Kugel ball
A kugel fountain (also called a floating sphere fountain or by the tautological name Kugel ball) is a water feature or sculpture where a sphere sitting in a spherical pocket on a pedestal is supported by a thin film of water. Pressurized water flows between the sphere and pocket, creating a mechanical fluid bearing that is nearly frictionless. The sphere can weigh thousands of pounds, but the efficient bearing allows it to be spun by the force of a hand. It is often made from granite. Ring sculptures that rotate on an axis are also built.
Kugel fountains can be found all over the world. Many are at popular tourist destinations, such as science museums shopping centers, lobbies, and gardens.
The term kugel is from the German word Kugel for ball or sphere.
Simplified diagram of the workings of a kugel fountain
Floating celestial globe, weighing nine tons, being spun by a child.]]
Lansdale station, Railroad Plaza, Lansdale, Pennsylvania
51°40′19″N 1°16′46″W / 51.671882°N 1.279409°W
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