NIGHTBRINGER | The Arthurian Encyclopedia

Three Great Exploits of the Island of Britain

The ship of Nevydd Nav Neivion, which carried in it a male and female of all things living, when the Lake of floods burst forth; and the horned oxen of Hu the Mighty, which drew the Avanc of the Lake to land, so that the Lake burst forth no more; and the stones of Gwyddon Ganhebon, on which were read all the arts and sciences of the world.

Red Book of Hergest | C. 1425
Text of the Mabinogion and Other Welsh Tales | John Rhys, 1887