He urged his own horse forward a little, and the shadow stopped instantly.

Then he knew that he had been seen, and he sat motionless in the saddle for an instant or two, not knowing what to do.
After all, the man on horseback might be a friend.

He might be some scout from a band of rangers, coming to join Jackson; and not yet sure that the army in the woods was his.

Recovering from his indecision he rode forward a little and called: "Who are you ?" The shadow made no reply, and horse and rider were motionless.

They seemed for an instant to be phantoms, but then Harry knew that they were real.