Geocart Projections

What is a projection?

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Guyou

Classifications

Geocart menu class: Miscellaneous
Conformal

Graticule

Meridians: Central meridian is straight. The 90th meridians are straight but bent at the 45th parallels N. and S. Other meridians are complex curves.
Parallels: Equator is straight. Other parallels are complex curves. Poles: Points, in the midpoint of opposite sides of a square bounding a hemisphere
Symmetry: About the central meridian or the Equator

Scale

Varies considerably along each meridian and parallel

Distortion

Great distortion of area, especially near the 90th meridian at latitudes 45°N. or S., where conformality fails

Other features

Shows hemisphere conformally in a square and the world in a 2x1 rectangle. Hemispheres can be mosaicked to form a continuous map indefinitely.

Usage

Novelty map of a hemisphere or of the world

Origin

Presented by Emile Guyou of France in 1887

Aspects

A transverse aspect is the Peirce Quincuncial projection. An oblique aspect is the Adams projection of a hemisphere in a square.

Similar projections

Listed under Aspects above

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.