The Hollow Square / witness drill
Candle Witness
Pass one candle around the four benches. Each part must speak once before the hollow square is allowed to answer.
the fifth voice is listening
Start with Fa. Move clockwise unless the pressure rises; then send the candle to the part that has not been witnessed.
No bench has been witnessed yet.
Witness Line
The ledger is blank. The hollow square dislikes blank ledgers.
This widget stores nothing. The line changes with the benches you actually call.