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A singing bird box (''boîte à oiseau chanteur'' in French) is a box, usually rectangular-shaped, which contains within a miniature automaton singing bird concealed below an oval lid and activated by means of an operating lever. Its origins are found in the city of Geneva and its invention in 1784/85 is attributed to Pierre Jaquet-Droz. The French term ''tabatière'' has also come to be used for any small decorative box resembling a snuffbox in form but not necessarily any longer used to contain snuff. ==Characteristics== This object is made up of two separate parts, habitually crafted by different makers. The outer casing is a rectangular box variable in size, although with a standard measurement of approximately 100 × 65 × 40 mm, made of base metal, precious metal, tortoiseshell or other materials. It has an oval hole, some 45 x 35 mm in its top, edged normally by a decorative metal bezel. On the front of the box there is a small slider that when it is pushed to the right, the lid or medallion lifts to a near-vertical position, and a small, mechanical feathered bird pops through a grille and stands upright at the front centre of the oval opening. Then it begins to turn from side to side, to flap its wings, move its tail up and down, open and shut its beak and – in some cases – turn its head from side to side, while producing an unbroken stream of birdsong. At the end of the performance the automaton falls back into the box and the lid closes. While the bird is calling, a decorative pierced grille appears with a bird-shaped hole cut into it through which the performer rises and falls. While singing, a bird-shaped piece of grille jumps up to cover the hole through which the automaton has passed. All bird box movements have a clock-work motor which must be wound up. This motor is doing two basic jobs: The first one is to operate a small bellows which supplies air, via a wind chest, to a whistle which produces the birdsong and the second task is to rotate a number of cams. One cam controls the note produced by the whistle, a second determines when the note will be produced and for how long, and a third one produces the motion which causes the bird to turn from side to side. In some movements the flapping of the bird's wings and its ability to turn its head are also cam-controlled, in others not. The final cam determines the point at which the song ends, the bird folds away, the lid drops and the motor stops. The bird's beak movements are always connected to the cam controlling the air supply to the whistle: in this way the sound and beak movements are automatically synchronized. The whistle consists of a miniature organ pipe containing a close-fitting piston which can be moved up and down to give a range of notes of over an octave. The winged performer varies in size but 30 mm from beak to tail is common. The bird itself consists of a brass frame to which two half-body shells are attached, each half-shell having one wing pivoted to its side. To dress a few of them, feathers of South American hummingbirds were utilized in the past for their brilliant red, green and blue iridescent colours, which gave a well feathered bird an almost jewel-like appearance, but nowadays they are no longer available. As for the movement, this is a compact device located between two brass plates. Two mechanisms have been used during the more than two centuries of singing bird boxes, each with its own characteristics: The fusee-driven movement and the going-barrel movement. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Singing bird box」の詳細全文を読む スポンサード リンク
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