The Puzzle Lock

He ran his finger down the list of names and had just turned to the account of one of the customers when we were startled by a loud click from the direction of the strong-room. We both turned sharply and beheld Thorndyke grasping the handle of the strong room door, and I saw with amazement that the door was now slightly ajar. ldquo;God!rdquo; exclaimed Miller, shutting the ledger and starting forward, ldquo;hes got it open!rdquo; He strode over to the door, and directing an eager look at the indicator of the lock, burst into a laugh. ldquo;Well, Im hanged!rdquo; he exclaimed. ldquo;Why, it was unlocked all the time! To think that none of us had the sense to tug the handle! But isnt it just like old Luttrell to have a fools answer like that to the blessed puzzle!rdquo; I looked at the indicator, not a little astonished to observe the row of fifteen As, which apparently formed the key combination. It may have been a very amusing joke on Mr. Luttrells part, but it did not look very secure. Thorndyke regarded us with an inscrutable glance and still grasped the handle, holding the door a bare half-inch open.