All that Whitney said we now knew to be true.

“She has one interesting dilemma, however, which I do not mind telling you,” remarked Kennedy at length.  “She cannot expect me to keep secret what she said before all of us.  Inez Mendoza would mention it, anyhow.”

“What was that?” queried Whitney, dissembling his interest.

“Why,” replied Kennedy slowly, “it was that, with the plans for digging for the treasure which you say you have, suppose you and Lockwood and your associates have not the dagger—­how are you better off than previous hunters?  And supposing you have it—­what does that imply?”

Whitney thought a moment over the last proposition of the dilemma.  “Imply?” he repeated slowly.  Then the significance of it seemed to dawn on him, the possession of the dagger and its implication in regard to the murder of Mendoza.  “Well,” he answered, “we haven’t the dagger.  You know that.  But, on the other hand, we think our plans for getting at the treasure are better than any one else has ever had, more certain of success.”

“Yet the possession of the dagger, with its inscription, is the only thing that absolutely insures success,” observed Kennedy.

“That’s true enough,” agreed Whitney.  “Confound that man Norton.  How could he be such a boob as to let the chance slip through his fingers?”

“He never told you of it?” asked Kennedy.

“Yes, he told me of the dagger, but hadn’t read the inscription, he said,” answered Whitney.  “I was so busy at the time with Lockwood and Mendoza, who had the concession to dig for the treasure, that I didn’t pay much attention to what Norton brought back.  I thought that could wait until Lockwood had been persuaded to join the interests I represent.”

“Did Lockwood or Mendoza know about the dagger and its importance?” suggested Craig.

“If they did, they never said anything about it,” returned Whitney promptly.  “Mendoza is dead.  Lockwood tells me he knew nothing about it until very lately—­since the murder, I suppose.”

“You suppose?” persisted Kennedy.  “Are you sure that he knew nothing about it before?”

“No,” confessed Whitney, “I’m not sure.  Only I say that he told me nothing of it.”

“Then he might have known?”

“Might have.  But I don’t think it very probable.”

Whitney seemed to be turning something over in his mind.  Suddenly he brought his fist down on the little round table before us, rattling the glasses.

“Do you know,” he exclaimed, “the more I think about it, the more convinced I am that Norton ought to be held to account for that loss!  He ought to have known.  Then the presumption is that he did know.  By heaven, I’m going to have that fellow watched.  I’m going to do it to-day, too.  I don’t trust him.  He shall not double-cross me—­even if that woman does!”

I wondered whether Whitney was bluffing.  If he was, he was making a lot of fuss over it.  He talked more and more wildly, as he grew more excited over his latest idea.