Quickly he slipped from the room, and stepped outside the front door just as a door on the upper floor slammed to.
Chester walked slowly down the street, whistling.
"I hope he comes this way," he told himself. "Otherwise, I shall have to do some fast walking."
Fortune favored the boy. As he walked slowly along, a man brushed swiftly past him. Taking care to avoid all pretense of pursuit, Chester followed.
CHAPTER XXII.
CHESTER DISCOVERS A PLOT.
For half an hour the lad stalked his prey through the streets of the city, winding about here and there until Chester had absolutely lost his sense of direction. Several times the man turned round and glanced furtively about, but apparently he took no notice of his shadow.
Finally he turned into a crooked little street near the outskirts of the city. Chester also turned the corner, just in time to see the man descend a pair of steps into the basement of what was apparently an unoccupied house.
The lad hurried up and arrived in time to hear the man give a peculiar knock at the door—one loud tap, followed by three soft taps, then another loud one.
Chester walked back around the corner, where he stopped to think.