“Why, you’re crazy!  My uncle hardly knows Cuffer—­and I never heard of a man named Shelley.”

“I am not crazy, and you know I am speaking the truth,” answered Tom, calmly.  “Now you tell me where your uncle is or I’ll have you arrested.”

“You’ll not arrest me!” exclaimed Tad Sobber, and with a sudden movement he twisted himself free from Tom’s grasp.  “You follow me and you’ll get the worst of it!” he added, and darted across the park at top speed.

Tom made after the bully, but as luck would have it a nurse girl with a baby carriage got between them and before Tom could clear himself of the carriage Sobber was a good distance away.  He turned to the eastward, down a side street where a large building was in the course of erection.  He looked back and then skipped into the unfinished building.

“He shan’t catch me,” he muttered to himself, and ran to the rear of the building, amid piles of bricks and concrete blocks.  A number of workmen were present, but nobody noticed him.

Reaching the building Tom peered inside, but saw nothing of the bully.  He was about to go in when a warning cry reached him from overhead.

“Get back there, unless you want to be hurt!”

Tom looked up and saw a workman in the act of throwing down a mass of rubbish, broken bricks, sticks and old mortar.  He leaped back and the stuff descended in front of him and raised a cloud of dust.

“What do you want here, young man?” demanded the superintendent of the building as he came forward.

“I am after a boy who just ran in here.”

“Nobody here that I saw.”

“He just came in.”

“We don’t allow skylarking around here.  You make yourself scarce,” and the superintendent waved Tom away.

“I want to have that fellow arrested—­that is why he ran away from me.”

“Oh, that’s a different thing.  Go find him, if you can.”

The superintendent stepped aside and Tom entered the building.  But the delay had cost him dear, for in the meanwhile Tad Sobber had made good his escape by running back to the next street.  Tom looked around for over quarter of an hour and then gave up the chase.

“It’s too bad, but it can’t be helped,” he mused.  “I may as well go back to the park and wait for Dick and Sam.  I hope they caught that Cuffer.”

While Tom was talking to Sobber the other Rover boys had followed Cuffer to the elevated railroad station.  A train was just coming in and Cuffer bounded up the steps two at a time, with the boys not far behind.

“Stop that man!” cried Dick, to the crowd coming from the train.  But before anybody would or could act, Cuffer had slipped past the man at the ticket box and was trying to board one of the cars.  Dick essayed to follow, but the ticket box guard stopped him.

“Not to fast, young fellow.  Where’s your ticket?”

“I must catch that man—­he is wanted by the police,” answered Dick.