Fig. 460.08 Symmetrical Contraction of Vector Equilibrium:
Jitterbug System: If the vector equilibrium
is constructed with circumferential vectors only and
joined with flexible connections, it will contract
symmetrically due to the instability of the square faces.
This contraction is identical to the contraction
of the concentric sphere packing when its nuclear sphere
is removed. This system of transformation has
been referred to as the "jitterbug." Its various phases
are shown in both left and righthand contraction:
 Vector equilibrium phase: the beginning of the transformation.
 Icosahedron phase: When the short diagonal dimension
of the quadrilateral face is equal to the
vector equilibrium edge length, 20 equilateral triangular
faces are formed.
 Further contraction toward the octahedron phase.
 Octahedron phase: Note the doubling of the edges.
