“What happened to you?”

“And what happened to you? Did the Sherman sink?”

It was Ned who asked the first question, Jerry who propounded the second. And then he and Ned and Bob clasped hands while about them stood a circle of cheering sailors and soldiers on board the war vessel.

A boat had been sent to bring the refugees from the Altaire, and when Jerry and his chums were safe on board and the cruiser had moved sufficiently far away to be out of danger, the derelict was blown up. Afloat she would be a constant menace to navigation, and it was impossible to salvage her.

It was following this necessary destruction of what had once been a fine vessel that Ned and Jerry questioned one another.

Then came explanations. Jerry told how he had managed to get aboard the derelict, and how[238] he had been joined by Bob, the professor, and Judd. And, in his turn, Ned described the life aboard the transport, his talk with Dr. Hallet, and their transfer to the warship.

“Where is Dr. Hallet now?” asked Jerry.

“He’s shut up in his cabin, I imagine,” answered Ned. “Somehow, he managed to get a cabin to himself. He seems to avoid me. I declare I don’t know what it all means.”

At that moment a steward approached Professor Snodgrass, who was standing in the group that included Ned, Bob and Jerry.

“Dr. Hallet wishes to see you,” the steward said to Professor Snodgrass. “He has heard of your rescue.”

“Wishes to see me!” exclaimed the little scientist. “Dear me, this is rather extraordinary! I don’t know whether to see him or not!”

“The surgeon told me to tell you, sir,” added the steward, “that Dr. Hallet is perfectly normal again. All his trouble has gone, and he is himself once more.”

“Oh, in that case of course I’ll see him!” exclaimed the professor. “It’s all right, boys!” he added to Bob and Jerry. “He must have had the necessary shock to bring back his reason. I hope it will never leave him again. I’ll go to see him at once. I am rejoiced to hear this good news!”

As the professor hurried away Ned looked curiously[239] at his two chums. Then he began to question them.

“Say, what’s it all about?” he asked. “What does the professor mean when he says Dr. Hallet has recovered his reason? Has he been crazy?” burst out Ned.

“Practically so, yes, though harmless,” said Jerry. “The professor explained everything to us while we were on the Altaire. Did you begin to suspect anything?”

“I didn’t know what to think, nor what to expect or suspect,” answered Ned. “At one time Dr. Hallet seemed about to tell me everything, and explain a lot of queer circumstances. Then something happened—I think it was when our wireless got to working—and there was too much excitement to think of anything but a rescue. Since we’ve been on this warship the doctor has avoided me. I declare I didn’t know what to think.”

“Nor did we until the professor explained,” said Jerry. “It seems we were all wrong in our conjectures, but it wasn’t exactly our fault, for the doctor’s trouble made him irresponsible.”

“Does that account for his talk against the professor in the restaurant, and why he had a guard at his cabin?” asked Ned.

“Yes,” was the answer from Bob, while Jerry said:

“I’ll tell you the yarn, Ned. All our troubles[240] are over now, I hope. We had enough of them while they lasted, and at one time it seemed as if we were all booked for Davy Jones’ locker. But here we are, and we’ll soon be back home where we can live life as it ought to be lived.”

“We’ll have our meals on time, for one thing,” declared Bob.

“And the folks will be glad to see us,” added Jerry.

“And perhaps some others than just our folks,” put in Ned, with a smile. He was thinking of girls, and, perchance, one in particular.

The story Jerry told, having had it from Professor Snodgrass, was to the effect that Dr. Hallet had once been a colleague of the little scientist with whom the Motor Boys had made so many trips. When the war broke out and Professor Snodgrass went to Europe to study the effect of battle noises on certain insects, Dr. Hallet made a like voyage to take up another branch of science. In some lines he and Professor Snodgrass were associated, working to the same end. In other lines they differed radically, and often violently, though they were always good friends and helped one another.

Dr. Hallet went too near the front toward the close of the war, and was under fire. He suffered from shell shock, which affected his mind, and among his hallucinations was one in which he[241] imagined that Professor Snodgrass was his enemy and was trying to obtain a certain scientific secret from him.

In order to effect, if possible, a cure of his friend, Professor Snodgrass, on the advice of the physicians treating Dr. Hallet, did not dispute this false idea. On the contrary he even encouraged it. The state of mind of the doctor accounted for his violent talk against the professor in the restaurant, and his queer actions led Marie, the pretty waitress, to give the queer scientist the name of “le cochon.” Of course that was not deserved.

“Did Dr. Hallet try to blow up the ship?” asked Ned.

“Of course not!” exclaimed Jerry. “That time we met him with the black box he imagined he was concealing some insects from the gaze of Professor Snodgrass, and also from us. He included us in his fear, it seems. There never was a bomb on the ship. All the accidents were due to defects in the machinery—the bursting of steam pipes and the like.”

“Yes, I’ve since heard that,” Ned admitted. “But I didn’t know whether or not Dr. Hallet might not have tried to set off a bomb.”

“Nothing like it!” laughed Jerry. “We were all wrong in thinking him that sort of man. He did act queerly, but it was because he was suffering[242] from shell shock. And he made such a fuss about the chance that Professor Snodgrass might steal some scientific secrets that Captain M............