But there was no time to watch the Iron Mate now. Tim concentrated on the task of bringing down the other plane. Ahead of him, Pat crouched in the cockpit, the machine gun ready. The seaplane was making a desperate attempt to get under the shelter of the _Iron Mate_ but Tim drove on relentlessly on the tail of the other ship. There was no chance for the pilot to land and taxi back to the steamer. The Sea King was fast and easy to handle. In less than two minutes Tim had overhauled the bombing plane and Pat, sighting with a steady hand, pulled gently on the trigger of the light machine gun. It chattered and jumped, but he got his aim again and poured a stream of bullets at the target ahead. Tim, watching intently and matching every move of the fleeing pilot, saw the bullets ripping into the wings. Then Pat got the range on the fuselage and the line of bullets crept nearer and nearer the cockpit. Sensing that death was near, the pilot tried to loop and get onto the tail of Tim's plane, but the flying reporter guessed the maneuver almost before it started and he placed Pat in a position to pour a stream of bullets into the motor of the other plane. Suddenly there was only the sound of their own motor. The other seaplane was falling away with its prop turning idly. Pat, thoroughly angered at the attempt to sink the _S-18_ with a bomb, trained his gun on the other pilot but Tim pulled the nose of the Sea King up and spoiled his aim. "He's all through," he shouted. "They'll never be able to repair that motor." Spread out below them was a strange panorama. Against the green background of the Isle of the Singing Trees the _S-18_ was throwing shell after shell at the _Iron Mate_, and the tramp steamer was responding. One good, solid shot would sink the _S-18_, while the _Iron Mate_ could stand a lot of shelling without going down. Tim noticed that the _S-18_ was moving slowly back and forth behind the reef and that the submarine was ready to submerge at a moment's notice. Only Gunner Joe and the men he had selected to help him load the gun were on deck. "Joe's using a lot of ammunition," cried Pat. "He'd better get a direct aim soon or they'll get us after all." A white line of bubbles streaked the water. "Joe's fired his torpedo!" cried Pat. A lookout on the _Iron Mate_ saw the torpedo and the old tramp swung its stern into the clear just in time. The torpedo streaked on out to sea. Tim's attention shifted back to the pilot of the crippled seaplane. It was landing at least a mile away from the _Iron Mate_ and he admired the cool nerve of the other pilot, who brought his craft down to a safe landing. With motor dead, the flyer would have to wait for a boat from the _Iron Mate_ to pick him up. Tim sent the Sea King into a dive while Pat shouted questions at him, landed and taxied alongside the disabled plane.