A dark Cave. In the middle, a Caldron boiling. Thunder.

                Enter the three Witches.

       1 WITCH.  Thrice the brinded cat hath mew'd.
       2 WITCH.  Thrice and once, the hedge-pig whin'd.
       3 WITCH.  Harpier cries:—'tis time! 'tis time!
       1 WITCH.  Round about the caldron go;
    In the poison'd entrails throw.—
    Toad, that under cold stone,
    Days and nights has thirty-one;
    Swelter'd venom sleeping got,
    Boil thou first i' the charmed pot!
       ALL.  Double, double toil and trouble;
    Fire burn, and caldron bubble.
       2 WITCH.  Fillet of a fenny snake,
    In the caldron boil and bake;
    Eye of newt, and toe of frog,
    Wool of bat, and tongue of dog,
    Adder's fork, and blind-worm's sting,
    Lizard's leg, and owlet's wing,—
    For a charm of powerful trouble,
    Like a hell-broth boil and bubble.
       ALL.  Double, double toil and trouble;
    Fire burn, and caldron bubble.
       3 WITCH.  Scale of dragon; tooth of wolf;
    Witches' mummy; maw and gulf
    Of the ravin'd salt-sea shark;
    Root of hemlock digg'd i the dark;
    Liver of blaspheming Jew;
    Gall of goat, and slips of yew
    Sliver'd in the moon's eclipse;
    Nose of Turk, and Tartar's lips;
    Finger of birth-strangled babe
    Ditch-deliver'd by a drab,—
    Make the gruel thick and slab:
    Add thereto a tiger's chaudron,
    For the ingrediants of our caldron.
       ALL.  Double, double toil and trouble;
    Fire burn, and caldron bubble.
       2 WITCH.  Cool it with a baboon's blood,
    Then the charm is firm and good.

  from Macbeth

The above appears at the beginning of Act IV, Scene 1