* * * * * First of all, he investigated to make sure that the bolts of the door behind him were closely drawn; then, returning to the table, he took up a compass. “I have the intention of making my demonstration,” he said, “along the same lines on which the ‘body too many’ has produced itself. It will be, thereby, only the more irrefutable.” And, with his compass, he took, upon M. Darzac’s drawing, the measure of the radius of the circle which represented the space occupied by the Tower of the Bold, so that he was immediately afterward able to trace the same circle upon an immaculate piece of white paper which he had fastened with copper-headed nails to another drawing board. When the circle was traced, Rouletabille, putting down his compass, picked up the tiny dish of red paint and asked M. Darzac whether he recognized it as the coloring matter he had used. M. Darzac, who, from all appearances, understood the significance of the young man’s words and actions no better than the rest of us, replied that, to the best of his belief, it was the same paint which he had mixed for his wash drawing. A good half of the paint had dried up in the bottom of the dish, but, according to the opinion expressed by M. Darzac, the part which remained would, upon paper, give nearly the same tint with which he had “washed” the drawing of the peninsula of Hercules. “No one has touched it,” said Rouletabille very gravely, “and nothing has been added to it, save a single tear. Besides, you will see that a tear more or less in the paint cup would detract nothing from the value of my demonstration.” Thus saying, he dipped the brush in the paint and began carefully to “wash” all the space occupied by the circle which he had previously traced. He did this with the care and exactitude which had already astonished me in the Tower of the Bold when I had been nearly stupefied in seeing him absorbed in a drawing when we knew that someone had been assassinated. When he had finished he looked at his immense silver watch and said: “You may see, ladies and gentlemen, that the coating of paint which covers my circle is neither more nor less thick than that which covers the circle of M. Darzac. It is almost the same thing--the same tint.” “Undoubtedly,” rejoined M. Darzac. “But what does all this signify?” “Wait!” replied the reporter. “It is understood, then, that it is you who have made this plan and this painting?” “I was certainly in enough of an ill humor when I found the state it was in that time I went with you into Old Bob’s cabinet when we came out of the Square Tower. Old Bob had ruined my drawing by letting his skull roll over it.” “We are there!” spoke up Rouletabille, quick as a flash. And he lifted from the bureau the “oldest skull of the human race.” He turned it over and showed the crimsoned jaws to M. Darzac. Then he inquired: