Geocart Projections

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Ortelius oval


Geocart menu class: Miscellaneous
Modified pseudocylindrical
Neither conformal nor equal area


Meridians: Central meridian is straight. Other meridians are circular arcs, becoming semicircles between the meridians 90° and 180° from the central meridian. Equally spaced along the Equator but not along other parallels.
Parallels: Straight lines, equally spaced on the central meridian
Poles: Lines half the length of the Equator
Symmetry: Along the central meridian or the Equator


True along the central meridian and the Equator




16th-century whole-world maps


Battista Agnese (1514-64) used the projection in 1544, but the name comes from Abraham Ortelius (1527-98) of Flanders, who used it in 1570.

Similar projections

Often confused with Eckert III, which has elliptic arcs for meridians
Apian Globular I is the same for one hemisphere.
Bordone Oval projection of 1528 has points for poles and near-ellipses or ovals for meridians but is otherwise very similar.

Description adapted from J.P. Snyder and P.M. Voxland, An Album of Map Projections, U.S. Geological Survey Professional Paper 1453. United States Government Printing Office: 1989.