its nail before shooting and then put it back on the nail after shooting?"
"Yes, yes," agreed M. Paul. Already he was far away on a new line of thought, while the other was still grappling with his first surprise.
"Then this murderer must have known that the billiard player was going to bore these holes," went on Papa Tignol half to himself. "He must have been waiting in Number Seven, he must have stood there with his pistol ready while the holes were coming through, he must have let Martinez finish one hole and then bore the other, he must have kept Number Seven dark so they couldn't see him——"
"A good point, that," approved Coquenil, paying attention. "He certainly kept Number Seven dark."
"And he probably looked into Number Six through the first hole while Martinez was boring the second. I suppose you can tell which of the two holes was bored first?" chuckled Tignol.
M. Paul started, paused in a flash of thought, and then, with sudden eagerness: "I see, that's it!"
"What's it?" gasped the other.
"He bored this hole first," said Coquenil rapidly, "it's the right-hand one when you're in this room, the left-hand one when you're in Number Seven. As you say, the murderer looked through the first hole while he waited for the second to be bored; so, naturally, he fired through the hole where his eye was. That was his first great mistake."
Tignol screwed up his face in perplexity. "What difference does it make which hole the man fired through so long as he shot straight and got away?"
"What difference? Just this difference, that, by firing through the left-hand hole, he has given us precious evidence, against him."
"How?"
"Come back into the other room and I'll show you." And, when they had returned to Number Seven, he continued: "Take the pistol. Pretend you are the murderer. You've been waiting your moment, holding your breath on one side of the wall while the auger grinds through from the other. The first hole is finished. You see the point of the auger as it comes through the second, now the wood breaks and a length of turning steel shoves toward you. You grip your pistol and look through the left-hand hole, you see the woman holding back the curtains, you see Martinez draw out the auger from the right-hand hole and lay it down. Now he leans forward, pressing his face to the completed eyeholes, you see the whites of his eyes, not three inches away. Quick! Pistol up! Ready to fire! No, no, through the left-hand hole where he fired."
"Sacré matin!" muttered Tignol, "it's awkward aiming through this left-hand hole."
"Ah!" said the detective. "Why is it awkward?"
"Because it's too near the sideboard. I can't get my eye there to sight along the pistol barrel."
"You mean your right eye?"
"Of course."
"Could you get your left eye there?"
"Yes, but if I aimed with my left eye I'd have to fire with my left hand and I couldn't hit a cow that way."
Coquenil looked at Tignol steadily. "You could if you were a left-handed man."
"You mean to say—" The other stared.
"I mean to say that this man, at a critical moment, fired through that awkward hole near the sideboard when he might just as well have fired through the other hole away from the sideboard. Which shows that it was an easy and natural thing for him to do, consequently——"
"Consequently," exulted the old man, "we've got to look for a left-handed murderer, is that it?"
"What do you think?" smiled the detective.
Papa Tignol paused, and then, bobbing his head in comical seriousness: "I think, if I were this man, I'd sooner have the devil after me than Paul Coquenil."
Chapter IX.
Coquenil Marks His Man
It was nearly four o'clock when Coquenil left the Ansonia and started up the Champs Elysées, breathing deep of the early morning air. The night was still dark, although day was breaking in the east. And what a night it had been! How much had happened since he walked with his dog to Notre-Dame the evening before! Here was the whole course of his life changed, yes, and his prospects put in jeopardy by this extraordinary decision. How could he explain what he had done to his wise old mother? How could he unsay all that he had said to her a few days before when he had shown her that this trip to Brazil was quite for the best and bade her a fond farewell? Could he explain it to anyone, even to himself? Did he honestly believe all the plausible things he had said to Pougeot and the others about this crime? Was it really the wonderful affair he had made out? After all, what had he acted on? A girl's dream and an odd coincidence. Was that enough? Was that enough to make a man alter his whole life and face extraordinary danger? Was it enough?
Extraordinary danger! Why did this sense of imminent peril haunt him and fascinate him? What was there in this crime that made it different from many other crimes on which he had been engaged? Those holes through the wall? Well, yes, he had never seen anything quite like that. And the billiard player's motive in boring the holes and the woman's rôle and the intricacy and ingenuity of the murderer's plan—all these offered an extraordinary problem. And it certainly was strange that this candle-selling girl with the dreams and the purplish eyes had appeared again as the suspected American's sweetheart! He had heard this from Papa Tignol, and how Alice had stood ready to brave everything for her lover when Gibelin marched him off to prison. Poor Gibelin!
So Coquenil's thoughts ran along as he neared the Place de l'Etoile. Well, it was too late to draw back. He had made his decision and he must abide by it, his commission was signed, his duty lay before him. By nine o'clock he must be at the Palais de Justice to report to Hauteville. No use going home. Better have a rubdown and a cold plunge at the haman, then a turn on the mat with the professional wrestler, and then a few hours sleep. That would put him in shape for the day's work with its main business of running down this woman in the case, this lady of the cloak and leather bag, whose name and address he fortunately had. Ah, he looked forward to his interview with her! And he must prepare for it!
Coquenil was just glancing about for a cab to the Turkish bath place, in fact he was signaling one that he saw jogging up the Avenue de la Grande Armée, when he became aware that a gentleman was approaching him with the intention of speaking. Turning quickly, he saw in the uncertain light a man of medium height with a dark beard tinged with gray, wearing a loose black cape overcoat and a silk hat. The stranger saluted politely and said with a slight foreign accent: "How are you, M. Louis? I have been expecting you."
The words were simple enough, yet they contained a double surprise for Coquenil. He was at a loss to understand how he could have been expected here where he had come by the merest accident, and, certainly, this was the first time in twenty years that anyone, except his mother, had addressed him as Louis. He had been christened Louis Paul, but long ago he had dropped the former name, and his most intimate friends knew him only as Paul Coquenil.
"How do you know that my name is Louis?" answered the detective with a sharp glance.
"I know a great deal about you," answered the other, and then with significant emphasis: "I know that you are interested in dreams. May I walk along with you?"
"You may," said Coquenil, and at once his keen mind was absorbed in this new problem. Instinctively he felt that something momentous was preparing.
"Rather clever, your getting on that cab to-night," remarked the other.
"Ah, you know about that?"
"Yes, and about the Rio Janeiro offer. We want you to reconsider your decision." His voice was harsh and he spoke in a quick, brusque way, as one accustomed to the exercise of large authority.
"Who, pray, are