Chapter XII. In Deep Waters

Mary Nestor, as well as Tom Swift, felt great alarm over the condition of Mr. Keith. But the nurse, after reviving him, said:

"He is in no special immediate danger. Talking about his trouble overstrained him, but in the end it may do him good."

"Then will he get well?" asked Mary.

"He may," was the noncommittal answer. "His recovery would be hastened, however, if his mind could be relieved. He keeps worrying about the loss of his papers that proved his share in the Texas oil wells. Until they can be given back to him he is bound to suffer mentally, and of course that effects him physically."

"Oh, if we only could do something!" murmured Mary.

"Perhaps we can," said Tom in a low voice. "I've learned something these last few hours. I don't want to promise too much, but I think I begin to see how matters lie. There, he's rousing. Speak to him, Mary."

Mr. Keith opened his eyes, and smiled at his niece.

"Did I dream it," he asked in a low voice, "or was there some young man with you, Mary, my dear, to whom I was telling my troubles about the oil-well papers?"

"You didn't dream it, Uncle," Mary answered. "You were talking to Tom Swift. Here he is," and Tom came forward.

"Oh, yes, I remember now," said Mr. Keith passing his hand wearily over his eyes. "I thought, for a moment, that he had recovered my papers for me. But that was a dream, I'm sure."

"It may not be, Mr. Keith!" exclaimed Tom.

"May not be? What do you mean?"

"I mean," replied the young inventor, "that I am much interested in what you have told me. Now that I have proved that the Dixwell Hardley who is to sail with me is the same one who has treated you so shabbily, I think I understand the truth. I don't want to make a promise that I may not be able to carry out, but I am going to watch this man while he's on the submarine with me."

"Then you are going on with the voyage, Tom?" asked Mary.

"I shall have to," he said. "I have entered into an agreement with this man and I'm not going to break my contract, no matter what he does. But I think I know what his game is. Mr. Keith, I'm going to ask you to keep quiet about this matter until I come back from the treasure search. I may then have some news for you."

"I hope you do, young man, I hope you do!" exclaimed the oil contractor, with more energy than he had previously shown. "It means a lot, at my age, to lose a small fortune. If I were well and strong I'd tackle this Dixwell Hardley myself, and make him give up the papers I'm sure he has hidden away. He has them, I'm positive."

"Well, he may not have them, but perhaps he knows where they