Yet Frodo began to hear, or to imagine that he heard, something else: like the faint fall of soft bare feet. It was never loud enough, or near enough, for him to feel certain that he heard it; but once it had started it never stopped, while the Company was moving. But it was not an echo, for when they halted it pattered on for a little all by itself, and then grew still.

Autor: J.R.R. Tolkien