The assiduous attempt to diffuse religious doctrines paved the way, at one time, for warlike undertakings, at another for the spread of peaceful ideas and commercial intercourse. The zeal which is so peculiar to the religions systems of India, Palestine, and Arabia, and which is altogether free from the indifference of Grecian and Roman polytheism, kept alive the study of geography in the first half of the Middle Ages. Letronne, the commentator of the Irish monk Dicuil, has proved, in an acute way, that after the Irish missionaries were driven out of the Färöe Islands by the Normans, they began to visit Iceland about the year 795. The Normans, when they came to Iceland, found there Irish books, bells for ringing for mass, and other objects, which former strangers, who were called Papar, had left behind. These Papæ (fathers) were the Clerici of Dicuil. Now if, as we must suppose from his testimony, those objects belonged to the Irish monks, who came from the Färöe Islands, the question is, why are the monks (Papar) called in their native traditions "Westmen"--men who have come from the west over the sea? Respecting the connection of Prince Madoc's voyage to a great western country in 1170, with the "Great Ireland" of the Iceland traditions, all accounts are enveloped in deep obscurity. Compare the inquiries in _Rafn Antiq. Amer._, p. 203, 206, 446, 451; and Wilhelmi upon Iceland, _Hvitramannaland_, the Land of White Men, p. 75, 81; Letronne, _Récherches Géog. et Crit. sur le Livre de Mensurâ Orbis Terræ, composé en Irelande par Dicuil_, 1814, p. 129, 146.