All at once, the ground was no longer beneath my feet. I felt myself spinning and bouncing off the protrusions of a vertical shaft–practically a well. My head hit a sharp rock, and I lost consciousness.
Bilbo's fall in JRR Tolkien's "The Hobbit":
Quite suddenly Dori, now at the back again carrying Bilbo, was grabbed from behind in the dark. He shouted and fell; and the hobbit rolled off his shoulders into the blackness, bumped his head on hard rock, and remembered nothing more.
