"Did you ever meet McCarthy?" asked Darrow, as the elevator of the Atlas sprang upward.

"Never."

"Well, no matter what he says or does, I want you to say nothing--nothing."

"Correct," said Jack. "I'll down-charge."

"That's right," Darrow approved. "First of all, wait outside until I call you."

McCarthy was already at his desk, and in evil humor. When Darrow entered, he merely looked up and growled.

"Good morning," Darrow greeted him easily. "Any wireless this morning?"

McCarthy threw back his heavy head.

"That damn operator's been leaking!" he cried.

"So there are 'wireless'," observed Darrow. "No, your operator didn't leak. Who is he?"

"If he didn't leak, what did you say that for?"

"I'm a good guesser," replied Darrow enigmatically. "They say anything about a 'sign' being sent, and such talk?"

"You've been gettin' the dope yourself out of the air," returned McCarthy sullenly.

"Look here, my fat friend," drawled Darrow, his eyes half closing, "I'm getting nothing from anywhere except in my own gray matter. What do your messages have to say?"

"Why should I tell you?"

"Because I'm interested--and because I know who sent 'em."

"So do I," snarled McCarthy, in a gust of temper.

"And I'm beginning to suspect he's a man to look out for. And I doubt if you'll ever find him. Of course, he's responsible for the row last night--as well as for the trouble in the Atlas Building the night before."

"I don't know whether he is or not."

"Oh, yes, you do; and I do; and the wireless man does. We're the only three. The rest of them are still figuring on comets."

"Well?"

"I don't suppose there's any real doubt left in your mind but that this man can turn the juice off again, if he wants to?"

"I don't know as he did it," persisted McCarthy stoutly.

"Now, how long do you suppose you'd last if the public should get on to the fact that this hidden power was going to exert itself again unless you left town?"

A slight moisture bedewed McCarthy's forehead.

"Not all your police, nor all your power could save you, if the general public once became thoroughly convinced that it was to go through another experience like last night's unless it ousted you. Why, a mob of a million men would gather against you in an hour You see," drawled Percy Darrow, "why you'd better look after that wireless man of yours--and me."

"And you," repeated McCarthy. "What do you want?"

"I want to see those wireless messages, first of all," said Darrow, reaching out his hand.

McCarthy hesitated; then swiftly thrust forward the flimsies. Darrow, a slight smile curving his full red lips, held them to the light. They read as follows:

"McCarthy: A sign was promised you at six o'clock. It has been sent. Repent and beware! Go while there is yet time.

M."

There were four of these, couched in almost identical language. The fifth and last message was shorter:

"McCarthy: Flee from the wrath to come.

"M."

"What," said Darrow, "is to prevent the other operators who must have caught this message from giving it to the public? What, indeed, is to prevent M.'s appealing direct to the public?"

"I don't know," confessed McCarthy miserably. "Do you?"

"Not at this moment. Will you send for the operator who took these?"

McCarthy snatched down the telephone receiver, through which presently he spoke a message.

"What have you got to do with this?" he demanded, after he had hung up the hook.

"I want something," said Percy, "of course."

"Sure," growled McCarthy, once more back on familiar ground, and glad of it. "What is it?"

"I'll tell you when I'm sure whether I can do anything for you in this matter."

"If this fellow didn't leak, how did you know about them wireless?" demanded McCarthy again. "How do you know who's doin' this?"

Darrow smiled.

"The man who can control the juice as this man has is a scientific expert with a full scientific equipment. If he communicated at all, it would be by wireless, as that is the easiest way to cover his trail. I remembered your telephone message from the fanatic about sending a 'sign'. Immediately after, the Atlas Building experienced on a small scale what next day the city experienced on a larger scale. It was legitimate inference to connect one with the other. Of course, if our telephone friend was the man who had brought these things about, he had done it to force you to do what he demanded. But he would lose the effect of his lesson unless you understood his connection with the matter. Hence, I concluded that you must have received messages--by wireless--and that they must have repeated the warning as to a 'sign' being sent. It was very simple."

"You're smart, all right," conceded McCarthy.

After a moment the wireless operator came in.

"Simmons," said McCarthy, "answer this man's questions."

"They will be in regard to these messages," said Darrow. "Where are they from?"

"Somewhere in the one-hundred to two-hundred-mile circles, depending on the power of the sending instrument," replied the operator promptly.

"Are you sure?"

"I know my instruments pretty well; and I've had experience enough so I can tell by the sound of the sending about how far off they come from."

"And this was from somewhere about one to two hundred miles away, you think?"

"Yes, sir."

"Do you know whether any other instruments caught this?"

"No, only mine." He was very positive.

"How do you know?"

"Mr. McCarthy had me inquire."

"How do you account for it?"

"I don't know, except that maybe my instrument happened to be just tuned to catch it. That's another reason I know it was from far off. The farther away the sending instrument, the nearer exactly it has to be tuned to the receiving instrument. If it was nearer, 'most anybody'd get it."

Percy Darrow nodded.

"That's all, I guess. No, hold on. Did any of these come between six and eight last evening?"

For the first time the operator smiled.

"No, sir; my instrument was dead."

He went out.

"Well?" growled McCarthy.

"I don't know; but I can see more trouble."

"Let him turn off his juice," blustered the boss; "we'll be ready, next time."

Percy Darrow smiled.

"Will you?" he contented himself by saying. Then, after a moment's pause, he added, "I'll agree to stop this fellow if you'll give me an absolutely free hand. I'll even agree to find him."

"What do you want?"

"I want a job, a good engineering-construction job, for a friend of mine."

"What can he do?"

"He can learn. I want a good honest place where he can learn under a good man."

"Who is he?"

"I'll bring him in."

A moment later Jack, in answer to a summons, entered the office.

McCarthy stared at him. "What kind of a job?" he growled.

"Something active and out of doors," Darrow answered for him; "streets, water, engineering."

"It's a holdup," said McCarthy sullenly drawing a tablet toward himself, and thrusting the stub of a pencil into his mouth.

"A beneficent and just holdup," added Darrow; "the first of its kind in this city."

McCarthy glared at him malevolently.

"It don't go unless you deliver the goods," he threatened.

"Understood," agreed Darrow.

"What's his name?" demanded McCarthy, withdrawing the pencil stub, and preparing to write.

"His name," answered Darrow, "is John Warford, Junior."

McCarthy started to his feet with a bellow of rage, his face turning purple.

"Of all the infernal--!" he roared, and stopped, as though stricken dumb. For two or three words further his mouth and throat went through the motions of speech. Then an expression of mingled fear and astonishment overspread his countenance. He sank back into his chair. Percy Darrow nodded twice and smiled.