Whispering gallery to the walls, an effect that was discovered in the whispering gallery of St Paul's Cathedral in London. The extent to which the sound travels at St Paul's can also be judged by clapping in the gallery, which produces four echoes. Other historical examples are the Gol Gumbaz mausoleum in Bijapur 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
491 Gallery 491 Gallery The 491 Gallery was a squatted social centre and multi-disciplinary gallery in Leytonstone, London, England, that operated from 2001 to 2013. Taking its name from its street number, 491 Grove Green Road, the former factory was home to a community-led art organisation and served as an exhibition space for a diverse range of artists of different origins working in varied media. It contained a range of art and music studios, which were used to host workshops, classes and musical rehearsals. The building was subsequently demolished in 2016. The building, originally a factory, was later used as a storage