The next MS. is as curious—the _Cathach_, or _Book of Battles_—a copy of the Psalms, supposed to have been written by S. Columba. It consists of fifty‐eight leaves of vellum, and appears to be perfect from the xxxist to the cvith Psalm, all prior to which are gone, and is enclosed in a handsome shrine. Why it was called the _Book of Battles_ is told by O’Curry, from the _Life of S. Columba_, by Magnus O’Dohmnaill. S. Columba, when on a visit to S. Finnen of Drom Finn, being very anxious to have a copy of S. Finnen’s Book of the Psalms, made one surreptitiously by borrowing the book, and copying it in the church after every one else had left. S. Finnen had notice of this underhand proceeding of his brother saint from one of his pupils, and accordingly, as soon as the copy was finished, demanded possession of it. S. Columba refusing to comply with this demand, the matter was referred to Diarmaid Mac Ferghusa Cerrbheaill, King of Erinn, who pronounced against him in a judgment which to this day remains a proverb in Ireland—_Le gach bóin a boinin_ (“To every cow its calf”), and so, by analogy, “to every book its copy.” This adverse judgment, closely followed by the accidental death of the son of Diarmaid’s chief steward while engaged in a game of hurling with the son of the King of Connaught—at that time a hostage at Tara—who was torn from S. Columba’s arms, into which he had thrown himself for sanctuary, and put to death, so enraged the saint that he stirred up his relatives in Tirconnel and Tyrone to revenge the insult, and a bloody battle was fought in Connaught, which ended in the rout of the king’s army: and this was how the book obtained its name. For thirteen hundred years the book was preserved as an heirloom by the O’Donnells, having been handed down by S. Columba himself, who belonged to that clan. It is now preserved in the Royal Irish Academy. Four pages have been selected for copying, containing severally the first twelve verses of Psalm lxxx., the last three of lxxxix., and the first seven of xc., the whole of xciv., and the first eleven of xcv. The condition in which these pages remain is wonderful, and reflects great honor upon the family who have for so many ages and through so many national troubles and disturbances preserved this relic with sacred care.