A minute or two passed. The clocks struck the half hour. Hanaud leaned his ear against the panels of the door. He could not hear one sound within the house. He rang again; and after a few seconds shutters were thrown back and a window opened on the floor above. From behind the window someone whispered:
“Who is there?”
“The police,” Hanaud answered, and at the window above there was silence.
“No one is going to do you any harm,” Hanaud continued, raising his voice impatiently. “We want some information from you. That’s all.”
“Very well.” The whisper came from the same spot. The man standing within the darkness of the room had not moved. “Wait! I will slip on some things and come down.”
The window and the shutter were closed again. Then through the chinks a few beams of light strayed out Hanaud uttered a little grunt of satisfaction.
“That animal is getting up at last. He must have some strange clients amongst the good people of Dijon if he is so careful to answer them in a whisper.”
He turned about and took a step or two along the pavement and another step or two back like a man upon a quarter deck. Jim Frobisher had never known him so restless and impatient during these two days.
“I can’t help it,” he said in a low voice to Jim. “I think that in five minutes we shall touch the truth of this affair. We shall know who brought the arrow to him from the Maison Grenelle.”
“If anyone brought the arrow to him at all,” Jim Frobisher added.
But Hanaud was not in the mood to consider ifs and possibilities.
“Oh, that!” he said with a shrug of the shoulders. Then he tapped his forehead. “I am like Waberski. I have it here that someone did bring the arrow to Jean Cladel.”
He started once more his quarterdeck pacing. Only it was now a trot rather than a walk. Jim was a little nettled by the indifference to his suggestion. He was still convinced that Hanaud had taken the wrong starting point in all his inquiry. He said tartly:
“Well, if someone did bring the arrow here, it will be the same person who replaced the treatise on Strophanthus on its book shelf.”
Hanaud came to a stop in front of Jim Frobisher. Then he burst into a low laugh.
“I will bet you all the money in the world that that is not true, and then Madame Harlowe’s pearl necklace on the top of it. For after all it was not I who brought the arrow to Jean Cladel, whereas it was undoubtedly I who put back the treatise on the shelf.”
Jim took a step back. He stared at Hanaud with his mouth open in a stupefaction.
“You?” he exclaimed.
“I,” replied Hanaud, standing up on the tips of his toes. “Alone I did it.”
Then his manner of burlesque dropped from him. He looked up at the shuttered windows with a sudden anxiety.
“That animal is taking longer than he need,” he muttered. “After all, it is not to a court ball of the Duke of Burgundy that we are inviting him.”
He rang the bell again with a greater urgency. It returned its shrill reply as though it mocked him.
“I do not like this,” said Hanaud.
He seized the door-handle and leaned his shoulder against the panel and drove his weight against it. But the door was strong and did not give. Hanaud put his fingers to his mouth and whistled softly. From the direction whence they had come they heard the sound of a man running swiftly. They saw him pass within the light of the one street lamp at the corner and out of it again; and then he stood at their side. Jim recognised Nicolas Moreau, the little agent who had been sent this very morning by Hanaud to make sure that Jean Cladel existed.
“Nicolas, I want you to wait here,” said Hanaud. “If the door is opened, whistle for us and keep it open.”
“Very well, sir.”
Hanaud said in a low and troubled voice to Frobisher: “There is something here which alarms me.” He dived into a narrow alley at the side of the shop.
“It was in this alley no doubt that Waberski meant us to believe that he hid on the morning of the 7th of May,” Jim whispered as he hurried to keep with his companion.
“No doubt.”
The alley led into a lane which ran parallel with the street of Gambetta. Hanaud wheeled into it. A wall five feet high, broken at intervals by rickety wooden doors, enclosed the yards at the backs of the houses. Before the first of these breaks in the wall Hanaud stopped. He raised himself upon the tips of his toes and peered over the wall, first downwards into the yard, and then upwards towards the back of the house. There was no lamp in the lane, no light showing from any of the windows. Though the night was clear of mist it was as dark as a cavern in this narrow lane behind the houses. Jim Frobisher, though his eyes were accustomed to the gloom, knew that he could not have seen a man, even if he had moved, ten yards away. Yet Hanaud still stood peering at the back of the house with the tips of his fingers on the top of the wall. Finally he touched Jim on the sleeve.
“I believe the back window on the first floor is open,” he whispered, and his voice was more troubled than ever. “We will go in and see.”
He touched the wooden door and it swung inwards with a whine of its hinges.
“Open,” said Hanaud. “Make no noise.”
Silently they crossed the yard. The ground floor of the house was low. Jim looking upwards could see now that the window above their heads yawned wide open.
“You are right,” he breathed in Hanaud’s ear, and with a touch Hanaud asked for silence.
The room beyond the window was black as pitch. The two men stood below and
