This was a disappointment to the two lads, who had banked on being aboard the Marie Theresa in her raid. However, orders were not to be disobeyed. Day was breaking when the Austrian cruiser steamed in among the French ships. Jack went aboard the admiral's flagship and reported. It was while he was standing beside the admiral that a fearful commotion broke out on board the captured Austrian cruiser. There was the sound of a big gun, and a shell screamed overhead. "The fools!" exclaimed the admiral. "Can't they understand they have been captured?" Evidently the Austrians could not, for a second shell screamed overhead. Quickly the flagship signaled the French aboard the captured vessel to leave, and when they were over the side and well out of harm's way the French dreadnought opened fire on the cruiser. Men now emerged from below on to the deck of the captured vessel, and rushed rapidly about. An officer leveled a glass and took in the imposing sight of the French gathered about on all sides of him. In another moment a white flag was run up at the masthead. It was the sign of surrender. The French admiral complimented both lads highly on the success of their venture; and congratulated them again personally that night, when the Marie Theresa, after a successful raid into the very midst of the Austrian fleet, returned unscathed--leaving at the bottom of the sea two Austrian torpedo boats. CHAPTER XVIII THE BATTLE IN THE ADRIATIC The French and Austrian fleets were steaming into battle in the Adriatic. This coming struggle, while it was to be by no means decisive, was nevertheless the first engagement of any magnitude to be fought in southern waters; also it was the first in which fighters of the air were to play an important part. The Marie Tieresa, back from her successful raid, was one of the foremost in the French line of battle. Now, as she steamed forward with the rest of the fleet, her hydroplanes were made ready for action. Captain Dreyfuss summoned Jack and Frank before him. "You will each take a seat in one of the hydroplanes," he ordered. "Your duties will be to drop bombs on the enemy. Each machine carries two men, one a pilot. Therefore you will each take separate machines." Frank and Jack saluted, and a moment later were in their places. What was Jack's surprise to find that the pilot of his machine was none other than the French midshipman he had so lately engaged in fistic combat. The latter, whom the boys had learned to call Pierre, greeted him with a smile. "I'm glad I am to have you along," he said simply. "Thanks," was Jack's brief reply. The French hydroplanes, at least fifty of them, from all the battleships, now skimmed over the water, and a moment later soared in the air. Flying on beyond the French ships, a smudge of smoke came into view, then another, and then many more. Ships of all kinds, Jack could see, dreadnoughts, cruisers, torpedo boats and scout ships, advancing toward them.