Whispering-gallery wave Whispering-gallery wave Whispering-gallery waves, or whispering-gallery modes, are a type of wave that can travel around a concave surface. Originally discovered for sound waves in the whispering gallery of St Paul’s Cathedral, they can exist for light and for other waves, with important applications in nondestructive testing, lasing, cooling and sensing, as well as in astronomy. Whispering-gallery waves were first explained for the case of St Paul's Cathedral circa 1878 by Lord Rayleigh, who revised a previous misconception that whispers could be heard across the dome but not at any intermediate position. He explained the phenomenon of travelling whispers with
St Paul's Cathedral and wide, runs a cornice which supports the "Whispering Gallery" so called because of its acoustic properties: a whisper or low murmur against its wall at any point is audible to a listener with an ear held to the wall at any other point around the gallery. It is reached by 259 steps from ground level. The dome is raised on a tall drum surrounded by pilasters and pierced with windows in groups of three, separated by eight gilded niches containing statues, and repeating the pattern of the peristyle on the exterior. the dome rises above a gilded cornice at