Assertion: tuba's valve | /r/HasProperty | actuated by left hand
Facets:
Source sentences:
text: The rotary valve was actuated by the left hand, and featured a length of tubing that lowered the pitch by either a half-step (F#) or a whole-step (F).
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.