Scholastic ogham

Use of the early medieval Irish ogham alphabet is largely divided between "monumental" epigraphy and "scholastic" use in, or influenced by, manuscript tradition,

Scholastic ogham notably involves artificial expansions of the alphabet, such as the forfeda group, and many variations or cryptographic substitutions for the classic ogham alphabet. Scholastic ogham develops from about the 7th century and remains in use for notes in manuscripts until the 16th century.

Manuscript tradition of ogham notably records Bríatharogam, i.e. medieval kennings of letter names. The most notable source of such kennings is In Lebor Ogaim, preserved in a late 14th-century manuscript.

Even after it ceased to be used as an everyday alphabet for writing, ogham continued to be used as the basis for teaching grammar and the rules and metrics of poetry in the Gaelic language. The medieval work The Scholar's Primer or Auraicept na n-Éces, laid down the basis for poetic composition in the Irish language for the trainee poet or file, and looked to ogham or more exactly the Beith-luis-nin for guidance. This was because the ogham alphabet was felt to be peculiarly suited to the needs of the Irish language.

In addition the training of the poet or file, involved the learning of one hundred and fifty varieties of ogham – fifty in each of the first three years of study. It is clear that most of these are the same as the one hundred or so different ogham alphabets found in The Ogam Tract or In Lebor Ogaim, which was included along with the Auraicept in the Book of Ballymote. Most of these alphabets are cryptic varieties of doubtful practical value, but some were word lists which could have given the poet a convenient vocabulary at his fingertips, while others indicate a link to tally or counting systems. Perhaps their main value was simply to train the mind in the use of words and concepts, as word play and 'punning' were a major part of Gaelic poetry.

So central was ogham to Gaelic learning that until modern times the Latin alphabet was taught in both Irish and Scots Gaelic using the letter names borrowed from the Beith-luis-nin, along with the tradition that each name was that of a different tree. The following is the list from Dinneen's Irish–English Dictionary, published in 1927 A: Ailm (Elm); B: Beith (Birch); C: Coll (Hazel); D: Dair (Oak); E: Eadadh (Aspen); F: Fearn (Alder); G: Gath/Gort (Ivy); H: hUath (Whitethorn); I: Íodha (Yew), L: Luis (Rowan); M: Muin (Vine); N: Nuin (Ash); O: Oir (Broom); P: Peith (Dwarf Elder); R: Ruis (Elder); S: Sail (Willow); T: Teithne (Furze); U: Ur (Heather).

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