The German leader had recovered consciousness, and springing to his feet, dashed to the water's edge and fired point blank at the machine. Fortunately, in his excitement his aim was poor and he missed. Before he could fire again, Frank wheeled about and his revolver spoke sharply. The German threw up his arms, and with a gasp, pitched headlong into the sea. But the sounds of the two shots had aroused the sleeping camp. Wild cries came from the shore, followed by heavy footfalls as the Germans rushed toward the water. "Hurry, Frank!" cried Jack. As lightly as a fairy the hydroplane skimmed over the water; then went soaring in the air. Frank gave a loud cheer. "Safe!" he exclaimed. But the lad was wrong. From on shore came a chorus of angry cries and imprecations. Hastily the Germans made a rush for their aeroplanes to give chase. None would move. Followed more cries and angry shouts. "Wait," said one German. "I've some gasoline." Rapidly he opened up a big can, which he took from the bottom of his machine. Quickly the tank was filled and the man climbed into the pilot's seat. Another jumped in with him. "Give us some of that gasoline!" cried another. The German shook his head. "Not enough," he replied. "We'll overtake those fellows and then come back for the rest of you." The aeroplane leaped skyward and started in pursuit of Frank and Jack. The two boys, believing that they were safe, were going along only at a fair rate of speed when Jack's keen ears caught the sound of the pursuing machine. "They're after us, Frank!" he called. "Impossible!" replied Frank. "How can they fly without gas?" "Well, they're coming, all the same," declared Jack. He produced his two revolvers and examined them carefully. "You run this thing and I'll do what fighting is necessary," he said. "Wish I could shoot like you can; but I can't; and I can't run this machine either." The German aeroplane was gaining steadily. "He can outrun us," said Frank, quietly. "There is only one, thank goodness. You'll have to bring him down, Jack." "I'll try," was Jack's reply. "If I had a rifle I might be able to pick him off now." "Well, he won't hardly have any the best of it," said Frank. "The chances are he has no rifle either." Frank was correct in this surmise. Rapidly the German aircraft gained. "Crack!" the German had fired the first shot. It went wild. Jack fired, but with no better result. "Hit anything?" asked Frank, without turning his head. "No," said Jack, "but neither did the other fellow." "Try it again," said Frank. Jack did so; but again the bullet went wild. All this time the two craft were flying straight out to sea. Once more the German fired and Jack felt something whizz overhead. "This is getting too close," the lad muttered to himself. Then he called to Frank. "Slow down, quick!" Frank had no means of telling what plan Jack had in mind, but he did not hesitate. The hydroplane slowed down with a jerk.