"I hope so," Duvall remarked, indifferently, then turned to the doctor. "Now, monsieur, let us have done with this farce as quickly as possible. I have no time to waste."
"Nor have I. Good-night, Miss Ellicott." He nodded pleasantly to Grace as she ascended the stairs, then addressed one of the two attendants. "Where is Herr Mayer?" he asked.
"He is waiting for you in the laboratory, Herr Doctor," the man replied.
"Good! This way, if you please." He motioned down the hall. "Be so good, Mr. Brooks, as to proceed at once."
Duvall started off down the hall in no pleasant frame of mind. The whole affair had been bungled by his stupidity. He passed through the door which Hartmann presently opened at the end of the hall, and found himself in a long narrow passage, lit by a single electric lamp. Hartmann closed the door carefully behind him, and came on down the corridor, his footsteps echoing loudly on the concrete floor.
At the end of the corridor a second door confronted them. It was opened by a tall blond man, with a reddish mustache and brilliant blue eyes. "I heard you coming," he said, nodding to Hartmann, then looked keenly at Duvall. "So this is the fellow, eh? Where shall we take him?"
The doctor pointed to an iron door which faced that by which they had entered. Between the two doors ran a narrow corridor, with an iron staircase to the left, leading upward. "In here," he said, shortly, and going to the door, opened it with a key which he drew from his pocket.
Again Duvall cursed his stupidity. For a moment, thoughts of resistance crossed his mind but he at once realized the hopelessness of it, and followed the doctor into the room. The tall man brought up the rear, closing the door silently after him.
The room was pitch dark. In a moment, however, Hartmann had pressed an electric button, and a brilliant light flooded the place. Duvall looked about him curiously, and in that fleeting glance saw that the room was without windows of any kind, and that the walls, smooth and white, contained no openings whatever, except the door by which they had entered. The floor, as he could tell by its feel under his feet, was of cement. The room was bare of furniture, but he perceived a number of boxes and packing cases standing about the walls.
The instant the door was closed, Hartmann sprang at the detective and grasped his two wrists. The latter had always been considered a powerful man, but the arms and shoulders of the doctor were those of a Hercules. "Search him, Mayer," he said, as he pinned Duvall's wrists together in his iron grip.