Not to that demon's son, whom Arthur erst, For necromancy, at Caerleon, first Graced greatly, Merlin,--not to him alone Did those lost learnings of white magic, known As sorcery and witchcraft, then belong. Taliesin, now, hath told us in a song Of one at Arvon, Math of Gwynedd; lord Of some vague cantrevs of the North; whose sword Beat back and slew a southern king, through wrath And puissance of Gwydion, whose path Thence on, with love, he honored. Now this Math Was learned in wondrous witchcraft: as he willed, He wrought the invisible visible, and filled The sight with seeming shapes, which it believed Realities, nor knew it was deceived. For, at his word, the winds were wan with tents, And armies rose of airy elements; And brassy blasts of war from bugles brayed, And armored hosts in battle clanged and swayed, And at a word were not. And at his nod, Steeds, rich-accoutered, whinnying softly, trod The dædal earth; and hounds, of greater worth, And wirier, too, than dogs of mortal birth, Rose up, like forest fungus, from the earth Around th' astonished stag, or flying doe, Let Math but wish it or his trumpet blow. But only things that had their counterpart On earth could he make real through his art. Now, to his castle, Math, through Gwydion,-- The son of Don,--the daughter dark of Don, The silver-circled Arianrod, had brought; A southern rose of beauty, whom Math thought To wed, in love and friendship, without blame, And at Caer Dathyl. When the maiden came Said Math, "Art thou a virgin?"--Like a flame Mantling, her answer angered, "Verily, I know not other, lord, than that I be!"-- So wrought he then through magic that the form Of her boy baby seemed upon her arm, White as a rose. "A Mary!--Yea!" laughed Math; "Forsooth, another Mary!" then in wrath Laid harsh hands on the babe and fiercely flung Far in the salt sea. But the strong winds clung Fast to the Elfin and the lithe waves swept Him safely shoreward dry; some fishers kept Him thus unseaed and christened Dylan, fair Son of the wave, and fostered him with care. Nor was this really hers. But Gwydion, Brother to Arianrod, before the sun Had time to glimpse it with one golden glaive, Swiftly,--as hoping the real babe to save,-- Some dim small body on the castle pave In raven velvet seized; and, hiding, he Stole this from court, to subtly raise to be A comely youth. In time, to Arianrod Came, swearing by the rood and blood of God He brought her back her son.