Geocart menu class: Conic
Cordiform (heart shaped)
Meridians: Central meridian is a straight line. Other meridians are complex curves connecting points equally spaced along each parallel of latitude and concave toward the central meridian.
Parallels: Concentric circular arcs spaced at true distances along the central meridian. One pole (usually the North Pole) is the center for these circular arcs.
Symmetry: About the central meridian
True along the central meridian and along each parallel
Free of all distortion only along the central meridian
Frequently used for world and some continental maps of the 16th and 17th centuries. Replaced by the Bonne projection for continental maps. No longer used except as a novelty.
Developed by Johannes Stabius (Stab) (?-1522) of Vienna about 1500 and promoted by Johannes Werner (1466-1528) of Nuremberg in 1514
Bonne projection is a general form on which the parallels are also circular arcs but are not generally centered on a pole. The Werner is the polar limiting form.
In 1904, Wilhelm Schjerning interrupted the Werner projection, centered on the South Pole, with three central meridians and three "petals" for a world map emphasizing the oceans.
Goode Polar Equal-Area projection, presented by John Paul Goode in 1928, is an interrupted Werner projection, centered on the North Pole and using several central meridians to display continents in a flowerlike pattern.
“Tetrahedral” projection, presented by John Bartholomew by 1944, is a combination of the Polar Azimuthal Equidistant projection from the pole to the tropic line of the same hemisphere and an interrupted Werner from there to the opposite pole, some adjustment being made to obtain a fit. The North Pole is the center for a map of land masses, and the South Pole is the center for an ocean map.
In 1968, W. William-Olsson of Sweden combined the northern Polar Lambert Azimuthal EqualArea projection, extending to latitude 20° N., with four identical lobes extending to the South Pole. The lobes are based on the Werner projection but are compressed north-south and expanded east-west to fit the Lambert and to retain equality of area.
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.