The air gun boomed. At the same moment a man was seen to lean over the side of the Zeppelin. He dropped something. Again Captain Raleigh acted promptly and brought the head of the _Queen Mary_ around. The German bomb missed. Before another could be dropped, the man who manned the anti-aircraft gun fired again. Another cheer from the crew. The Zeppelin began to sink slowly. "Full speed ahead!" cried Captain Raleigh. "They'll sink us!" The _Queen Mary_ leaped ahead just in time. And then the Zeppelin dropped. With a splash it hit the water perhaps a quarter of a mile from the British battleship. Came cries from the men, caught beneath the gas bag. At that moment Jack stood close to the bridge. Captain Raleigh saw him. "Man a boat, Mr. Templeton," he called, "and rescue those fellows in the water." Quickly Jack sprang to obey. Frank leaped after him. Hurriedly a small boat was gotten out and launched. A half dozen sailors sprang in and took up the oars. Frank and Jack leaped in after them. The oars glistened in the glare of the searchlight as the men raised them and awaited the word. "Give way," said Jack. The boat sped over the smooth surface of the sea. Close to the wreckage of the Zeppelin it approached; and cries told Jack that some of the Germans still lived. "Hurry!" he cried, and the men increased their stroke. Near the wreckage Jack gave the command to cease rowing. A German swam toward the boat. Hands helped him in and he lay in the bottom panting. Other forms swam toward them. These, too, were lifted in the boat. And at last Jack counted fifteen Germans who had been saved. "Are you all here?" he asked of a German officer. "All but Commander Butz, sir," was the man's reply. Jack commanded his men to row closer to the wreckage. "Ahoy there!" he shouted, when he had come close. The lad thought he heard a muffled answer, but he could not make sure. He called again. This time the answer came plainer. "Where are you?" asked Jack. "Under the wreckage," was the reply. Jack scrutinized the wreckage closely. "Looks like it might sink any minute," he said "But we can't leave him there." "What are you going to do?" asked Frank. For answer Jack arose in the boat. Quickly he threw off his coat and kicked off his shoes. Then he poised himself on the edge of the boat. "I'm going after him," he replied. Before Frank could reply, he had dived head first into the sea. With a cry of alarm, Frank also sprang to his feet and divested himself of his coat and shoes. "Stay close, men!" he commanded. "I'll lend a hand if it's needed." He, too, leaped into the water. Rapidly, Jack swam close to the wreckage. He continued to call to the German, and while he received an answer each time, he could not locate the man. Twice he swam around all that remained of the huge Zeppelin. By this time Frank had come up with him. "Can't you find him?" he asked.