"Ugh! He gives me cold chills," cried Darrin.
"He does the same to me," sighed Dick, "but it's a plain case of duty to follow him until we can turn him over to those who'll take good care of the poor fellow."
Just as Amos Garwood was on the point of vanishing from their view, the two schoolboys started forward, more cautiously than before.
Back of them in the woods, far away, sounded a boyish war-whoop.
"Hi-yi-yi-yi-yoop!" answered Dave Darrin.
Amos Garwood started forward with a bound like that of a deer. Then his long legs went into rapid operation. Prescott and Darrin ran onward as fast as they could go. They were trained to running, too, but this "master of the world" set them a pace that no fourteen-year-old boys on earth could have followed with any hope of success.
"Whoop, but he's an airship for speed!" gasped Dave Darrin.
"We couldn't catch him with a locomotive," confessed Dick, when, panting, he was at last obliged to halt.
"Hear him—-going," gasped Darrin.
"I can't hear him," confessed Dick, after a moment of listening.