When the governess recounts first arriving at Bly, she uses visual and auditory imagery to describe the surroundings:
I remember the lawn and the bright flowers and the crunch of my wheels on the gravel and the clustered tree-tops over which the rooks circled and cawed in the golden sky.
The "bright[ness]" of this scene suggests to the governess that this is a beautiful, happy place. Even the way she describes the sound of the wheels "crunch[ing]" on the gravel has a sense of pleasure in it, as if she's relishing the experience of arriving at a very fine place. But because readers know that the governess's story of her time at Bly ends in horror, there's a touch of dramatic irony to this moment—she thinks she's arriving at this wonderful, seemingly carefree place, but readers know this isn't the case. This creates a tension that draws readers through the novella, as they wait for the governess's idyllic view of Bly to crumble.
Sure enough, the narrative returns to this exact imagery when the governess first sees the ghost of Peter Quint on one of the towers:
I can hear again, as I write, the intense hush in which the sounds of evening dropped. The rooks stopped cawing in the golden sky, and the friendly hour lost, for the minute, all its voice. But there was no other change in nature, unless indeed it were a change that I saw with a stranger sharpness. The gold was still in the sky, the clearness in the air, and the man who looked at me over the battlements was a definite as a picture in a frame.
What's most interesting here is that, for a moment, it seems like the idyllic imagery really is ruined by the appearance of Quint—there's even a sudden hush in the "golden sky." But then the governess says that everything stays largely the same, insisting that "there was no other change in nature." This complicates the idea that Bly's beauty is ruined for her once she starts seeing the ghosts, as Henry James seems to understand that what's truly unsettling is the idea that horrifying things can happen in beautiful places.
In a conversation with Mrs. Grose about how to handle children, the governess metaphorically presents bad behavior as some sort of contaminant, as if it's infectious and has the power to corrupt others:
"You like them with the spirit to be naughty?" Then, keeping pace with her answer, "So do I!" I eagerly brought out. "But not to the degree to contaminate—"
"To contaminate?"—my big word left her at a loss. I explained it. "To corrupt."
She stared, taking my meaning in; but it produced in her an odd laugh. "Are you afraid he'll corrupt you?"
The metaphorical idea here is that bad behavior is contagious and has a very tangible impact on other people. This highlights the governess's fear that she might not be up to the task of caring for Miles and Flora. It also hints at her growing—but as of yet unarticulated—fear that there's something wrong with the children and that there's a reason nobody else has agreed to educate them since their last governess died.
By the end of the book, though, it's not all that clear whether the children "contaminate" the governess or if it's perhaps the other way around. Though the governess is terrorized by the idea that the children are in cahoots with the ghosts, it's possible that she has deluded herself and, in doing so, has ultimately "contaminated" the children with her fear. In this reading, the metaphorical idea of contamination is especially relevant, as Miles ends up dying under ambiguous circumstances—in keeping with the metaphor of contamination, it's arguable that he has been fatally infected by the governess's fear. If this is the case, then it's a good example of situational irony: the governess, who originally worried Miles might "contaminat[e]" her with his bad behavior, ends up "contaminat[ing]" him with her fears and anxieties.
When the governess recounts first arriving at Bly, she uses visual and auditory imagery to describe the surroundings:
I remember the lawn and the bright flowers and the crunch of my wheels on the gravel and the clustered tree-tops over which the rooks circled and cawed in the golden sky.
The "bright[ness]" of this scene suggests to the governess that this is a beautiful, happy place. Even the way she describes the sound of the wheels "crunch[ing]" on the gravel has a sense of pleasure in it, as if she's relishing the experience of arriving at a very fine place. But because readers know that the governess's story of her time at Bly ends in horror, there's a touch of dramatic irony to this moment—she thinks she's arriving at this wonderful, seemingly carefree place, but readers know this isn't the case. This creates a tension that draws readers through the novella, as they wait for the governess's idyllic view of Bly to crumble.
Sure enough, the narrative returns to this exact imagery when the governess first sees the ghost of Peter Quint on one of the towers:
I can hear again, as I write, the intense hush in which the sounds of evening dropped. The rooks stopped cawing in the golden sky, and the friendly hour lost, for the minute, all its voice. But there was no other change in nature, unless indeed it were a change that I saw with a stranger sharpness. The gold was still in the sky, the clearness in the air, and the man who looked at me over the battlements was a definite as a picture in a frame.
What's most interesting here is that, for a moment, it seems like the idyllic imagery really is ruined by the appearance of Quint—there's even a sudden hush in the "golden sky." But then the governess says that everything stays largely the same, insisting that "there was no other change in nature." This complicates the idea that Bly's beauty is ruined for her once she starts seeing the ghosts, as Henry James seems to understand that what's truly unsettling is the idea that horrifying things can happen in beautiful places.
There's some dramatic irony at play the first two times the governess sees the apparition of Peter Quint, since her entire narrative has already been framed as a ghost story. Therefore, readers already have an inkling that Quint must be a ghost, but the governess herself takes a little while to come to this conclusion.
The governess is deeply unsettled at first, and she seems to have an inclination from the very beginning that there's something suspicious and perhaps even supernatural afoot—and yet, she doesn't articulate this at first, not even to herself. Instead, she waits several days and goes through all of the possible explanations for why she might have seen an unknown man on one of the house's towers. She even wonders if perhaps the servants at Bly have pulled some sort of prank on her—she's somewhat relieved to decide, after a few days, that the servants haven't made her the "object of any 'game.'" But this conclusion (that nobody's playing a prank on her) leaves her grasping for answers:
There was but one sane inference: someone had taken a liberty rather gross. That was what, repeatedly, I dipped into my room and locked the door to say to myself. We had been, collectively, subject to an intrusion; some unscrupulous traveler, curious in old houses, had made his way in unobserved, enjoyed the prospect from the best point of view, and then stolen out as he came. [...] The good thing, after all, was that we should surely see no more of him.
In this passage, the governess decides that a stranger has trespassed by sneaking onto the grounds of Bly and mounting one of the towers. But thanks to the frame story and the heavy foreshadowing at the beginning of the novella, readers intuitively understand that the governess is wrong in this moment—the man she saw standing on the tower wasn't a wayward traveler. What's more, even though the governess confidently says she'll certainly "see no more of him" at Bly, it's quite obvious that she will see him again. After all, this is a ghost story, and it wouldn't be much of a story if this were the only time the ghost appeared. When the governess suggests these things to make herself feel better, then, readers understand that she's woefully mistaken, and this only adds to the mounting tension.