on Van's right warned. "I heard somethin' about that, too, but you know what the penalty is for not keepin' your mouth shut!"
Van could tell by the movement of the man's body that the guard had gestured significantly at him.
In the prolonged, moody silence that followed, the Phantom tried to fathom the motives and extent of the mysterious organization that three times now had reared its ugly, poisonous head, There was but the one conclusion—some secret society was plotting to overthrow the government of the United States, and was relying upon some new unannounced discovery of modern science to effect their treacherous ends.
And that the dead Dr. Hugo Junes' metallurgical experiments with aluminum and calbite had something to do with those murderous plans appeared obvious. The Phantom was convinced that Dr. Junes' death had not been accidental, but a deliberate killing.
The doctor's pleading fear and final wild hysteria, the hypodermic syringe visible for an instant in one of the masked men's pockets, the whole set-up in the General Electric underground heat laboratory, in fact, pointed at murder. Junes must have been drugged and thrown against the top of that furnace.
But why should these hooded and masked members of such a secret organization kill Dr. Junes, a scientist whom they were using?
The obvious answer was that Junes had refused to conform to their demands. And now the Phantom himself was purposely letting himself be forced to take the murdered scientist's place in their subversive scheme. The disguise of Professor Paul Bendix had proved more real and convincing than Van had ever hoped.
His unanswered and unvoiced questions were interrupted by the slowing of the car. It stopped and, judging by the sounds, they had driven inside some building which, nevertheless, did not smell like a garage. The binding tape was ripped off his ankles and he was shoved out of the car.
His shoes crunched on cinders and there was a trace of coal gas in the air. Then he was being guided along an earthy-smelling, cool passageway that had the confining feel of a tunnel.
There were four men with him now, their rough voices sounding loud and echoing. They stopped him a hundred paces beyond. Van could feel unsteady board footing beneath him.
Something slammed suddenly, sounding like a gate. Mechanism grated and groaned into action. The Phantom, his pinioned arms still held by two of the men, experienced the sensation of being lowered slowly in an elevator.
The complaining, slow descent went on it seemed endlessly. Van had no way of reckoning how far down into the earth he was being carried, but the air became rapidly more gaseous and damp, the pressure heavier.
The guards with him had ceased talking, but their casual, almost illiterate conversation before had given him no inkling of where he might be, except for an occasional miner's phrase.
The elevator car stopped finally and Van was pushed into a narrow passageway. His shoulders rubbed against damp dirt walls, and he had to stoop to protect his head from the low, wooden beams bracing the roof.
From the voices only two men were with him now one in front and one behind. He was herded through an interminably long and crooked tunnel and several times he could feel with his shoulders different openings leading off. Whether or not they were following the main tunnel or any one of its branches, he had no way of knowing.
The floor was a steady decline, some parts steeper than others, but always descending. Five times, the Phantom counted, he was stopped while the exaggerated clicking and grating noise of a door being unlocked, opened, closed behind them and locked again, filled the accentuated silence about him.
The passage leveled out beyond the fifth door. He felt several more openings in the walls as he was shoved ahead. The tunnel twisted continuously, and the odor of gas increased, made breathing more labored.
Another door barred their passage, but there was no key in the possession of the guards for this one. One of them beat against the panel with what sounded like the butt of a gun—five swift blows, a pause and a single sixth.
On the other side a key turned with a click that echoed like an explosion in the compressed atmosphere. A bar scraped as it was slid away from the door on the opposite side. A moment later the door swung inward and the Phantom was pushed through, shoved up against a wall.
He heard the door being closed and locked. Then without preliminaries the tape was ripped off his wrists, torn off his eyes and mouth. Van opened his eyes slowly, slitting them against any unexpected light that might blind him after his long siege of complete darkness. But only a poor indirect glow lighted the cavernous room in which he found himself.
The two men who had brought him in stood on either side of him and one of them held a heavy long-barreled revolver. Both were dressed in overalls and miners' caps in which gleamed small electric bulbs.
Across the chamber stood a tall figure in a black-caped robe. The man had a black hood over his head and his face was covered with a mask through which his eyes glittered ominously. He might have been the same grim specter who had appeared at the General Electric sub-cellar laboratory. Even his voice when he spoke sounded similar in the deceiving echoes of the cavern.
"Professor Paul Bendix," he said contemptuously, "I hope the trip hasn't upset you."
Van eyed the hooded figure defiantly, wet his parched lips. "What manner of science is it," he demanded in the guttural voice of Professor Bendix, "that makes such humiliating experience necessary?"
The hooded man shrugged indifferently beneath his robe.
"Asking questions is not a part of your job here," the tall man stated flatly, and added significantly, "You witnessed what happened to your predecessor, Dr. Hugo Junes."
The Phantom stepped away from the wall, flexing his cramped muscles. In another corner of the cavern his eyes, accustomed to the peculiar light now, slid and settled on the bound and gagged figure of Jerry Lannigan. The big Irishman was watching him eagerly.
"You have my assistant here, I see!" the Phantom exclaimed, making his words ring with anger that covered the relief he felt. "Untie him!" This was no time for feeling his way. They evidently still thought he was an eminent scientist, and he had to continue his bluffing characterization.
"I had your assistant untied before," the cloaked leader in the room said. "He became unmanageable and fought, so I had him tied again to keep him from getting hurt. I hope that the fool will behave himself now that you are here."
"I'll guarantee that he will," Professor Bendix declared gravely. Yet within him was a warming glow at the thought of what damage the Champ had probably done before they overpowered him.
The hooded leader nodded to one of the guards, who went over and ripped the tape bonds from Lannigan's ankles, wrists and lips. The red-headed Irishman got to his feet, came over and stood belligerently beside the professor.
"This joint is ratty!" Lannigan growled at the man in the hood, and turned to Van. "The whole place is overrun with these guys dressed up like Ku Kluxers."
"Enough of that!" the leader snapped. "You'll find our organization very effective if you try any foolishness."
"Quiet," the Phantom warned Lannigan, and addressed the man in the black robe: "If I am to be put to work, I must see the laboratory. And I would appreciate knowing where I am."
The tall, hooded figure again jerked his head at the two mine guards and moved to another
