The more one examines this subject the more he is inclined to accept this theory which gets over the difficulty of assuming that the Irish obtained their classical learning from Britain where as Zimmer has shown there was not any classical learning wide and profound enough to produce such results;[48] nor were the High Schools of Gaul a quiet place for learning in the fifth century[49] though Colgan would have us believe—we know not on what authority—that St. Patrick sent St. Olcan to Gaul to study sacred and profane learning so that he might return to Ireland to establish “publicas scholas.”[50] There is nothing improbable in supposing that these rhetoricians should flee to Ireland for safety just as refugee Christians fled to the same island from the persecutions of the Emperor Diocletian more than a century before St. Patrick’s time.[51] Indeed Ireland was well known to Roman geographers, though their ideas of its location were rather inaccurate. Tacitus informs us that Ireland is situated between Spain and Britain,[52] a conception which points to direct communication with the Empire. The same author further informs us that the harbours of Ireland were well known to merchants through trade and commerce.[53] As the researches of Mr. George Coffey and Mrs. Greene have shown, intercourse and commerce between Ireland and Gaul had been constant and regular for centuries before the fifth.[54] There were even Gallic mercenaries in the service of Irish kings during the early centuries of our era.[55] Moreover, Irishmen at this time were familiar figures on the Continent. Amongst these may be mentioned Mansuetus, Bishop of Toul about 350 A.D.[56] There can be little doubt that Sedulius, the great Christian poet, author of _Carmen Pascale_, was an Irishman.[57] Sedulius, sometimes called Sedulius the Elder (to distinguish him from another Sedulius who was at Compostella in the eighth century and still another Sedulius who was at Liège in the ninth), flourished between 423–450 A.D.[58] His work treating of the chief events recorded in the Old and New Testament was “the first Christian Epic worthy of the name.”[59] Dr. Sigerson by a scholarly analysis[60] of the verse structure traces the influence of the Irish school of prosody referred to in the previous chapter. Though Sedulius wrote in Latin and followed the classical forms of verse, yet he infused into them certain characteristics of Irish poetry, such as systematic alliteration, assonance and rhyme—qualities that reveal the Gael.