"But however in the wide world do you think they got in here, if the old door is locked?" demanded Wagner, curiously, and wondering if Fred could give an answer to that question as easily as he seemed to solve other mysteries.

"I think a key has been used here lately," replied the other. "I can see marks around the keyhole to tell that. Chances are, they had one made to fit the door. A smart fellow could take an impression of the lock with wax, or something, and a locksmith would make him a key that would answer.

"But, perhaps, if two or three of us could get our shoulders against the old thing we might manage to force it. The chances are it's pretty punk, being so old; and the lock must be rusty, too."

"Then let's make a try; and me to be one of the pushers," Bristles said, as he began to get his sturdy frame locked in an attitude where he could exert the most force.

Fred and Wagner took their places alongside, managing to crowd in; while even Sid put his stick against the upper part of the door, as though meaning to add to the united pressure as well as he could.

"Ready?" asked Fred.

"Yep!" came from Bristles; while Felix grunted his assent.

"Then all together, now!" exclaimed the leader.

"She moved then, Fred!" gasped the pleased Bristles.

"Once more, fellows, and all together, give it to her!" Fred continued; and the three exerted themselves to their utmost to break the door's fastenings, or hinges, by a combination of their strength, which was considerable.