i.e., You wait for horrible events to befall mankind.
Note that "nature's mischief" is not nature committing mischief, but rather, mischief done to nature.
For more on this passage please see the annotations at the bottom of the main page of Macbeth 1.5
How to cite this article:
Mabillard, Amanda. Macbeth Glossary. Shakespeare Online. 20 Aug. 2000. (date when you accessed the information) < http://www.shakespeare-online.com/plays/macbeth/macbethglossary/macbeth1_1/macbethglos_waiton.html >.