"Again, they dared not for your sake. You know a great deal, David, but there is darkness and trouble and wickedness yet that I dare not speak of. And you are in danger. Already Reginald Henson has shown you what he can do." "And yet he doesn't know everything," David smiled. "He may have stabbed me in the back, but he is quite ignorant as to what advice I gave to Enid Henson, which brings me back to the cigar-case. You saw me looking at it in Lockhart's. Go on." "Yes, I watched you with a great deal of curiosity. Finally you went off out of the shop saying that you could not afford to buy the cigar-case, and I thought no more of the matter for a time. Then we found out all about your private affairs. Oh, I am ashamed almost to go on." The dainty little face grew crimson; the hand in David's trembled. "But we were desperate. And, after all, we were doing no harm. It was just then that the idea of the cigar-case came into my mind. We knew that if we could get you to take that money it would only be as a loan. I suggested the gift of the case as a memento of the occasion. I purchased that case with my own money and I placed it with its contents on the doorstep of your house." "Did you watch it all the time?" "No, I didn't. But I was satisfied that nobody passed, and I was sufficiently near to hear your door open at the hour appointed. Of course, we had carefully rehearsed the telephone conversation, and I knew exactly what to do." David sat very thoughtfully for some little time. "The case must have been changed," he said. "It is very difficult to say how, but there is no other logical solution of the matter. At about half-past twelve on that eventful night you placed on my doorstep a gun-metal cigar-case, mounted in diamonds, that you had purchased from Lockhart's?" "Yes, and the very one that you admired. Of that I am certain." "Very well. I take that case with me to 218, Brunswick Square, and I bring it back again. Did I take it with me or not? Anyhow, it was found on the floor beside the body. It never passed out of my possession to my knowledge. Next day I leave it at the office of Messrs. Mossa and Mack, and it gets into the hands of the police." "Was it not possibly changed there, David?" "No, because of the initials I had scratched inside it. And beyond all question that case--the same case, mind you, that I picked up on my doorstep--was purchased by the man now lying in the hospital here from Walen's, in West Street. Now, how was the change made?" "If I could only see my way to help you!" "The change was made the day you bought the case. By the way, what time was it?" "I can't tell you the exact time," Ruth replied. "It was on the morning of the night of your adventure." "And you kept it by you all the time."