Square Wave Horizon: A favorite kinetic art object in my collection- with a snap of the wrist waves are sent propagating, folding the structure into a tight curl- and a reverse snap will bring back the initial flat square state. Created from twenty interlocking right angle metal rods, mounted horizontally with accompanying base and grips at each end which allows one to rotate the structure to and fro. An important design feature is that each right angle rod is limited to move through about 45 de