The pilot of the German craft was caught off his guard. He dashed upon the hydroplane. But as he neared it he swerved to the left to avoid a collision. It was what Jack had expected. Standing up in his precarious position, Jack took a snap shot at the pilot as the German craft swept by. At that close distance, in spite of the rate of speed at which the enemy was travelling, a miss was practically impossible. The German machine swayed crazily from one side to the other; then dived. "I got him, Frank!" shouted Jack. Both lads gazed over the side at the falling enemy. Suddenly the machine righted and descended more slowly. "By Jove! a cool customer," said Frank. "He's regained control of the plane. He'll be up again in a moment." Again they watched the foe carefully. "No, he won't," said Jack, "he's still going down." "Then we may as well be moving," said Frank. "Hold on!" shouted Jack. "We can't leave those fellows there. They may get to shore or be picked up. Then they would give the warning and all our efforts would be for naught." "Right," said Frank. "We'll go down after them." The hydroplane descended slowly. CHAPTER X THE FIGHT ON THE WATER Below, the fallen aeroplane rested upon the surface of the sea. In the darkness, it was hard for the lads to tell just how badly the craft was damaged and whether it would float; but Jack's idea was to be on the safe side. While still some distance from the water, there was a shot from below. "Hello!" said Jack. "They're alive and kicking, all right. Wonder if we can't go down and get them from the water." "It's a better plan, I guess," said Frank. "We'll have an even break then. This way they have all the advantage." He opened up the engine and the hydroplane ran some distance from the position of the men below. Then he shut off the motor and allowed the plane to glide down to the sea. With the craft riding the swell of the waves, Jack picked up the enemy with his night glass. The disabled craft also was riding the waves gently perhaps five hundred yards away. Jack gave the position to Frank, and the hydroplane approached the foe slowly. Within a range that would make accurate revolver shooting possible, the hydroplane came to a halt. As it did so there was the sound of a revolver shot from across the water and something whizzed overhead. "Must have some pretty fair shooters over there," said Frank, quietly. "However, they can't see us any better than we can see them. Of course, they can see our craft all right, the same as we can see theirs, but they can't spot us." "No; nor we can't spot them, which makes it worse," said Jack. "We'll try a couple of shots for luck," said Frank. He raised his revolver and fired quickly twice. His efforts were rewarded by a scream, apparently of pain. "Must have hit one of them," he said grimly. Again a revolver across the water flashed and the two lads heard a bullet whistle by. Jack fired but without result and then Frank fired again.