SO… WHAT IS IT AND HOW DOES IT WORK? The Foucault Pendulum is named for the French physicist Jean Foucault who conceived the idea in 1851 to demonstrate the rotation of the earth. Foucault’s concept was the first valid demonstration of the earths rotation using laboratory conditions rather than astronomical observations and proved that the earth revolves around the sun and not the other way round.This fantastic desktop version of Foucaults Pendulum consists of a weighted bob suspended by wire over a small bowl of sand. When you start the pendulum moving, the bob inscribes lines in the sand. Nothing much happens at first… just a line in the sand, but bit by bit you notice a pattern begin to emerge in the grains. How can that be? How can these amazing geometric patterns be occurring when the weighted bob is just swinging backwards and forwards on a single axis?The Foucault Pendulum proves that the swinging bob isn’t changing direction, but the earth has rotated an infinitesimally small amount between the start and finish of one swing of the line and as the pendulum continues to swing, so the pattern expands and changes directions.Standing 38cm tall, the Foucault Pendulum is a fantastic addition to any desk and is a soothing way to contemplate matters of great importance.