The medieval Mappa Mundi in England's Hereford cathedral, for example, is little more than drawings on vellum, or stretched calfskin, and it lacks Ptolemy's geometric method.

比如，中世纪制作英兰赫里福德教堂世界地图过是些绘在羔皮、或者说拉犊皮上图案，没有使用托勒密几何方法。