When the children plan to send a letter to the person who leaves the gifts, they are prevented from doing so. Explain.
Jem is still not certain that it is Boo who is leaving the gifts in the secret knothole of the Radley oak tree, but the children are nevertheless dying to see what Boo looks like. So, Jem decides to send Boo a note asking him to come out and meet them. The children still fear the Radleys, however, and getting too close to the Radley house is not an option. Jem comes up with the novel idea of attaching a note to a fishing pole which he plans to slip inside a loose shutter of the house. While Jem is trying to deliver the note via the fishing pole, Dill is supposed to keep watch for any adults who might appear; he will ring a dinner bell as a warning. When the warning bell is sounded, Scout "reels around to face Boo Radley and his bloody fangs." But it is Atticus instead. Atticus tersely puts an end to the bell ringing, reads the note written on a "filthy piece of paper," and then lectures the children about bothering Boo.
"Son," he said to Jem, "I'm going to tell you something and tell you one time: stop tormenting that man." (Chapter 5)