“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?”
“Doubtless,” replied Rouletabille, who had taken the hand of the Lady in Black in both his own as though he wished to give her courage, “he must have believed that it was yourself.”
“That then explains the fact that when I reached my door I had only to push it open. Pere Bernier believed that I was within.”
“Exactly: that is good reasoning!” declared Rouletabille. “And Pere Bernier, who had opened to Darzac No. 1, had not troubled himself about No. 2, since he did not see him any more than yourself. You certainly reached the Square Tower at the moment that Sainclair and myself called Bernier to the parapet to see whether he could help us in understanding the strange gesticulations of Old Bob, talking at the threshold of the Barma Grande to Mrs. Rance and Prince Galitch.”
“But Mere Bernier!” cried M. Darzac. “She had gone into her lodge. Was she not astonished to see M. Darzac come in a second time when she had not seen him go out?”