Ruth looked relieved. Her pretty features relaxed into a smile.
"Then I fancy Reginald Henson has done so," she said. "I fancy I have solved the mystery of the cigar-case—I mean, the mystery of the one I bought."
"And which was changed for the one purchased at Walen's, hence these tears. But Lockharts say that our case was really purchased by an American."
"Yes, I know. And I fancy that the manager honestly thought so. But I think I can explain that."
It was David's turn to look up eagerly.
"Do you mean it?" he exclaimed. "It will make a wonderful difference if you can. That has been one of the most bewildering knots of the whole puzzle. If we could only trace the numbers of those notes, I suppose changed at the same time as the cigar-case."
"Indeed they were not," Ruth cried. "I have ascertained that the case was changed by Henson, as you and I have already decided. Henson made the exchange not at the time we thought."
"Not when you left the package on the table for him to see?"
"No; at least I can't say. He had the other case then, probably, passed on to him by Van Sneck. Or perhaps he merely ascertained what I had purchased. That was sufficient for his purpose. Of course he must have found out all about our scheme. After I had laid my cigar-case on your doorstep a man quietly changed it for the other purchased at Walen's. But this is the alternate theory only. Any way, I am absolutely certain that you got exactly the same notes that we had placed in the original case."
"That might be," David said, thoughtfully. "But that does not explain the fact that Lockhart's sold your case to an American at the Metropole."