What are some examples of cowardice in the novel To Kill a Mockingbird?

Bob Ewell, the novel's antagonist, does several things that can be considered cowardly throughout the novel. Throughout the trial of Tom Robinson, Bob Ewell was exposed as an alcoholic liar who assaulted and molested his own daughter. Following the trial, Bob Ewell attempts to enact his revenge on those who "ruined" his reputation. In Chapter 27, Bob Ewell loses his job working for the WPA and openly accuses Atticus of getting him fired. Bob displays cowardice by not taking responsibly for being fired and blames Atticus, who had nothing to do with it. The next person Bob attempts to get back at is Judge Taylor. Bob attempts to sneak into his house but runs away like a coward when he hears Judge Taylor coming downstairs. Instead of approaching Judge Taylor face to face and expressing his grievances, Bob attempts to confront him when he least expects it, which is cowardly. Another example of cowardice throughout the novel is when Bob Ewell attempts to scare Helen Robinson by following her to work and threatening her. Threatening an innocent woman who has recently lost her husband is something only a coward would do. That example pales in comparison to Bob Ewell's most cowardly moment in the novel. In Chapter 28, Bob attempts to kill Jem and Scout when they are walking home alone after the Halloween festival at the school. Attacking defenseless children is by far the most cowardly thing an individual can do.