The dot in the sky ahead grew in size and took on the shape of an airplane. Tim was flying high and there was little chance that McDowell would see them until they were on top of him. The flying reporter's thoughts went back to Atkinson. He wondered about Ralph and the wound on his head, and there was no mercy in his heart as he guided the Jupiter on the now relentless chase after the fleeing McDowell. The outline of the old biplane grew larger and larger as the fast-flying Jupiter cut down the distance. Tim had planned a new campaign of action. In the Jupiter, knowing every movement and capability of the ship, he felt confident that he could ride McDowell into the ground, out-maneuver and out-speed him until the other would welcome the chance to fight it out below. The Jupiter was flying a thousand feet above the old trainer when Tim dropped the nose down and opened the throttle for a power dive. As they swooped down, he saw McDowell look up, saw the surprise and alarm on the other's face. Then they were by with less than ten feet to spare between the ships. Tim climbed the Jupiter dizzily until he was back on McDowell's tail, riding it hard and close. The flyer ahead emptied another magazine at them and then threw his automatic away in disgust. He was out of ammunition. Now it was a case of plane against plane, pilot against pilot, and nerve pitted against nerve for Prentiss was unable to shoot now. Closer and closer Tim drove the Jupiter. He was just above and behind the biplane, riding it down, relentlessly and with grim intent. McDowell twisted and turned, but always the cream and green biplane rode his tail. He dodged to the right and then to the left, looped, barrel-rolled, but it was all in vain. Tim guessed his every maneuver and went him one better. "Country's getting rougher," cried Prentiss. "Bad place for a forced landing," agreed Tim. They were flying at a little under 3,000 feet and Tim was riding McDowell's plane down, foot by foot. It was a slow and nerve-wracking process but it seemed destined for success. Once in a while he would veer his ship enough to let Prentiss get in a shot, but none of them found their mark. The air was getting rougher. Even the steady, easy-flying Jupiter was rocking and pitching and Tim could see that the old biplane ahead of them was bucking hard. Prentiss turned around. "Look at the biplane's wings," he cried. Tim watched closely. The wings were flapping, threatening to break loose from the ship at any moment. The chase was nearly over. McDowell would be forced down. Tim glanced at the country below. It was rough and broken, almost impossible for a safe landing. A startled cry from Prentiss drew his attention back to the biplane. The old ship was breaking up! McDowell had been pushing it too hard, the spins and rolls and loops had been more than the ancient spruce could stand. The right wing was giving way, the top section drooping down in the lower one.