The professor squirmed out of the grasp of the two boys, and made a wild dash for the door.
Just before he reached it, the door was flung open, and Colonel Vallier, followed by Rolf Raymond, strode into the room.
The colonel and the professor met just within the doorway.
The collision was violent, and both men recoiled and sat down heavily upon the floor, while Rolf Raymond barely saved himself from falling astride the colonel's neck.
Sitting thus, the two men glared at each other, the colonel being in a dress suit, while the professor wore a night robe.
Frank and Barney could not restrain their laughter.
Then a most remarkable thing happened.
Professor Scotch became so angry at what he considered the unwarranted intrusion of the visitors that he forgot how he was dressed, forgot to be scared, and grew fierce as a raging lion. Without rising, he leaned forward, and shook his fist under Colonel Vallier's nose, literally roaring:
"What do you mean by entering this room without knocking, you miserable old blowhard? You ought to have your face thumped, and, by thunder! I believe I can do it!"
"Sah!" gasped the colonel, in the greatest amazement and dismay.