The Harmonograph, invented in the 1860s, is a mathematical instrument which draws visualisations of musical chords using the combined motions of several pendulums. It reveals the nature of harmony and mathematics, and shows quite plainly that number, the one indisputable truth in the universe, creates musical and visual beauty. There are several different designs and an infinite number of forms that can be created.

To find out more about the Harmonograph, visit www.harmonograph.info.