Assertion: french horn's valve | /r/HasProperty | operated with left hand
Facets:
Source sentences:
text: Horns have valves, operated with the left hand, to route the air into extra tubing to change the pitch.
text: A creation unique to the United States was the double-bell euphonium, featuring a second smaller bell in addition to the main one; the player could switch bells for certain passages or even for individual notes by use of an additional valve, operated with the left hand.