"He can't have got away!" Muggs exclaimed.

"Where did he go?" the chief demanded.

"He didn't come past us," one of the policemen declared. "I don't see how he got out of the circle. Why, he hasn't had time to get away; and the men in the street——"

The officers in the street already had been warned. The entire block was surrounded; it seemed impossible that the master criminal could escape.

"Maybe he dodged the boys here, but he'll never get away from the block!" the chief declared. "Have more searchlights turned on the lawn, and tell the men in the alley to keep awake. He can't be far!"

Out of the sky came a blinding light. It flooded the house and lawn, turned the night into day.

"That—that light——" Sheriff Kowen gasped.

The light disappeared. They waited, watching the sky. They were silent now. No sound reached their ears except the din from the house. They saw nothing.

And then they heard the Black Star's voice.

"Did you really think you had me?" it said. "I must admit that you have wrecked my plans and scattered my organization again. Some of my men will have to go to prison, I suppose, but you haven't caught me, never will catch me! I shall leave the city, and you cannot prevent it. I have prepared for this emergency. When my organization is formed again, perhaps I shall return. My campaign is over for the present, but there will be another!"

The voice died away. There was silence for a moment, and then the brilliant light flashed again, flooded the lawn, almost blinded the men there.

"There is a letter by the alley gate!" The voice of the Black Star now came to them faintly. "Good night, gentlemen!"

"Gone!" the chief gasped. "Gone!"

"But how on earth——" Kowen began.

"That letter!" Verbeck cried. "Let's get it!" They hurried to the alley gate, and there they found the letter, as the Black Star had said. They carried it back to the police automobile, and read it in front of the searchlight.

Gentlemen: If you have this letter, it means that my plans have been ruined, and that I have been forced to escape. I cannot neglect this chance to tell you how futile have been your efforts.

Have you wondered how I spoke to you out of the sky? Have you worried about the bright light? Are you surprised at the way I escaped you just now?

I have in my organization a wonderful man. He is a mechanical genius gone wrong. He has perfected airplanes as no man dreams they can be perfected. I have been using an airplane—but it is a noiseless airplane! Can you imagine what that would mean if the world had the secret? An airplane, as the public knows it, heralds its approach. With this, I can sail at night over the city, without making the slightest noise. I can hover over a certain spot——

Yes, I mean hover. For this airplane is so perfected that it can stand still in the air. It can be raised or lowered straight up or down. Do you understand now?

The airplane was hovering over the lawn, a rope ladder dropped from it. I merely climbed up the ladder as the airplane ascended. I am writing this in advance, but I know what I shall do, if forced. I always plan for every emergency, you see. And while you poor fools bite your nails in your chagrin, I shall be speeding through the air to a certain refuge I have prepared. There I shall recuperate and plan some more. *****

Roger Verbeck read the letter aloud. A chorus of gasps came from those who heard.

"Well, he is gone!" Verbeck said. "But his band is broken up, and that is something!"

"And if he ever comes back here, we'll get him, won't we, boss?" Muggs asked.

"We'll get him!" Roger Verbeck said. There was determination in his voice.

THE END