"Silence: A little test, a different way of painting"
Might be a bit rough, but that's the meaning of it. And no information on the trigger method. It looks like it's timed, but I don't know how the chain drive is going to generate enough force: revolvers have notoriously heavy trigger pulls (in this case, lessened by the hammer being cocked).
I imagine it's based on how much she breathes or talks.
There's a tube that looks like it goes from her mouth and attaches to the dial, and that holds one of the bars in place. If the dial hits a high enough pressure from the girl talking too much or breathing through her mouth too much, then it'll release the metal bar(s). There's more than one bar, so I can't be certain if that dial holds the bars that are in view. If the screw-handle (whatever it's called) on the "Silence" wrap isn't tightened and the bars release, then the whole strap falls, turns the wheel fast enough to pull the trigger, and there's a new Jackson Pollock painting on the nearest surface behind the girl.
At a guess? It's something designed to make the girl be quiet.
