"'Who are you, there, inside?' Mirsky shouted indignantly from the landing. 'Why for you go in my room like that? Open this door at once, or I call the police!' "I took no notice. I had got the full number of negatives, one for each drawing, but I was not by any means sure that he had not taken an extra set; so I went on hunting down the rack. There were no more, so I set to work to turn out all the undeveloped plates. It was quite possible, you see, that the other set, if it existed, had not yet been developed. [Illustration: "I HAVE CALLED TO SEE M. MIRSKY."] "Mirsky changed his tune. After a little more banging and shouting, I could hear him kneel down and try the keyhole. I had left the key there, so that he could see nothing. But he began talking softly and rapidly through the hole in a foreign language. I did not know it in the least, but I believe it was Russian. What had led him to believe I understood Russian I could not at the time imagine, though I have a notion now. I went on ruining his stock of plates. I found several boxes, apparently of new plates, but, as there was no means of telling whether they were really unused or were merely undeveloped, but with the chemical impress of your drawings on them, I dragged every one ruthlessly from its hiding-place and laid it out in the full glare of the sunlight--destroying it thereby, of course, whether it was unused or not. "Mirsky left off talking, and I heard him quietly sneaking off. Perhaps his conscience was not sufficiently clear to warrant an appeal to the police, but it seemed to me rather probable at the time that that was what he was going for. So I hurried on with my work. I found three dark slides--the parts that carry the plates in the back of the camera, you know--one of them fixed in the camera itself. These I opened, and exposed the plates to ruination as before. I suppose nobody ever did so much devastation in a photographic studio in ten minutes as I managed. "I had spoilt every plate I could find and had the developed negatives safely in my pocket, when I happened to glance at a porcelain washing-well under the sink. There was one negative in that, and I took it up. It was _not_ a negative of a drawing of yours, but of a Russian twenty-rouble note! [Illustration: "HE BEGAN TALKING SOFTLY AND RAPIDLY."] "This _was_ a discovery. The only possible reason any man could have for photographing a bank-note was the manufacture of an etched plate for the production of forged copies. I was almost as pleased as I had been at the discovery of _your_ negatives. He might bring the police now as soon as he liked; I could turn the tables on him completely. I began to hunt about for anything else relating to this negative.