IRISH, the Celtic language of Ireland (q.v.), also called Erse. Old Irish (700—I I 00) contains a wealth of inflectional forms in declension and conjugation. Many of the forms, however, dis appeared early. An interesting rule of vocalic harmony (slender to slender and broad to broad) is recorded. In Irish final syllables in general disappear except long vowels followed by s or r and u/o preceded by i. There were difficulties due to the insuffi ciency of symbols, and it is possible that popular speech moved rapidly ahead of the written language in phonetic developments. In Middle Irish the declensions and conjugations were much simplified. The neuter gender disappeared. In several respects the verbal system is developed as compared with the old Irish forms, details of which are given in standard grammars. Dia
lectical variations must have existed from early times, and while Leinster Irish has disappeared, there are still peculiarities dis tinguishing the Irish of Munster, Connaught and Ulster, the south being more conservative than the north. In the early period a number of loan words appear from Latin connected with the church or with articles of civilization. There are some of Norse origin. In the Middle Irish periods many French words were accepted. English has now provided a large number of words but the revival of Irish under the new political conditions should lead to further developments.
See J. Vendryes, Grammaire du vieil-irlandais (1908) ; R. Thur neysen, Handbuch des Alt-Irischen (1909), also Revue Celtique and Zezltschrift fur keltische Philologie.