A whispering gallery is usually a circular, hemispherical, elliptical or ellipsoidal enclosure, often beneath a dome or a vault, in which whispers can be heard clearly in other parts of the gallery. Such galleries can also be set up using two parabolic dishes. Sometimes the phenomenon is detected in caves.
Theory
editA whispering gallery is most simply constructed in the form of a circular wall, and allows whispered communication from any part of the internal side of the circumference to any other part. The sound is carried by waves, known as whispering-gallery waves, that travel around the circumference clinging to the walls, an effect that was discovered in the whispering gallery of St Paul's Cathedral in London.[1] The extent to which the sound travels at St Paul's can also be judged by clapping in the gallery, which produces four echoes.[2] Other historical examples[3][4][5] are the Gol Gumbaz mausoleum in Bijapur, India and the Echo Wall of the Temple of Heaven in Beijing. A hemispherical enclosure will also guide whispering gallery waves. The waves carry the words so that others will be able to hear them from the opposite side of the gallery.
The gallery may also be in the form of an ellipse or ellipsoid,[4] with an accessible point at each focus. In this case, when a visitor stands at one focus and whispers, the line of sound emanating from this focus reflects directly to the focus at the other end of the gallery, where the whispers may be heard. In a similar way, two large concave parabolic dishes, serving as acoustic mirrors, may be erected facing each other in a room or outdoors to serve as a whispering gallery, a common feature of science museums. Egg-shaped galleries, such as the Golghar Granary at Bankipore,[3] and irregularly shaped smooth-walled galleries in the form of caves, such as the Ear of Dionysius in Syracuse,[4] also exist.
Examples
editIndia
edit- The Gol Gumbaz in Bijapur, India.[3]
- The Golghar Granary in Bankipore, India.[3]
- The Victoria Memorial in Kolkata.[3]
United Kingdom
edit- St Paul's Cathedral in London is the place where whispering-gallery waves were first discovered by Lord Rayleigh c. 1878.[6]
- Gloucester Cathedral has a whispering gallery.[7]
- The Berkeley Wetherspoons Bristol has a whispering gallery.[8]
United States
edit- Grand Central Terminal in New York City: a landing amid the Oyster Bar ramps, in front of the Oyster Bar restaurant [9]
- Statuary Hall in the United States Capitol.[3]
- Salt Lake Tabernacle in Salt Lake City, Utah[3]
- Centennial fountain in front of Green Library at Stanford University in California[10]
- Gates Circle, Buffalo, New York[11]
- The Whispering Arch in St. Louis Union Station[12]
- Charles Stover Bench, Central Park, New York, New York [13]
- Waldo Hutchins Bench, Central Park, New York, New York[14]
Other parts of the world
edit- The Echo Wall in the Temple of Heaven in Beijing.[5]
- Basilica of St. John Lateran, Rome.[4]
- The Salle des Caryatides in the Louvre, Paris, France.[4]
- Ear of Dionysius cave in Syracuse, Sicily.[4]
- Banco dos Namorados (Lovers' bench) in Santiago de Compostela, Spain.[15]
In science
editThe term whispering gallery has been borrowed in the physical sciences to describe other forms of whispering-gallery waves such as light or matter waves.[16]
See also
editReferences
edit- ^ Lord Rayleigh, The problem of the whispering gallery, Philos. Mag. 20, 1001,1910.
- ^ O. Wright, Gallery of Whispers, Physics World 25, No. 2, Feb. 2012, p. 31. [dead link]
- ^ a b c d e f g Raman, C. V. (1922). "On whispering galleries" (PDF). Bull. Indian Assoc. Cultiv. Sci. 7: 159–172 – via IAS Fellows Publications.
- ^ a b c d e f W. C. Sabine, Collected Papers on Acoustics (Harvard University Press, Cambridge MA) 1922, p. 255.
- ^ a b Peiping (American National Red Cross, American Red Cross Embassy Club) 1946, p. 17.
- ^ Lord Rayleigh, Theory of Sound, vol. II, 1st edition, (London, MacMillan), 1878.
- ^ "Gloucester Cathedral | Whispering Gallery".
- ^ "Berkeley Wetherspoons".
- ^ "Grand Central Terminal Whispering Gallery". Atlas Obscura. Retrieved 10 June 2017.
- ^ "Centennial Fountain - Stanford, CA - Whispering Galleries on Waymarking.com". www.waymarking.com. Retrieved 23 October 2017.
- ^ "Gates Circle, New York, NY". Buffalo as an Architectural Museum. Retrieved 10 June 2017.
- ^ Waymarking.com, St. Louis Union Station Whispering Arch
- ^ "Charles Stover Bench". Official Website of the New York City Department of Parks & Recreation. Retrieved 10 June 2017.
- ^ "Waldo Hutchins [Bench]". Official Website of the New York City Department of Parks & Recreation. Retrieved 10 June 2017.
- ^ "El Banco dos Namorados de Santiago, donde intercambiar susurros a catorce metros". Quincemil (in Spanish). 2020-10-20. Retrieved 2024-03-24.
- ^ Katsnelson, Boris G.; Petrov, Pavel S. (2019-09-01). "Whispering gallery waves localized near circular isobaths in shallow water". The Journal of the Acoustical Society of America. 146 (3): 1968–1981. Bibcode:2019ASAJ..146.1968K. doi:10.1121/1.5125419. ISSN 0001-4966. PMID 31590497. S2CID 203926782.
External links
edit
- Ear of Dionysius: visiting information, videos and sounds of this cave.
- Grand Central Station: visiting information, videos and sounds of the whispering gallery.
- St Paul's Cathedral: visiting information, videos and sounds of the whispering gallery.
