What is foreshadowing?

There is a lot of foreshadowing in this story.

1) Some of Rainsford's initial dialogue are examples of foreshadowing.

"What I felt was a -- a mental chill; a sort of sudden dread."

2) Rainsford was an expert hunter, but he did not recognize the agonizing screams of the animal. This foreshadows the mysterious hunt.

"Rainsford heard a sound. It came out of the darkness, a high screaming sound, the sound of an animal in an extremity of anguish and terror. He did not recognize the animal that made the sound; he did not try to; with fresh vitality he swam toward the sound. He heard it again; then it was cut short by another noise, crisp, staccato."