It was soon done. The paint disappeared. He made us bear witness to the fact. Then, placing himself in front of the bureau, he stood in mute contemplation before his own drawing. This lasted for ten minutes, during which he had, by a sign, ordered us to keep silence--ten minutes which seemed as long as the same number of hours. What was he waiting for? What did he expect? Suddenly, he seized the skull in his right hand, and with the gesture familiar to those who play at bowling, he tossed it about so that it rolled hither and yon over the drawing; then he showed us the skull and bade us notice that it bore no trace of red paint. Rouletabille drew out his watch again. “The paint has dried upon the plan,” he said. “It has taken a quarter of an hour to dry. Upon the 11th of April we saw at five o’clock in the afternoon, M. Darzac entering the Square Tower and coming from out of doors. But M. Darzac, after having entered the Square Tower, and after having fastened behind him the bolts of his door, as he tells us, has not gone out again until we came to fetch him after six o’clock. As to Old Bob, we had seen him enter the Square Tower at six o’clock and there was no paint on this skull then! “_How was this paint which has taken only a quarter of an hour to dry upon this plan, fresh enough still--more than an hour after M. Darzac had left it--to stain Old Bob’s skull when the savant, with a movement of anger, threw it down on the plan as he entered the Round Tower?_ There is only one explanation of this, and I defy you to find another--and that is that _the Robert Darzac who entered the Square Tower at five o’clock and whom no one has seen going out again, was not the same as the one who came to paint in the Round Tower before the arrival of Old Bob at six o’clock and whom we found in the room in the Square Tower without having seen him enter there and with whom we went out. In one word--he was not the same man as the M. Darzac here present before us. The testimony of pure reason shows that there are two personalities appearing in the guise of Robert Darzac!_” And Rouletabille turned his eyes full upon the man whose name he had uttered. Darzac, like all the rest of us, was under the spell of the luminous demonstration of the young reporter. We were all divided between a new horror and a boundless admiration. How clear was every word that Rouletabille had uttered! How clear--and how terrible! Here again we found the mark of his prodigious and logical mathematical intelligence! M. Darzac cried out: “It was thus, then, that _he_ was able to enter the Square Tower under a disguise which made him, without doubt, my very image! It was thus that he was able to hide behind the panel in such a way that I did not see him myself when I came here to write my letters after quitting the Tower of the Bold, where I left my drawing. But how could Pere Bernier have opened to him?”