But this rough magic
I here abjure; and when I have required
Some heavenly music, which even now I do,
To work mine end upon their senses that
This airy charm is for, I’ll break my staff,
Bury it certain fathoms in the earth,
And deeper than did ever plummet sound
I’ll drown my book.
– William Shakespeare
The Tempest, Act 5, Scene 1. Prospero decides to renounce his magical powers, with which he controlled the island. After he has completed his last bit of magic, he will break and bury his staff and "drown" his magic book. In doing so he will return the island to its natural state once more. He realizes that it was his obsession with magic that led to his political downfall and exile.