Īrān

"As has been shown above, the Land of Īrān is situated in the central part of the habitable world, but more on the western quarter, so that in longitude most of it lies west of the central meridian (in longitude 90°), while the lesser part falls beyond and to the east of this central line.[…]In the description of the habitable world the positions of places are all reckoned from the equator, this being the topmost line, and (in the map of Īrān, therefore) whatsoever has been set down is after this wise from the tables (of latitudes and longitudes) of places that are commonly agreed to as being (towns) of importance."