A kugel fountain (also called a "floating" sphere fountain or by the pleonasmic name kugel ball) is a

water feature In landscape architecture and garden design, a water feature is one or more items from a range of fountains, jeux d'eau, pools, ponds, rills, artificial waterfalls, and streams. Before the 18th century they were usually powered by gravity, ...

or sculpture where a

sphere A sphere () is a geometrical object that is a three-dimensional analogue to a two-dimensional circle. A sphere is the set of points that are all at the same distance from a given point in three-dimensional space.. That given point is th ...

sits in a fitted hollow in a pedestal, and is supported by

aquaplaning Aquaplaning or hydroplaning by the tires of a road vehicle, aircraft or other wheeled vehicle occurs when a layer of water builds between the wheels of the vehicle and the road surface, leading to a loss of traction that prevents the vehicle fr ...

on a thin film of water. Pressurized water flows between the sphere and socket, creating a mechanical

hydrostatic bearing Fluid bearings are bearings in which the load is supported by a thin layer of rapidly moving pressurized liquid or gas between the bearing surfaces. Since there is no contact between the moving parts, there is no sliding friction, allowing flu ...

that is nearly frictionless. The sphere can weigh thousands of kilograms, but the efficient bearing allows it to be spun by the force of a hand. The sphere does not float, being denser than water; it is often made from

granite Granite () is a coarse-grained ( phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies under ...

. The hydraulics of the fountain can be controlled so that the axis of rotation of the sphere changes continually. Ring sculptures that rotate on an

axis An axis (plural ''axes'') is an imaginary line around which an object rotates or is symmetrical. Axis may also refer to: Mathematics * Axis of rotation: see rotation around a fixed axis * Axis (mathematics), a designator for a Cartesian-coordinat ...

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 ''

''.

Locations of kugel fountains

Notes

Gallery

File:Kugel June 24 2021.jpg, World globe, Jack C. Taylor Conference Center of the

United States Naval Institute The United States Naval Institute (USNI) is a private non-profit military association that offers independent, nonpartisan forums for debate of national security issues. In addition to publishing magazines and books, the Naval Institute holds se ...

, Annapolis File:Reaching for the Stars.jpg,

Celestial globe Celestial globes show the apparent positions of the stars in the sky. They omit the Sun, Moon, and planets because the positions of these bodies vary relative to those of the stars, but the ecliptic, along which the Sun moves, is indicated. Th ...

, weighing nine tons, being spun by a child. File:Kugel Ball in Lansdale.jpg,

Lansdale station Lansdale station, also known as the Lansdale Transportation Center, is a SEPTA Regional Rail station in Lansdale, Pennsylvania. Located at Main Street ( PA 63) and Green Street, it serves the Lansdale/Doylestown Line. It was originally built in 19 ...

, Railroad Plaza,

Lansdale, Pennsylvania Lansdale is a borough in Montgomery County, Pennsylvania, United States. It is a densely-populated commuter town, with many residents traveling daily to Philadelphia using SEPTA Regional Rail's Lansdale/Doylestown Line. In 1900, 2,754 people live ...

File:Malta - Sliema - Triq It-Torri - floating sphere fountain 01 ies.ogv,

Sliema Sliema ( mt, Tas-Sliema ) is a town located on the northeast coast of Malta in the Northern Harbour District. It is a major residential and commercial area and a centre for shopping, bars, dining, and café life. It is also the most densely po ...

Malta Malta ( , , ), officially the Republic of Malta ( mt, Repubblika ta' Malta ), is an island country in the Mediterranean Sea. It consists of an archipelago, between Italy and Libya, and is often considered a part of Southern Europe. It lies ...

File:Bottrop - Kirchplatz - Kugelbrunnen 02 (0) ies.ogv, The Kirchplatz fountain in

Bottrop Bottrop () is a city in west-central Germany, on the Rhine–Herne Canal, in North Rhine-Westphalia. Located in the Ruhr industrial area, Bottrop adjoins Essen, Oberhausen, Gladbeck, and Dorsten. The city had been a coal-mining and rail cent ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

, with pigeon File:Kugel fountain dueren germany.jpg, Kugel fountain in Dueren,

File:Wuppertal Willy-Brandt-Platz 2014 016.webm, The transplanted Döppersberger Brunnen in its new location in the Willy-Brandt-Platz in

Wuppertal Wuppertal (; "''Wupper Dale''") is, with a population of approximately 355,000, the seventh-largest city in North Rhine-Westphalia as well as the 17th-largest city of Germany. It was founded in 1929 by the merger of the cities and tow ...

References

External links

* {{cite journal , last1=Snoeijer , first1=Jacco H. , last2=der Weele , first2=Ko van , title=Physics of the granite sphere fountain , journal=American Journal of Physics , date=November 2014 , volume=82 , issue=11 , pages=1029–1039 , doi=10.1119/1.4886365 , url=http://stilton.tnw.utwente.nl/people/snoeijer/Papers/2014/SnoeijerAJP14.pdf, bibcode=2014AmJPh..82.1029S
Kugel fountain FAQ

Terracache dedicated to the kugel fountain.

Waymarking list of large kugel fountains, with GPS coordinates and images.
Balls Fountains Garden ornaments Outdoor sculptures

Locations of kugel fountains

Notes

Gallery

See also

References

External links