In the perusal of the Irish literature, we see that the strength of this conservative instinct has been of the greatest service in the preservation of the early monuments in their purity. So much is this the case, that in many tales the most flagrant contradictions appear, the author or scribe being unwilling to depart at all from that which he found handed down. For instance, in the "Great Breach of Murthemney," we find Laeg at one moment killed, and in the next riding black Shanglan off the field. From this conservatism and careful following of authority, and the littera scripta, or word once spoken, I conclude that the distance in time between the prose tale and the metrical originals was very great, and, unless under such exceptional circumstances as the revolution caused by the introduction of Christianity, could not have been brought about within hundreds of years. Moreover, this same conservatism would have caused the tales concerning heroes to grow very slowly once they were actually formed. All the noteworthy events of the hero`s life and his characteristics must have formed the original of the tales concerning him, which would have been composed during his life, or not long after his death.