The two high value stamps
of a four stamp set commemorating the 50th anniversary of Japan
joining the Universal Postal Union issued in 1927 are map stamps with
the same design.
William Horney (“Miniature Maps of the World,” Weekly
Philatelic Gossip vol. 46, no. 12, May 22, 1948, p. 369.) describes
the stamp this way: “This excellent map of the world on the
Sanson-Flamsteed or sinusoidal projection centered on Japan...
(italics mine).” Walter Klinefelter (“The World in One’s VestPocket:
An Atlas on Postal Paper...,” Scott’s Monthly Journal September 1943,
p. 207, describes it more accurately as follows: “Mollweide’s
elliptical equal-area projection was employed by Japan in 1927 for an
all-inclusive map design which is without benefit of parallels and
In fact the projection is the Mollweide projection in
which all meridians but the central on are elliptical arcs. Unlike the
Sanson-Flamsteed which crowds the polar areas the Mollweide opens them
up. The map is centered on Japan and includes a carrier pigeon with a
letter in its beak.