The Barddas of Iolo Morganwg, Vol. I., ed. by J. Williams Ab Ithel, , at sacred-texts.com
The three materials of language and speech: letter; syllable; and word.
The three materials of speech: word; sense; and sentence.
There are twenty primitive letters, thirteen of which are called consonants; and from them seven secondaries are derived; and seven of the primitives are called vowels, but others call them scunds.