Apparat, mit dem eine Kartoffel eine andere umkreisen kann (Apparatus Whereby One Potato Can Orbit Another), 1969.

Kartoffelmaschine (Potato Machine) demonstrates both Polke's use of simple repeatedly incorporated the potato into two- and three-dimensional works. In this piece, a modified stool makes reference to Marcel Duchamp's Bicycle Wheel, an early icon of 20th-century sculpture that incorporated found objects. Here Polke transforms the ordinary: as one presses the button, the potato begins an orbit beneath the stool as if it were the center of the universe.

source: walkerart.org