Directory of Map Projections

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transverse plate carrée

Cassini-Soldner

Cassini

Aspects of: plate carrée

Classifications

cylindric
equidistant

Graticule

Central meridian, each meridian 90° from central meridian, and the equator are straight lines. Other meridians and parallels are complex curves, concave toward the central meridian and the nearest pole, respectively.
Poles: Points along the central meridian.
Symmetry: About any straight meridian or the equator.

Scale

True along the central meridian and along any straight line perpendicular to the central meridian.
Increases with distance from the central meridian, along a direction parallel to the central meridian.

Distortion

Function of the distance from the central meridian. No distortion occurs along the central meridian, but there is both area and local shape distortion elsewhere.

Other features

Conceptually projected onto a cylinder tangent to the globe at the central meridian.
Can be compressed north-south to provide a transverse equirectangular projection, but rarely done.

Usage

Topographic mapping (ellipsoidal form) of British Isles before the 1920s; replaced by the transverse Mercator.
Topographic mapping of a few countries currently.

Origin

Developed by César François Cassini de Thury (1714-1784) for topographic mapping of France in the middle 18th century.

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.