#
Septvaginta Duarus Planus Vacuus

#

This cherry orb (with a cherry and holly sign, and brass wire) is *Septvaginta
Duarus Planus Vacuus*. The geometric form consists of sixty "kites"
and twenty equilateral triangles. I call the underlying form a "propello-icosahedron"
because if you look at each triangle, you will see it is surrounded by
three kites which spiral like a propellor. There are 20 of these
groups (arranged as in an icosahedron) in the complete form. The
kites are particularly interesting because they have three equal face angles.
Although in the style of Leonardo da
Vinci's polyhedron models, this is a new polyhedron, not previously
described in the mathematical literature. As Leonardo's drawings
of polyhedra in this open-face style were important in the Renaissance
for disseminating knowledge of geometry, I chose this style for this first
model of this polyhedron.

copyright 1999, George W. Hart