Frank longed to reach that b.u.t.ton. He longed to light the gas in order to look around for the intruder.

Of course he could have lighted it with a match; but he realized that such a thing might be just what the unknown hoped for and expected. The man might be waiting for him to strike a match.

The minutes fled.

"Something must be done," Merry at last decided.

Then he resolved to leave the door, move slowly along the wall, reach the b.u.t.ton and light the gas--if possible.

With the silence of a creeping cat, he inched along. Every sense was on the alert.

It took him a long time to come to the foot of the bed at the opening of the alcove, but he reached it at last. Was the masked man waiting for him in the darkness of the alcove? It seemed certain that he could be nowhere else in the room.

Frank hesitated, nerving himself for what might come. Surely it required courage to enter that alcove.

He listened, wondering if he could hear the breathing of the man crouching in the alcove.

He heard nothing.

Then every nerve and muscle seemed to grow taut in Merriwell's body, and, with one panther-like spring, he landed on the bed. In the twinkling of an eye he was at the head of the bed, and his fingers found the push b.u.t.ton.

Snap!--the gas came on, with a flare.

It showed him standing straight up on the bed, his hands clinched, ready for anything that might follow.

Nothing followed.

Frank began to feel puzzled.

"Why in the name of everything peculiar doesn't he get into gear and do something--if he's going to do anything at all?" thought the youth on the bed.

Again a bound carried him over the footboard and out into the middle of the room, where he whirled to face the alcove, his eyes flashing round the place.

The bed covering which had been flung over his head lay in the middle of the floor, where he had cast it aside.

Nothing stirred in the room. On a chair near at hand Frank could hear his watch ticking in his pocket.

Then the intruder had not taken the watch, which was valuable.

Frank glanced toward his clothes. He had carefully placed them in a certain position when he undressed, and there they lay, as if they had not been touched or disturbed in the least.

"Queer burglar," meditated Merry. "Should have thought he'd gone through my clothes first thing."

But where was the fellow? There seemed but one place for him, and Frank stopped to look beneath the bed.

There was no one under the bed. The wardrobe door stood slightly ajar.

"Ah!" thought Frank. "At last! He must be in there, for there is no other place in this room where he could hide."

Without hesitation, Frank flung open the door of the wardrobe, saying:

"Come out, sir!"

But the wardrobe was empty, save of such clothing and things as Frank had placed there with his own hands.

Merriwell fell back, beginning to feel very queer. He looked all around the room, walking over to a sofa across a corner and looking behind that. In the middle of the floor he stopped.

"This beats anything I ever came against!" he exclaimed. "Was it a spook?"

Then the pain in his throat, where those iron hands had threatened to crush his windpipe, told him that it was no "spook."

"And it could not have been a dream," he decided. "I know there was a living man in this room. How did he escape? That is one question. When it is answered, I shall know how he obtained admittance. And why did he come here?"

Frank examined his clothes to make sure that nothing had been taken. He soon discovered that his watch, money and such valuables as he carried about with him every day, were there, not a thing having been disturbed.

That settled one point in Frank's mind. The man had not entered that room for the purpose of robbery.

If not for robbery, what then?

It must have been for the purpose of wreaking some injury on Merriwell as he slept.

"I was warned by my feelings," Frank decided. "I was in deadly peril; there is no doubt of that."

Frank went to the window and looked out. It seemed a foolish thing to do, for he had looked out and seen that there was not even a fire escape to aid a person in gaining admittance to his room. The fire escape, he had been told, was at the end of the corridor.

It was a night without a moon, but the electric lights shone in the street below. Something caused Merry to turn his head and look to his left.

What was that?

Close against the face of the outer wall something dangled.

A sudden eagerness seized him. He leaned far out of the window, doing so at no small risk, and reached along the wall toward the object. With the tip of his fingers he grasped it and drew it toward him.

It was a rope!

"The mystery is solved!" muttered Frank, with satisfaction. "This explains how the fellow entered my room."

He shook the rope and looked upward. He could see that it ran over the sill of a window two stories above.

"Did he come down from there? Should have thought he would have selected a window directly over this. And did he climb back up this swaying, loosely dangling rope?"

Frank wondered not a little. And then, as he was leaning out of his window, the light of the street lamps showed him that a window beyond the dangling rope, on a level with his, was standing open.

The sight gave Merry a new idea.

"I believe I understand how the trick was worked," he muttered.

"That must explain how the fellow was able to vanish so swiftly while my head was covered by the bedclothes. With the aid of this rope, he swung out from his window and into mine. He could do it easily and noiselessly. While my head was covered, he plunged out of the window, caught the rope, and swung back. That's it!"