The policeman, whom we later learn is Jimmy Wells, asks Bob, the man in the doorway, a pointed question.
“I'll be on my way. Hope your friend comes around all right. Going to call time on him sharp?”
To which Bob replies:
“I should say not!” said the other. “I'll give him half an hour at least."
Jimmy has already decided not to let Bob go and not to arrest Bob himself. His question elicits the information he wants. Bob will be there for about thirty minutes. Jimmy must hurry to the precinct station and find another officer to make the arrest. As it turns out, Bob only waits about twenty minutes before the plainclothes detective arrives. Something the detective says to Bob suggests that the station is very close by.
"Come on, Bob; we'll go around to a place I know of, and have a good long talk about old times.”
The "place," of course is the station house, where Bob will be booked and locked up. The word "around" sounds as if the station house is just around the corner. If it was any great distance away from the hardware store, the plainclothes cop might have been forced to provide for transportation. But, on the other hand, if the station was very far away Jimmy might have been forced to make the collar himself.
Jimmy knows he has thirty minutes in which to act. Bob has told him he will wait there for a half-hour. Besides that, Bob has just lighted a cigar and will not want to leave the shelter of the doorway in this wet weather until he has finished his smoke. A cigar lasts a long time.
Jimmy would have to go to the station house because that is the only place where he could be sure of finding other cops. He is a beat cop in this precinct, so he would know everybody at the station. In the note that Jimmy leaves for Bob he uses the word "around" too, suggesting that the station house is practically around the corner.
Somehow I couldn't do it myself, so I went around and got a plainclothesman to do the job.