He jabbed the brad into something broad and round and fat.

Then there was a wild howl and an upheaval of that bed, as if an earthquake had occurred. Up came Bruce Browning, crimson in the face, and rubbing with both hands a portion of his person usually hidden by the tails of his coat.

“Confound you!” he roared. “I’m killed! You’ve stabbed me with that thing!”

Then, with remarkable agility, he pranced past the three professors and slammed the door, shouting:

“Up, fellows—up! This is a horse on us! It’s not the faculty! These fellows are in disguise, and they’re hoaxing us!”

Then the three professors made a break to get out by that door, dropping the match. The room was in darkness, and there was a furious battle for a few moments.

Some one brought out the lamp and lighted it. The light showed an interesting spectacle.

Browning, still up against the door, was seated on the fellow who had represented Prof. Such. Rattleton was holding down Prof. Babbitt; but it took Sidney Gooch and three others to keep the third one from getting away.

“It’s no use, fellows,” said Bruce, grimly. “We’ve got you, and you may as well give up.”

The false Prof. Mower did so, with a laugh.