The vibrations of the lips, focused and amplified by the mouthpiece and directed into the tube, cause the column of air inside the tube to vibrate, and as in all wind instruments, the vibrating air column produces the sound of the instrument.

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This may sound faintly ridiculous, but the finished object looks like a deeply satisfying classical column.

ECONOMIST: American contemporary art

The question for this column, however, is whether the economic assumptions weaved into certain storylines are sound.

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