Rolling ball sculpture
This article needs additional citations for verification. (August 2010)
A rolling ball sculpture (sometimes referred to as a "marble run", "ball run", "gravitram", "kugelbahn", or "rolling ball machine") is a form of kinetic art – an art form that contains moving pieces – that specifically involves one or more rolling balls. A version where marbles compete in a race to win is called a marble race.
- Knikkers, Jelle (October 28, 2015) "Marble Run Records" Jelle's Marble Runs Accessed:December 31, 2019