"Seems to have gone out," commented Jack in a whisper.

"Yes. They must have heard us and switched it off."

"Probably they've skipped out, too, worse luck!" came from Paul.

Indeed, as they listened, they could hear no sound from the bungalow, at the door of which they now stood. All was silent and dark within.

"Got a match?" Walter asked.

"Take my flashlight," returned Jack. "It's stronger than Cora's."

The brilliant white beam of light from the electric flash which Jack handed to Walter illuminated the interior of the living room. And at the sight which met the gaze of the boys, they could not restrain murmurs of astonishment.

"Well, would you look at that!"

"Same thing over again!"

"And right under our noses too! They never made a sound!"

"What is it?" called Cora, from where she and her chums stood waiting.

"Did you catch them?"

"Haven't yet," answered Walter, playing the light about the room. "But the furniture is all upset, just as it was the other day, only more so.

Come on up, girls. I guess there's no danger. The boys have probably skipped out, though we may get them yet. Jack, you go around to the side door. Paul, you cover the back. I'll take a run through the bungalow and stir them up."

Pausing to light a lamp in the living room, Walter ran up the stairs to the apartments of the girls, while Jack and Paul formed a guard outside the bungalow. The girls still remained a little distance away, awaiting developments.

But there were none-at least inside the bungalow. Walter came down stairs to report that no one was up there.

"But are things upset in our rooms?" asked Bess.

"And is anything taken?" Hazel questioned.

"I didn't stop to look," confessed Walter. "I was just trying to drive out intruders."

"None came out the door I was watching," declared Jack.

"Nor where I was," said Paul.

"How in the world did they get away so quickly?" asked Walter.

No one could answer him and they all turned their attention to the living room.

As Walter had said, it was more upset than on the other occasion. Every chair in the big apartment had been overturned, and in some cases two were jammed together, the legs interwoven. On a table two chairs had been piled, while the couch was turned completely upside down, and a stool perched on top of it, a sofa cushion surmounting that.

Other sofa cushions were tossed about the room, as though the intruders had been having a pillow fight, and in fact the whole room had that appearance.

"But nothing seems to have been taken," said Cora, after a look around, when the furniture had been put to rights.

"Better not be too sure," cautioned Walter. "Wait until you take a look upstairs. I only glanced around."

"How in the world could they do all this without making a noise?" asked Paul. "It seems to have been done in a hurry, and boys are rather clumsy-I know I was. They ought, by rights, to have stumbled all over themselves, doing this by the light of only a pocket flash. And yet we heard no racket as we ran up. It was all quiet."

"That's one queer part of it," admitted Walter. "It almost makes one believe in--"

"Ghosts! Go on and say it," challenged Cora. "You can't scare us."

"Any more than we are frightened now," said Belle.

"Are you frightened?" asked Jack.

"A little," she confessed. "Wouldn't you be-if you were I?"

"I might be," he admitted. "But we'll get at the bottom of this for you, and catch those youngsters."

"If we only could be sure they were boys," Belle murmured.

"Who else could it be?" asked Jack.

"Ask us something easier," suggested Paul. "Go ahead upstairs, girls, and see if anything is missing."

This advice was acted upon, and when the place was aglow with lights Cora and her chums took "an account of stock," as Jack said.

"Well, any of your 'war paint' missing?" he demanded of his sister when she came down.

"Only a few little trinkets," she said, "ribbons and things like that.

If it were not impossible, I should say girls had a hand in this."

"It isn't impossible," declared Walter. "Girls can do almost anything nowadays. But it isn't likely. Some boys are just as fond of bright things as are girls, and probably these youngsters hope to make neckties of your ribbons."

"Well, what are we going to do about it?" asked Jack, when they had sat discussing the curious happening for some time.

"What _can_ we do?" Walter demanded.

"I know one thing _I_ am going to do," declared, Belle, "and that is I'm going home in the morning."

"No!" cried Cora.

"I am if this mystery isn't cleared up. It's getting on my nerves horribly," and she gave a quick glance over her shoulder as a slight noise sounded.

"I did that," confessed Hazel, who had dropped a book.

"Don't do it again, my dear," begged Belle.

"Now look here!" cried Cora, "this won't do. We're going to stick it out. We agreed on that, you know. We're going to find out what this mystery is."

"That's what I say!" came from Bess.