Monastic cartography did not keep pace with theory. The disputed habitable land beyond the confines of the known world, and separated from it by the impassable torrid zone (a classical conception), appeared in maps of the seventh and eighth centuries. Apart from this (and it came to be generally admitted) we have rectangular oblong maps like that of Cosmas, and circular maps, out of which was evolved the diagrammatic form of a =T= within an =O=, where the =T= represented the Mediterranean, the Tanais, and the Nile, its upright showing the westward extension of the sea, and the cross-stroke the two rivers, to left and right respectively, so that the west was at the bottom of the map. Europe lay within the left-hand angle of the =T=, Africa in the right-hand angle; Asia was the half circle above it. The holy city of Jerusalem lay “in the midst of the nations.” Some maps, again, gave the earth an oval form. In all, the habitable earth was still surrounded by ocean. In the far east sometimes appeared Paradise. This feature and the unknown habitable world above mentioned were both shown in the map of Beatus, a Spanish priest (_c._ 730–798), who illustrated his _Commentaria in Apocalypsin_ with one of the earliest known Christian maps of the world, several copies of which, dating from the tenth to the thirteenth centuries, are preserved. In this map the “known” habitable world appears as a dome-shaped mass with its flat base to the south, forming the northern shore of a strait separating it from the unknown southern land. The known world is broken for more than half its breadth by the vast gulf of the Mediterranean, which has two great arms reaching far northward; the Caspian Sea is a gulf opening into the north-east part of the circumfluent ocean, in which are set islands in an orderly ring all round the world; all sense of direction in the flow of rivers is awry, and topographical accuracy is, of course, entirely wanting.