We might expect to find that direct influence, as a general rule, can be most easily traced in the case of religious themes. Here, in the literature of vision, so popular in Ireland, a chord was struck which continued to vibrate powerfully until the time of the Reformation. In this branch the riotous fancy of the Celtic monk caught the medieval imagination from an early period. Bede has preserved for us the story of Fursey, an Irish hermit who died in France, A.D. 650. The greatest Irish composition of this class with which we are acquainted, the _Vision of Adamnan_, does not appear to have been known outside the island, but a later work of a similar nature met with striking success. This was the _Vision of Tundale_ (Tnudgal), written in Latin by an Irishman named Marcus at Regensburg, about the middle of the twelfth century. It seems probable that this work was known to Dante, and, in addition to the numerous continental versions, there is a rendering of the story into Middle English verse. Closely allied to the Visions are the _Imrama_ or "voyages" (Lat. _navigationes_). The earliest romances of this class are secular, _e.g., Imram Maelduin_, which provided Tennyson with the frame-work of his well-known poem. However, the notorious love of adventure on the part of the Irish monks inevitably led to the composition of religious romances of a similar kind. The most famous story of this description, the_ Voyage of St. Brendan_, found its way into every Christian country in Europe, and consequently figures in the South English Legendary, a collection of versified lives of saints made in the neighborhood of Gloucester towards the end of the thirteenth century. The episode of St. Brendan and the whale, moreover, was probably the ultimate source of one of Milton's best known similes in his description of Satan. Equally popular was the visit of Sir Owayn to the Purgatory of St. Patrick, which is also included in the same Middle English Legendary. Ireland further contributed in some measure to the common stock of medieval stories which were used as illustrations by the preachers and in works of an edifying character.