"Don't get out of the car, Helen," called Matt, as the girl was about to climb over the rail. "You can't stay here after this."
Her resolve to remain with her father was unshaken; but there was a bright light in her eyes which Matt had not seen there before. Evidently the success that was attending Matt's plans to get away with the air-ship had lifted a grievous load from her spirits.
Walking around the car, Helen picked up the bag which they had taken with them into the swamp.
"This must go with you, Matt," she continued, pushing the bag under the driver's seat, "along with the rest of the stuff piled up on the ground there."
While she was on that side of the car she cast off the mooring-rope and flung it into the air-ship.
Matt dropped the rifle and released the rope on the other side.
The Hawk was now in readiness to take to flight. With nothing to hold it, the gas-bag began to feel the effects of the wind that was blowing and to move about in answer to the faint gusts. But it rode on an even keel, for its buoyancy had to be accelerated by the propeller before it would rise, or could be maneuvered.
The girl had started toward the bags, heaped up on the ground. Before she could reach them, however, a loud yell from the opposite side of the island caused her to halt in consternation.
The clamoring whoops went up from Needham and Grove as they struggled fiercely to free themselves.
Matt, seeing that there was not an instant to be lost, leaped into the car and tilted the steering-rudder at an angle which would carry the air-ship upward.
"Come along!" he shouted to the girl as he started the engine. "Get into the car, Helen!"
"Hurry, hurry!" screamed the girl, running directly away from the car and in the direction of Brady and Pete, who were making for the Hawk at a run.
A pang of regret ran through Matt at the thought of leaving Helen Brady behind to bear the brunt of her father's anger; but there was no time for argument. He started the propeller, and the Hawk began to move up the airy incline toward the tops of the trees that walled in the edge of the "island."
The struggles of Matt's two prisoners became desperately frantic. So violently did they wrestle with their bonds that the car tipped and swayed dangerously. Matt had no time to give to them, just then, being wholly wrapped up in the maneuvering of the Hawk.