Classifications
polyconic
globular
Graticule
Meridians: Central meridian is straight. Other meridians are circular arcs, equally spaced along the equator but not along other parallels.
Parallels: Parallel straight lines equally spaced on the meridians 90° from the center.
Poles: Points.
Symmetry: About the central meridian or the equator.
Scale
True along the central meridian and the equator.
Distortion
Moderate for a hemisphere.
Considerable area and shape distortion if used beyond the 90th meridians.
Usage
Hemispheric maps, common in atlases between 1850 and 1925.
Similar projections
Van der Grinten IV has parallels of different curvature and is extended to a world map.
Azimuthal equidistant (equatorial aspect) has complex curves for meridians and parallels.
Fournier globular I has elliptical arcs for meridians.
Origin
Presented by Giambattista Nicolosi (1610-70) of Rome in 1660.
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.