Assertion: piano's design | /r/CapableOf | feature special fourth pedal
Facets:
Source sentences:
text: The design also featured a special fourth pedal that coupled the lower and upper keyboard, so when playing on the lower keyboard the note one octave higher also played.
text: The design also featured a special fourth pedal that coupled the lower and upper keyboard, so when playing on the lower keyboard the note one octave higher also played.