Rhubarb, senna

Macbeth, [5.3.51-57]. Macbeth. “If thou couldst, doctor, cast/ The water of my land, find her disease,/ And purge it to a sound and pristine health,/ I would applaud thee to the very echo,/ That should applaud again. –Pull’t off, I say.–/ What rhubarb, senna, or what purgative drug/ Would scour these English hence? Hear’st thou of them?”

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Senna.