The Calliope

A calliope (see below for pronunciation) is a musical instrument that produces sound by sending a gas, originally steam or more recently compressed air, through large whistles, originally locomotive whistles.

A calliope is typically very loud. Even some small calliopes are audible for miles around. There is no provision for varying the tone or loudness. The only expression possible is the timing and duration of the notes.

The steam calliope is also known as a steam organ or steam piano. The air-driven calliope is sometimes called a calliaphone, the name given it by its inventor, but the "Calliaphone" name is registered by a particular manufacturer.

In the age of steam, the steam calliope was particularly employed on riverboats and in circuses. In both cases, a steam supply was already available for other purposes. Riverboats supplied steam from their propulsion boilers. Circus calliopes were sometimes installed in steam-drive carousels, or supplied with steam from a traction engine, which may also supply electric power for lighting and tow the calliope in the circus parade, in which it traditionally came last. Other circus calliopes were self-contained, mounted on a carved, painted and gilded wagon pulled by horses, but the presence of other steam boilers in the circus meant that fuel and expertise to run the boiler were readily available.

Calliopes can be played by a player at a keyboard or mechanically. Mechanical operation may be by a drum similar to a music box drum, or by a roll similar to that of a player piano. Some instruments have both a keyboard and a mechanism for automated operation, others only one or the other. Some calliopes can also be played via a MIDI interface.