Cuckoo clock

A cuckoo clock is a typically pendulum-regulated clock that strikes the hours with a sound like a common cuckoo's call and has an automaton cuckoo bird that moves with each note. Some move their wings, open/close the beak while leaning forward, whereas others only the bird's body is leaned forward. The mechanism to produce the cuckoo call has been in use since the middle of the 18th century and has remained almost without variation until the present.

It is unknown who invented it and where the first one was made. It is thought that much of its development and evolution was made in the Black Forest area in southwestern Germany (State of Baden-Württemberg), the region where the cuckoo clock was popularized. The cuckoo clocks were exported to the rest of the world from the mid 1850s on. Today, the cuckoo clock is one of the favourite souvenirs of travelers in Germany, Switzerland, and Austria. It has become a cultural icon of Germany.

The design of a cuckoo clock is now conventional. Most are made in the "traditional style" (also known as "carved") or "chalet" to hang on a wall. In the "traditional style" the wooden case is decorated with carved leaves and animals. They have an automaton of the bird that appears through a small trap door while the clock is striking. The bird is often made to move as the clock strikes, typically by means of an arm that lifts the back of the carving.

There are two kinds of movements: one-day (30-hour) and eight-day clockworks. Some have musical devices, and play a tune on a Swiss music box after striking the hours and half-hours. Usually the melody sounds only at full hours in eight-day clocks and both at full and half hours in the one-day timepieces. Musical cuckoo clocks frequently have other automata which move when the music box plays. Today's cuckoo clocks are almost always weight driven, though a very few are spring driven. The weights are made of cast iron in a pine cone shape and the "cuc-koo" sound is created by two tiny gedackt (pipes) in the clock, with bellows attached to their tops. The clock's movement activates the bellows to send a puff of air into each pipe alternately when the timekeeper strikes.

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Wikipedia