"That's it," he said. "The murderer was here with her. When we came, he struck her a blow with his fist and gagged her so that we should not hear her moans."
"But how did he get away?"
"Through here . . . look . . . there is a passage connecting all the attics on the first floor."
"And from there?"
"From there, he went down the stairs of one of the other dwellings."
"But he would have been seen!"
"Pooh, who knows? The creature's invisible. Never mind! Send your men to look. Tell them to search all the attics and all the ground-floor lodgings."
He hesitated. Should he also go in pursuit of the murderer?
But a sound brought him back to the girl's side. She had got up from the floor and a dozen pieces of gold money had dropped from her hands. He examined them. They were all French.
"Ah," he said, "I was right! Only, why so much gold? In reward for what?"