, whose father she declared was a supernatural being, and so had no human father. Then the King said to Merlin, "I must have thy blood." And when the youth asked the King what good could his blood be more than the blood of any other man, he was informed in reply that the twelve wise men or bards had suggested the blood of a youth in order to make the building stand. Then Merlin asked the bards or magicians what was the real cause that the building of the tower was not a success? But they could give no answer. Young Merlin now upraided them for their ignorance and the cruelty of their suggestion. He then gave orders to dig the ground, and when this was done a lake was discovered. Merlin drained this lake, and at the bottom, as he had predicted, a stone chest was discovered in which there were two sleeping dragons. These, whenever they awoke, fought with each other, and their violence shook the ground, thus causing "the work to fall." When the King commanded the stone chest to be opened the two dragons came out and began a fierce battle. One of these dragons was white and the other red. At first the white dragon drove the red one to the middle of the pool, then the red one, provoked to rage, drove the white one thither in turn. When the King asked what this should signify, Merlin exclaimed as follows:--"Woe to the red dragon for her calamity draws nigh, and the white dragon shall seize on her cells. By the white dragon the Saxons are signified, and the Britons by the red one, which the white shall overcome. Then shall the mountains be made plains, and the glens and rivers flow with blood. The Saxons shall possess almost all the island from sea to sea, and afterwards our nation shall arise, and bravely drive the Saxons beyond the sea." Nennius, chap. 43. The old King Vortigern then left the neighbourhood of Snowdon, and removed to South Wales, and built a fort or a Castle on a spot known to this day as Craig Gwrtheyrn, or Vortigern's Rock, near Llandyssul and Pencader.