For over an hour the professor kept up such an interesting discourse that Frank was charmed. The train was slowing up, and the professor, leaning close to Frank, was pouring into his ear a description of a leaping kangaroo film among his treasures, when Frank straightened up suddenly and fixed his eye upon a man who had just left his seat and was coming down the aisle.
In a flash Frank recognized him as the person he had seen at the city railway station with the hollow satchel. The fellow carried the article now. He swung along as if it was heavy, which Frank knew could not be the case. He stumbled as he passed the seat containing the professor and Frank and seemed to momentarily drop his satchel to the floor as if to regain his balance.
Frank’s nerves thrilled as the man picked up his satchel again. A jerk moved the strap upon which Frank had his foot. He arose quickly and turned his head. The professor’s satchel was gone!
The man, who Frank knew in a flash must have taken it up inside his “patent” satchel, was hurrying to the door of the car. With a bound our young hero, guessing at the shrewd trick attempted, was after him.
“Hold on, there!” shouted Frank, so sharply that he attracted the attention of everyone in the coach.
“Meaning me?” retorted the fellow he was after, as Frank ran up to him and grabbed one arm.
“Yes, I do,” cried Frank. “You just took a satchel from behind that seat yonder and I want it.”
“Nonsense! What are you talking about?” shouted the man. “Don’t delay me. This is my station. Let go!” But Frank had slipped his hand down to the satchel the man swung about, and deftly reversing it, unset the stolen satchel from the coiling springs that had caught it up and held it.
“You meddler!” he hissed savagely. The man saw that he was unmasked and outwitted, and with a vicious swing brought his own satchel against Frank’s head. The latter went spinning to the floor, but he held on to the professor’s property.
“Astonishing!” exclaimed his fellow-traveler, arising in wonder to his feet. “Stop that man!” But the fellow whom Frank had baffled darted for the rear door of the car, leaped outside, slammed it shut after him and sprang to the platform of the station before the train stopped.