The Barddas of Iolo Morganwg, Vol. I., ed. by J. Williams Ab Ithel, , at sacred-texts.com
a. e. i. o.--b. c. t. l. s. r. p.
It was Einigan the Giant that first understood letters; and he made the principal cuttings, which were eleven, that is, the four vowels, and the seven consonants. And he inscribed on wood the memorial of every object he beheld, every story he heard, and every honour he understood. Others considering the things that Einigan did, concluded that he was a devil, and banished him. Upon this he came to his father's kindred in the Isle of Britain, and exhibited his art, and they adjudged him to be the wisest of the wise, and called him Einigan the Gwyddon, and all, who learned the art of letters, they called Gwyddoniaid, which Gwyddoniaid were the principal sages of the Isle of Britain, before Bards were systematically distinguished in respect of privilege and usage. When Bards and Bardism were arranged, they were required to keep the memorial of the eleven cuttings. After this the art was improved, and sixteen cuttings were obtained, which were called the sixteen letters; subsequently, eighteen, and thence until twenty-four, to which were added the fourteen secondary letters, as they are now seen. This is preserved in the memorial of voice and letters, and the usage of the Bards of the Isle of Britain. The system of eleven is called the system of Einigan; the one of sixteen, the system of Edric; the one of eighteen, the system of Alawn 1 "and the system of the Bards;" 2 the one of twenty-four is called the system of Arthavael; and
p. 54 p. 55
the one now in use is called the new system, and the system of Idnerth the Artist. It was in the time when Gruffudd, son of Llywelyn, son of Seisyllt, exercised prerogative over Cymru universal, that this Idner lived. 1 Thus are shown the origin of letters and the sciences of books in the memorials of the Bards of the Isle of Britain.
53:1 p. 52 The literary achievement of Alawn is thus recorded in the "Englynion y Gorugiau" by Geraint the Blue Bard;--
The achievement of Alawn, the Bard of Britain,
Was to establish true memorial of spreading fame--
The mutual recording in the art of disputation.
Iolo MSS. pp. 263, 670.
53:2 p. 53 Added from another MS.
55:1 p. 54 I.e. between A. D. 1021 and 1064.