Round about the cauldron go;
In the poison’d entrails throw.
Toad, that under cold stone
Days and nights hast thirty-one
Swelter’d venom sleeping got,
Boil thou first i’ the charmed pot.
– William Shakespeare
Macbeth, Act 4, Scene 1. As the Three Witches gather around their boiling cauldron to brew up their evil spell, the First witch chants this verse. An ominous tone is created by the chanting, the references to “poisoned entrails” and “venom,” and the thunder that accompanies the entrance of the Witches.