Editing T and O map (section)

===Boundaries, center and orientation===

The ''T'' is the [[Mediterranean]], the [[Nile]], and the [[Don River (Russia)|Don]] (formerly called the Tanais) dividing the three [[continent]]s, [[Asia]], [[Europe]] and [[Africa]], and the ''O'' is the encircling [[ocean]].<ref>Woodward, "Medieval ''Mappaemundi''", 296.</ref> In line with Isidore's description, Asia is normally depicted as equal in size to Africa and Europe combined.<ref>Mauntel, "The T-O Diagram and its Religious Connotations", 59. A small number of T-O maps instead depict Africa as taking up half the circle as opposed to Asia (Woodward, "Medieval ''Mappaemundi''", 343.) and a smaller number still depict Europe in this way (e.g. Ingrid Baumgärtner, "Die Wahrnehmung Jerusalems auf mittelalterlichen Weltkarten", in ''Jerusalem: im Hoch- und Spätmittelalter: Konflikte und Konfliktbewältigung - Vorstellungen und Vergegenwärtigungen'', ed. Dieter R. Bauer, Klaus Herbers and Nikolas Jaspert (Frankfurt am Main: Campus Verlag, 2001), 271-73).</ref> The majority T-O maps are oriented to the east, though examples of north, south and westward orientation can also be found.<ref> Non-eastern orientations are associated above all with T-O maps that accompany [[Bellum Jugurthinum|Sallust's ''Jugurthine War'']], on which see Woodward, "Medieval ''Mappaemundi''", 343-4, where examples of all four orientations are also provided. There is no consensus on the origins of the predominantly eastern orientation, some like Mauntel, "The T-O Diagram and its Religious Connotations", 65-9 argue that it is a specifically Christian development, while others like Patrick Gautier Dalché, "L'héritage antique de la cartographie médiévale: Les problèmes et les acquis", in ''Cartography in Antiquity and the Middle Ages: Fresh Perspectives, New Methods'', ed. Richard J. A. Talbert and Richard W. Unger (Leiden: Brill, 2008), 55-6 are more circumspect about the specifically Christian significance of this orientation.</ref> 

The idea that [[Jerusalem]] was generally represented in the center of the map as the navel of the world, the ''[[umbilicus mundi]]'', is a false generalisation from a relatively small number of very famous 13th-century [[mappa mundi|''mappae mundi'']].<ref>Woodward, "Medieval ''Mappaemundi''", 340 and Baumgärtner, "Die Wahrnehmung Jerusalems", 304.</ref> The earliest T-O maps marked no particular geographic center and while some early ''mappae mundi'' were specifically centered on classical sites like Delos or the Cyclades, most simply had the Mediterranean or Aegean Sea in the middle.<ref> Baumgärtner, "Die Wahrnehmung Jerusalems", 275-94.</ref> It was only after the First Crusade that Jerusalem began to be represented as the center of the world on medieval maps, a trend which rose to prominence from the mid-12th century through the early-14th century, but was never universally observed.<ref>Woodward, "Medieval ''Mappaemundi''", 341-2 and Baumgärtner, "Die Wahrnehmung Jerusalems", 294-310.</ref>

The location of Paradise (the Garden of Eden) in the east of Asia is based upon the [[Septuagint]] translation of Genesis 2:8, which describes the garden of Eden being planted in the east. This is a longstanding feature of Christian textual geographies, and while not present on the earliest T-O maps, it is a prominent feature of many early ''mappae mundi'', especially the [[Beatus map|''Beatus maps'']].<ref>Mauntel, "The T-O Diagram and its Religious Connotations", 67-9.</ref> These depictions are often combined with a depiction of the four rivers of Paradise: the Tigris, Euphrates, Pishon and Gihon, the latter two of which were sometimes understood by medieval cartographers as the Ganges and Nile (or Geon) respectively. These were either depicted as flowing within/out from paradise and/or as four major rivers on the map.<ref>Woodward, "Medieval ''Mappaemundi''", 328.</ref>