Arago: Exhibits

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Compromise Projections Cont’d

The Globular projection is very old and popular. It is easy to construct and gives an excellent appearance for a hemisphere; but it is not used for full world maps.

The idea of wrapping a cylinder around the world, projecting it on the surface, and then unrolling the cylinder is an ancient idea that is still used today. Variations of the Cylindrical projection are created by changing the point of projection from the center of the earth to a point off center (on the surface or outside the earth and cylinder itself). All cylindrical maps that are oriented to the equator maintain straight meridians and latitudes that intersect at right angles (as in reality). The polar areas, however, are greatly stretched in the east-west direction.

A cone can also be placed on the earth like a cap and have the earth’s image projected on it. The Conic projection is simple to construct and gives good results for the mid-latitudes. It is not suitable for equatorial or polar regions.

30h World Federation of Trade Unions single

Globular Projection

15c Globes and Quetzal single

Globular Projection

5c Social and Rural Worker's Insurance Fund single

Cylindrical Projection

3c Oregon Territory single

Conic Projection