The story of their wanderings through the world is itself a geographical description of the ancient world, based in detail on the geographical chapters of Orosius. Of this story also there are two distinct versions. In one they travel overland through the continent of Europe, passing through the various peoples and territories named by Orosius. It was on this journey that they fell in with the Picts, for whom also a close scrutiny of Virgil provided two distinct origins, as already told. In the other account they sailed round the world, and the names of the various places they touched or passed in the narrative are also taken from the geography of Orosius. A noteworthy feature of that geography is that it is based on the early writings of Eratosthenes and Strabo and entirely ignores the much larger and more accurate knowledge recorded by Ptolemy in the second century. For example, according to Orosius, the Caspian Sea opens by a strait directly into the northern ocean, and the river Ganges flows into the eastern ocean on the eastern side of Asia. Accordingly we find in the Irish story that our ancestors sailed right out of the Caspian into the northern ocean, then turning eastward came round by the eastern coast of Asia, and passed on that coast the outlet of the Ganges. This view of the world's geography continued to be taught in the Irish schools for centuries. It may be remarked here that the rotundity of the earth was also the common teaching of these schools. It is still more curious to note how the wording of Orosius has supplied some remarkable details in the Irish story. It will be remembered how Bregon, chief of the Gaels in Spain, built a tower on the northern Spanish coast, the Tower of Bregon, and how, one fine evening in spring, his grandson went up to the top of this tower and from it descried the land of Ireland. When the Gaels afterwards took ship and came to Ireland, the place where they landed was Inbhear Scéine. All this comes from the actual phraseology of Orosius.