The historical use of these genealogies is very great, not only because they give an authentic pedigree and approximate data for chronological calculation, but from the immense amount of correlative information which they contain.  Every free-born man of the tribe was entitled by blood, should it come to his turn, to succeed to the chieftaincy:  hence the exactitude with which each pedigree was kept; hence their importance in the estimation of each individual; hence the incidental matter they contain, by the mention of such historical events[78] as may have acted on different tribes and families, by which they lost their inheritance or independence, and consequently their claim, however remote, to the chieftaincy.

The ancient history of a people should always be studied with care and candour by those who, as a matter of interest or duty, wish to understand their social state, and the government best suited to that state.  Many of the poorest families in Ireland are descendants of its ancient chiefs.  The old habit—­the habit which deepened and intensified itself during centuries—­cannot be eradicated, though it may be ridiculed, and the peasant will still boast of his “blood;” it is all that he has left to him of the proud inheritance of his ancestors.

The second source of historical information may be found in the HISTORIC TALES.  The reciting of historic tales was one of the principal duties of the Ollamh, and he was bound to preserve the truth of history “pure and unbroken to succeeding generations.”

“According to several of the most ancient authorities, the Ollamh, or perfect Doctor, was bound to have (for recital at the public feasts and assemblies) at least Seven Fifties of these Historic narratives; and there appear to have been various degrees in the ranks of the poets, as they progressed in education towards the final degree, each of which was bound to be supplied with at least a certain number.  Thus the Anroth, next in rank to an Ollamh should have half the number of an Ollamh; the Cli, one-third the number, according to some authorities, and eighty according to others; and so on down to the Fochlog, who should have thirty; and the Driseg (the lowest of all), who should have twenty of these tales."[79]

The Ollamhs, like the druids or learned men of other nations, were in the habit of teaching the facts of history to their pupils in verse,[80] probably that they might be more easily remembered.  A few of these tales have been published lately, such as the Battle of Magh Rath, the Battle of Muighe Leana, and the Tochmarc Momera.  Besides the tales of Battles (Catha), there are the tales of Longasa, or Voyages; the tales of Toghla, or Destructions; of Slaughters, of Sieges, of Tragedies, of Voyages, and, not least memorable, of the Tana, or Cattle Spoils, and the Tochmarca, or Courtships.  It should be remembered that numbers of these tales are in existence, offering historical materials of the highest value.  The Books of Laws demand a special and more detailed notice, as well as the Historical Monuments.  With a brief mention of the Imaginative Tales and Poems, we must conclude this portion of our subject.