«This piano was tuned to the fork of the house, not to the fork of today. Four strings were left slack; whoever tightens them and plays the chord will open the music desk.»
Play the string beside the tuning fork and turn the pin until the beat disappears. While the wobble can still be heard, it is not there.
The music desk of the Erard will not lift: it is jammed from inside, and the mechanism answers to four properly tensioned strings. The house tuned to four hundred and thirty-five, not to four hundred and forty, so a modern pocket fork is worth nothing here. What is worth something is the ear: two almost equal notes wobble, and when they stop wobbling they are the same note.
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