high-water mark of the power of the Eoghanacht kings of Munster. After 500 years of undisputed sovereignty in Munster, the Eoghanacht dynasty of Cashel reached a turning point in the battle of Belach Mugna in 908. In that year, urged on by Flaithbertach, abbot of Inis Cathaigh, an eligible prince and afterwards king of Cashel, king Cormac, the bishop, invaded Leinster. The high-kings of the line of Niall regarded the Leinster kings as their own choice vassals and jealously reserved to themselves the privilege of exacting homage and tribute from Leinster. We have seen how a high-king allowed a king of Cashel to plunder and harry in Connacht and Meath, and interfered with effect only when the Assembly of Carman and the sovereignty of Leinster were involved. So it befel with Cormac. Advancing through Ossory he compelled the king of Ossory to join forces with him, and crossing the Barrow they were confronted by the Leinster king and his army. They encamped for the night, prepared to do battle on the morrow. Flann Sinna, the high-king, must have been well warned, for when the morning came, the Munster army found not only the Leinstermen against them in front, but the high-king and the king of Connacht coming upon their left flank. The king of Ossory attempted to retreat but was cut off and killed. The battle became a rout. King Cormac was unhorsed and beheaded. Two Munster abbots fell in the slaughter. The abbot of Inis Cathaigh escaped. A graphic account of this expedition, with all the appearance of authentic detail, is found in a book of annals apparently compiled at Durrow in Ossory. The memory of King Cormac was held afterwards in great veneration. To him is ascribed the compilation of the Irish glossary that bears his name, also of the Psalter of Cashel and the Book of Rights. The Psalter of Cashel survives only in excerpts and quotations, and to judge from these it was a collection of historical and genealogical matter. Of the Book of Rights, Professor Ridgeway once said to me that it was the most remarkable state document produced by any European country outside of the Byzantine empire in that age. We must consider its character and content on a later occasion. This tragic battle, fought in the year 908, ended the long-established prestige of the Cashel dynasty. Six years afterwards, in 914, the Norsemen took possession of Waterford without opposition; and still six years later, in 920, they took possession of Limerick. Until these years, they had gained no foothold on the land of Munster. Another result of the weakening of the Eoghanacht power was the rapid rise of the Dalcassian kings.