STORY Clock: a favorite piece of engineered kinetic art in my collection- a spherical magnet hovers one centimeter from the face of this amazing clock and orbits in a circle to indicate the time- for this video I selected an orbit period of a minute to show off the motion. This kind of levitation uses a control system with adjustable electromagnet coils in a feedback loop with Hall effect sensors which allow for fine tuning of a magnetic field to precisely balance the pull of gravity. Astonishin