Of these only three in Latin are now known to exist, whilst of the great number of Irish poems attributed to him only a few--half a dozen at the most--are likely to be even partly genuine. His best known hymn is the "Altus," so called from its opening word; it was first printed by Colgan,[21] and its genuineness is generally admitted. It is a long and rudely-constructed poem, of twenty-two stanzas, preserved in the Book of Hymns, a MS. probably of the eleventh century. Each stanza consists of six lines,[22] and each line of sixteen syllables. There is a pause after the eighth syllable, and a kind of rhyme between every two lines. The first verses run thus with an utter disregard of quantity. "Altus prosător, vetustus dierum et ingenitus, Erat absque origine primordii et crepidine, Est et erit in sæcula sæculorum infinitus, Cui est unigenitus Christus et Spiritus Sanctus," etc. The second Latin hymn is a supplement to this one, composed in praise of the Trinity, because Pope Gregory who, as the legend states, perceived the angels listening when the "Altus" was recited to him, was yet of opinion that the first stanza of the original poem, despite its additional line, was insufficient to express a competent laudation of the mystery, consequently Columcille added, it was said, fifteen rude-rhyming couplets of the same character as the "Altus," but it is very doubtful whether they are genuine. The third hymn, the "Noli Pater," is still shorter, consisting of only seven rhyming couplets with sixteen syllables in each line. It was in ancient times considered an efficient safeguard against fire and lightning. Some of his reputed Irish poems we have already glanced at; three that Colgan considered genuine were printed by Dr. Reeves in his "Adamnan;" and another, the touching "Farewell to Ara," is contained in the "Gaelic Miscellany" of 1808; and another on his escape from King Diarmuid, when the king of Connacht's son was put to death for violating the Féis at Tara, is printed in the "Miscellany" of the Irish Archæological Society.[23] There are three verses, composed by him as a prayer at the battle of Cooldrevna, ascribed to him in the "Chronicon Scotorum;" and there is a collection of fifteen poems attributed to him in the O'Clery MSS. at Brussels, and nearly a hundred more--mostly evident forgeries--in the Bodleian at Oxford.[24] He does not seem to have ever written any work in prose.