Time-passing, in operation

Two clear discs, each cut with spokes, one behind the other over a light. A motor turns one of them, slowly. Where the spokes of one cross the spokes of the other, a third pattern appears that neither disc has on it, and it turns much faster than the motor does. In the middle, on the turning mount, an hourglass goes round with it, so the sand never has time to finish.

Drag the picture to turn the disc yourself.

A simulation of Idő-töltés (Time-passing), Naomi Devil, 2016, a cybernetic sculpture built round Nicolas Schöffer’s hourglass for the Hungarikon collection. The artist describes laser-engraved acrylic discs turned by a motor, lit by LEDs, whose moiré recalls the infinity sign, and an hourglass whose sand flows in endless circulation. This page draws that mechanism; the real discs may differ in their count of spokes and their speed. Photograph of the work: Darabos György, on Wikimedia Commons, CC BY-SA 4.0; the tab icon is a crop of it under the same licence.