In the novel To Kill a Mockingbird, how does Scout stop the mob?

In Chapter 15, Atticus goes to the Maycomb jailhouse to sit outside of Tom Robinson's cell to make sure nobody tries to harm him. Jem is concerned for his father's safety and decides to check up on him. Scout and Dill tag along, and the three children hide next to Tyndal's Hardware Co. and watch as a group of men arrive in several cars. The men who get out of the cars and surround Atticus are known as the Old Sarum bunch. They intend to harm Tom Robinson and tell Atticus to get out of their way, but Atticus refuses to leave. While the men are telling Atticus how they've distracted Sheriff Tate, Scout runs out into the middle of the group because she is curious and anxious to hear the conversation. Scout enters the crowd of men, and Jem and Dill leave their hiding place to join her. Scout is unaware of the serious situation she has entered and spots a familiar face, Walter Cunningham Sr. She naively attempts to have a conversation with him by mentioning his entailment and his son, Walter. Walter Cunningham Sr. attempts to ignore Scout, but eventually acknowledges her. Walter squats down and says,"I'll tell him you said hey, little lady" (Lee 206). He then motions to the rest of the Sarum bunch and tells them it's time to leave. Scout's presence made Walter realize the precarious situation Atticus was in, and Walter recognized that he was in the wrong. Atticus explains to his children the next day that Walter is essentially a good man who simply fell victim to mob mentality.