"Of course I know that you mean Mr. Livingstone, but I would like to hear your reasons for suspecting him."
"From your account Miss Livingstone suspected some one, and this caused her to be so agitated that she was unaware of the fact that she had changed her seat. Women are shrewd in these affairs, and I was confident that the girl had good reasons for her conduct. It was evident that the person in her mind was either her brother or her sweetheart. I decided between these two men from your account of your interviews with them. Moore impressed you as being honest, and he told you that one of the ladies suspected him. In this he was mistaken, but his speaking to you of it was not the act of a thief. Mr. Livingstone, on the other hand, tried to throw suspicion upon Mr. Gray."
"Of course that was sound reasoning after you had concluded that Mrs. Gray was lying. Now tell me how you recovered the jewel."
"That was easier than I expected. When I got him alone, I simply told Mr. Livingstone what I knew, and asked him to hand me the opal. With a perfectly imperturbable manner, understanding that I promised secrecy, he quietly took it from his pocket and gave it to me, saying:
"Women are very poor conspirators. They are too weak."
"What story did you tell Mr. Gray?"
"Oh, he would not be likely to inquire too closely into what I should tell him. My check was what he most cared for. I told him nothing definitely, but I hinted that his wife had secreted the gem during the darkness, that he might not ask her for it again; and that she had intended to find it again at a future time, just as he had meant to pawn it and then pretend to recover it from the thief by offering a reward."
"One more question. Why did Mr. Livingstone steal it?"
"Ah; the truth about that is another mystery worth probing, and one which I shall make it my business to unravel. I will venture a prophecy. Mr. Livingstone did not steal it at all. Mrs. Gray simply handed it to him in the darkness. There must have been some powerful motive to lead her to such an act; something which she was weighing, and decided impulsively. This brings me to a second point. Livingstone used the word conspirators; that is a clue. You will recall that I told you that this gem is one of a pair of opals, and that with the other, the two would be as interesting as any jewels in the world. If anyone ever owns both it shall be your humble servant, Leroy Mitchel, Jewel Collector."