FOLGER_140406_074
Existing comment: What's Going On?
Macbeth's question, "Who sinks that cauldron?" is -- among other things -- a description of what's happening on stage. Shakespeare often included such lines because he knew that a spectator might have blocked view, or be unable to see into a crowd of actors. As Macbeth speaks, the witches' cauldron descends through the stage trapdoor.
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