Assertion: vibraphone's bar | /r/HasProperty | arranged in semitone
Facets:
value: in the form of a trapezoid
type: OTHER
Source sentences:
text: By that time, the instrument had already been popularized to some extent by Michael Josef Gusikov, whose instrument was the five-row xylophone made of 28 crude wooden bars arranged in semitones in the form of a trapezoid and resting on straw supports.