Whispering Galleries

A whispering gallery is defined as “a space beneath a dome or arch in which sounds produced at certain points are clearly audible at certain distant points,” in the Free Dictionary, a free online dictionary.

Wikipedia, the free online encyclopedia, defines a whispering gallery similarly: “a gallery beneath a dome or vault or enclosed in a circular or eliptical area in which whispers can be heard clearly in other parts of the building.”

There are many examples of whispering galleries around the world, some natural, some artificial constructions. The viewing areas in planetariums generally have a projection dome on top of a circular wall. The whispering can be heard around the inside of the wall. Sometimes you can hear people on the opposite side of the room better than you can hear your neighbor.

Large buildings and public spaces dominate when it comes to finding whispering galleries in human structures. Buildings that serve more than a utilitarian purpose, where the costs can be justified for pride or beauty, are good candidates. Churches and other large public buildings often have superfluous structures in them, like domes and arches. Large, curved surfaces make the best galleries.

Grand Central Station, a New York railway station built when monumental was the word, is such a building. In it is an oyster bar called the Grand Central Oyster Bar, which is entered via an arched hallway. People in opposite corners of the hallway can hear each other whisper.

Saint Paul’s Cathedral in London has a dome. The current Saint Paul’s does, anyway. The original one, built of wood by the Saxons and lost to fire in 675, didn’t. Neither did any of the many incarnations of the cathedral built over the next thousand years on the same spot. The present version, completed in 1708, was designed by Christopher Wren and is the first to have a dome. From ground level one must climb 259 steps before entering the dome. Once inside, the whispering gallery effect can be heard.

The Mapparium, in Boston, goes beyond arches and domes. It’s a stained glass globe, fully enclosed in all dimensions. All points share acoustical effects with at least one other point. It was built in 1935 and shows the Earth’s political boundaries in stained glass. People can walk on a glass sided bridge right through the center and look out through a map of the world all around them.

Physicist William Hartmann and his team have recorded many acoustical effects in the sphere. There is the classical whispering gallery, where people on opposite sides in the structure can hear each other. There are places where sounds are amplified or muted. A sound source moving away across the bridge can seem to flip back and forth from ear to ear.

I can’t think of a nicer place for an acoustically-inclined person.

rjb