By opening a way in, the miscreant had, for Roger, made clear a way out. He was, then, in no vital trap.
He could afford to drive back panic, to think carefully what to do.
If the whole building had been short-circuited, the telescope was no longer charged. He had climbed it. Climb it he could again.
His problem, though, was to trap his unknown adversary if he could.
With no electrical help he must think out a plan.
It must be clever, Roger knew. His menace was from a man as brainy as was his cousin. And that, Roger felt, was a compliment to a very unjustified person.
He thought he knew what the crash had been. Something deliberately upset in the cellar, to scare him. It had come about as long after the flash as would have been consumed in rising to the roof on a rope, scuttling down the fire escape, opening the cellar coal chute, and climbing down.
He estimated the time that had since elapsed. The adversary had by now gotten up the cellar stairway and would be on the ground floor.
Would he come further or try to lure Roger down, the solitary youth wondered.
He must let that become apparent by what his keen ears would detect.