Alone after defending Mr. Thornton from the rioters at Marlborough Mills, and knowing people are accusing her of doing this out of romantic motives, Margaret speaks her distress aloud in a soliloquy:
"It was not fair," said she, vehemently, "that he should stand there—sheltered, awaiting the soldiers, who might catch those poor maddened creatures as in a trap—without an effort on his part, to bring them to reason. And it was worse than unfair for them to set on him as they threatened. I would do it again, let who will say what they like of me. If I saved one blow, one cruel, angry action that might otherwise have been committed, I did a woman’s work. Let them insult my maiden pride as they will—I walk pure before God!"
Note that though soliloquies most often occur in plays, Gaskell uses the device in the novel in the exact same way—letting a character speak in private such that only the reader can "hear" their thoughts. Here, Margaret bursts out in frustration at both Thornton (who threatened to let soldiers come in to break up the riot, instead of reasoning with the workers) and at the workers (who threatened Thornton with violence). Yet even though Margaret's actions have put her in an awkward position and possibly damaged her reputation, she doesn't regret them—she believes she has acted properly and with integrity before God.
The soliloquy allows readers to hear Margaret's motivations and reactions to this climactic event in a way they couldn't otherwise. After all, she couldn't express them to Thornton in the heat of the moment, or while she was knocked unconscious by the thrown pebble; and she doesn't want her parents to know about the incident, so a private outburst is the only option available to her. Though Gaskell could have described Margaret's thoughts solely through third-person narration, her use of soliloquy allows Margaret's passion to get through with greater immediacy, helping readers grasp the stakes of what's happened.
The morning after Margaret's melancholy visit to her home village, the novel uses a soliloquy to show how Margaret's perspective has shifted regarding all the changes in Helstone.
‘After all it is right,’ said she, hearing the voices of children at play while she was dressing. ‘If the world stood still, it would retrograde and become corrupt, if that is not Irish. Looking out of myself, and my own painful sense of change, the progress all around me is right and necessary. I must not think so much of how circumstances affect me myself, but how they affect others, if I wish to have a right judgment, or a hopeful trustful heart.’
Though soliloquies typically appear in drama, in North and South Gaskell uses private speech in the same way—to give readers direct insight into characters' inner thoughts. Here, as Margaret reflects on her day, the sound of playing children connotes hope for the future, a sign that life in Helstone will go on, even if Margaret isn't there to see it.
Throughout her visit, Margaret has been lamenting Helstone's changes, but she now reflects that change is necessary and that progress can benefit others, even if change sometimes feels painful for her personally. After all, if life stood still, it would stagnate and even regress. (Her aside "if that is not Irish" is a 19th-century expression that basically means, "if that doesn't contradict itself.")
Gaskell uses soliloquy to place heavier emphasis on key moments in Margaret's development, and so she does here: Margaret takes a decisive step toward being able to bid Helstone a peaceful farewell instead of just a grieving one. Margaret's desire to uphold "right judgment" and a "hopeful trustful heart" also points to her strong moral compass. Ultimately, she wants to be someone who cares about others' well-being. This moment shows that Margaret is maturing beyond self-serving nostalgia and focusing on the needs of the broader world.
