Summary of Section XVIII
The next day the governess tells Mrs. Grose she has written the letter to the uncle, but she keeps it in her pocket. The children are perfect at their lessons, and the governess is struck by Miles's intelligence and gentlemanly character. She can hardly keep from staring at him, wanting proof that he is indeed wicked. She believes he knows about evil, but she wants to know if he ever acted on it.
Miles takes the governess to the schoolroom where he plays on the piano for her. Meanwhile, Flora has run off, and everyone joins in looking for her. The governess declares she is with Miss Jessel. She finally puts her letter on the hall table to be taken to town to the mail as she and Mrs. Grose search for Flora.
Commentary on Section XVIII
The governess believes Miles has tricked her so Flora can run off by herself to be with Miss Jessel, and then, when they can't find Miles, she thinks he has gone off with Quint. This forces her to put the letter out to be mailed to the uncle.