“Yes, but Mirsky came half an hour after they were—­Oh, yes, I see.  What a fool I was!  I was forgetting.  Of course, when I first missed the tracings, they were in this walking-stick, safe enough, and I was tearing my hair out within arm’s reach of them!”

“Precisely.  And Mirsky took them away before your very eyes.  I expect Ritter was in a rare funk when he found that the drawings were missed.  He calculated, no doubt, on your not wanting them for the hour or two they would be out of the office.”

“How lucky that it struck me to jot a pencil-note on one of them!  I might easily have made my note somewhere else, and then I should never have known that they had been away.”

“Yes, they didn’t give you any too much time to miss them.  Well, I think the rest pretty clear.  I brought the tracings in here, screwed up the sham stick and put it back.  You identified the tracings and found none missing, and then my course was pretty clear, though it looked difficult.  I knew you would be very naturally indignant with Ritter, so, as I wanted to manage him myself, I told you nothing of what he had actually done, for fear that, in your agitated state, you might burst out with something that would spoil my game.  To Ritter I pretended to know nothing of the return of the drawings or how they had been stolen—­the only things I did know with certainty.  But I did pretend to know all about Mirsky—­or Hunter—­when, as a matter of fact, I knew nothing at all, except that he probably went under more than one name.  That put Ritter into my hands completely.  When he found the game was up, he began with a lying confession.  Believing that the tracings were still in the stick and that we knew nothing of their return, he said that they had not been away, and that he would fetch them—­as I had expected he would.  I let him go for them alone, and, when he returned, utterly broken up by the discovery that they were not there, I had him altogether at my mercy.  You see, if he had known that the drawings were all the time behind your book-case, he might have brazened it out, sworn that the drawings had been there all the time, and we could have done nothing with him.  We couldn’t have sufficiently frightened him by a threat of prosecution for theft, because there the things were in your possession, to his knowledge.

“As it was he answered the helm capitally:  gave us Mirsky’s address on the envelope, and wrote the letter that was to have got him out of the way while I committed burglary, if that disgraceful expedient had not been rendered unnecessary.  On the whole, the case has gone very well.”

“It has gone marvelously well, thanks to yourself.  But what shall I do with Ritter?”

“Here’s his stick—­knock him down-stairs with it, if you like.  I should keep the tube, if I were you, as a memento.  I don’t suppose the respectable Mirsky will ever call to ask for it.  But I should certainly kick Ritter out of doors—­or out of window, if you like—­without delay.”