Editor:

Barry Evans' column about the limitations of accuracy of world maps (Field Notes, July 29) has one important omission, Bucky Fuller's Dymaxion World Map.

Imagine a globe centered inside of a geodesic solid, such as an icosahedron. With a light at the center of the globe, the map is projected onto the facets of the icosahedron, which is then unfolded along its edges to form a flat map. Distortion is very much reduced, as the angle of non-tangent projection is much smaller than the "conventional" mapping methods.

Bucky was awarded a patent for this mapping method in 1946. Incidentally, the patent office had ruled in 1900 that no other world map type patents would be awarded because all possible methods had

been discovered. They recanted.

Clay Johnson, Trinidad

Barry Evans responds: I was saving a discussion of Fuller's Dymaxion World Map ("Dymaxion" comes from DYNamic-MAXimum-tensION) for a future column on Platonic solids, the icosahedron being the fifth and final such solid (regular polyhedron), but anyway... Fuller's map does indeed minimize distortion of land masses, but at great cost - the world's oceans are a mess! In projecting a sphere to a flat surface, something always has to give.

Incidentally, Bucky may have thought that his was the first world map patent to be issued since 1900, but he was beaten to the gun by the 1913 patent issued to Bernard Cahill for his Butterfly Map.

Sweet Spot: Clay Johnson wins a Bon Boniere sundae for sending our favorite letter of the week.