What is a curved wooden horn about three feet long, with a cupped mouthpiece and a bell, used by the Swiss to sound the ranz des vaches and other melodies. Its notes are open harmonics of the tube called?

alphorn — A curved wooden horn about three feet long, with a cupped mouthpiece and a bell, used by the Swiss to sound the ranz des vaches and other melodies. Its notes are open harmonics of the tube. (Webster's 1913.)

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