Dickens compares both Pip and Provis to dogs several times in Great Expectations. This simile is used to explain a difference in power between characters, and also to indicate animalistic or uncivilized actions in the "dog"-like figure. In. Chapter 3, when Pip brings Provis food and drink as he hides in the marshes, he compares the convict directly to an animal he knows:
I had often watched a large dog of ours eating his food; and I now noticed a decided similarity between the dog’s way of eating, and the man’s. The man took strong sharp sudden bites, just like the dog. He swallowed, or rather snapped up, every mouthful, too soon and too fast; and he looked sideways here and there while he ate, as if he thought there was danger in every direction [...] he was very like the dog.
Provis has reverted to an animal-like state after his escape from the prison-barge, as he snaps and bites at his provisions. Pip is frightened, but he also feels sympathy for Provis as he would for a hungry dog. The sense of desperation Provis feels is amplified by the frantic language Dickens uses here; Provis doesn't eat, he "swallows" his food "too soon and too fast."
When the simile of the dog occurs in Great Expectations it always indicates a difference in status. This is true between Pip and Provis above, but also between Pip and Estella when she treats him "like a dog in disgrace." She makes him follow her like a dog and treats him as subhuman until much later in the novel. When Provis first meets Pip he calls him a "young dog" and a "fierce young hound," foreshadowing their later connection. Finally, when Provis reveals that it is himself and not Miss Havisham who is Pip's patron, he refers again to this simile, calling himself an "old dunghill dog." The human-and-dog relationship in literature is a classic trope of superior and subordinate, and Dickens uses it as shorthand here to indicate unequal relationships and social standings.
In the early part of the novel when Pip is still a young boy, Dickens uses a fairytale-esque simile to describe Pip's surrounding environment. Looking out of his windows on the morning he must bring "wattles" to the escaped convict Provis in Chapter 3, a guilt-stricken Pip observes that
It was a rimy morning, and very damp. I had seen the damp lying on the outside of my little window, as if some goblin had been crying there all night, and using the window for a pocket-handkerchief.
The image of a goblin crying and wiping its nose on the window evokes similar sensations that thinking of a damp, boggy marshland might: wetness, sliminess, mucus. Dickens repeatedly uses the word "damp" in this passage, first as a description of the morning's weather, and then as a discrete object "lying on the outside" of his window. Even from the relative warmth and safety of his bedroom, the "damp" is a goblin, a thing on the windowsill, and a condition of the day itself. The sense of discomfort evoked here also applies to Pip's internal feelings, as he worries about stealing and about helping a known criminal.
As a boy, Pip is very superstitious and scared of the supernatural. The fact that he sees the damp window as being like a visitation by a goblin foreshadows his fear of both the marshes themselves and of Provis. He has been told he must bring food and a metal file to the convict on pain of death, which seems like a more realistic threat than a goblin. Even given this, he almost doesn't leave the house because the misty, soggy world outside seems too much to bear.
When he recounts how his family and their friends treated Pip at home, Dickens uses a simile to liken the little boy to a bull in a Spanish bull-ring. When the Gargerys have company over in chapter 4 and Pip is forced to sit at the table with them, they will not give him a moment's respite from criticism:
But they wouldn’t leave me alone. They seemed to think the opportunity lost, if they failed to point the conversation at me, every now and then, and stick the point into me. I might have been an unfortunate little bull in a Spanish arena, I got so smartingly touched up by these moral goads.
In the kind of Spanish bullfighting arena Dickens alludes to, a young bull is aggravated by fighters who tease it into a frenzy. It is then killed by being stabbed with a sword. While none of the "company" actually want to murder Pip, part of the attraction of coming to dinner is to see him humiliated and cowed. The conversation is so "pointed" here, so cruel and critical of the little boy, that it actually "sticks" into Pip, like the spears used to enrage, confuse, and disable the bull before the matador eventually kills it. The "smarts" (little stings) he feels are the moments of shame and confusion when everyone criticizes him in a "particularly unpleasant and personal manner," as he says after this.
Dickens describes Pip's early childhood as being a battle waged between the boy and his unwelcoming and limiting home environment. For example, a simile in Chapter 4 emphasizes how restrictive all aspects of his upbringing were. Pip tells the reader that
I was always treated as if I had insisted on being born, in opposition to the dictates of reason, religion, and morality, and against the dissuading arguments of my best friends. Even when I was taken to have a new suit of clothes, the tailor had orders to make them like a kind of Reformatory, and on no account to let me have the free use of my limbs.
A "reformatory" in the Victorian period was a kind of prison for youthful lawbreakers. They provided free labor for the owners while the institution both punished and attempted to remold them. Pip's clothes constrain him, giving him no "free use" of his limbs and enforcing modes of movement and behavior. Mrs Joe tries to restrain Pip in every way she can, including literally straitjacketing him with his new outfit, depriving him of "free use of his limbs." Saying he had seemingly "insisted" on being born is a funny phrase in this context, but it also underlines just how dissatisfied Mrs Joe Gargery is in her role as his guardian. She is exasperated just by the fact of his being, and believes it to be his fault, "in opposition to the dictates of reason, religion and morality." Pip knows her dislike of his "crime" of existence is unreasonable even as a child, but can see the full extent of its ridiculousness as an adult narrator looking back.
Although education in Victorian England was one of the political priorities of the monarchy and the government, learning to read was by no means a guaranteed skill for Victorian working-class children. Dickens likens Pip's efforts to succeed in getting an education against difficult odds to crawling through a blackberry bush in Chapter 7:
Much of my unassisted self, and more by the help of Biddy than of Mr. Wopsle’s great-aunt, I struggled through the alphabet as if it had been a bramble-bush; getting considerably worried and scratched by every letter. After that, I fell among those thieves, the nine figures, who seemed every evening to do something new to disguise themselves and baffle recognition. But, at last I began, in a purblind groping way, to read, write, and cipher, on the very smallest scale.
This passage is full of vivid descriptions of struggle, pain, and humiliation. As Pip's schoolteacher, the elderly great-aunt of Mr. Wopsle is so inadequate that he is forced to rely on the help of his friend Biddy and his "unassisted self" for his education. Blackberry (or "bramble") bushes are notoriously thorny and tangled, snagging and impeding any attempt to get through them. Dickens doesn't refer to blackberries themselves at all here, making the struggle to get through the "alphabet" by Pip seem even more difficult and (literally) fruitless. He pulls his way through in a "purblind" or half-blind way, "getting scratched by every letter" as this task is so challenging.
The "nine figures" Pip refers to here are the Roman numerals from 1-9, indicating his attempts to teach himself math in addition to literacy. This is also a biblical allusion by Dickens to the parable of the Good Samaritan, a man who was beaten almost to death by robbers. Like the bramble-bush, Pip finds numbers, or "those thieves," to be a formidable foe in his quest for self-improvement.
In Chapter 8 Pip is reprieved from Miss Havisham's "sick fancies" by being allowed to call Estella back to the wedding chamber where the crone lives. Dickens uses a simile comparing Estella to a star to designate Pip's feeling of salvation when she returns. Pip "roars out" her name, and
her light came along the long dark passage like a star.
When she returns to the room, Estella brings "light" to the darkness, living up to her name. Dickens is famously adept at naming characters in a unique and often charming way that reflects their personality—in this novel alone, the reader gets to enjoy "Bentley Drummle," "Herbert Pocket," and "Mr. Pumblechook"—but this one is simple. Estella means "star."
Dickens, like the modern reader, would have known that the stars were many trillions of miles away from London, and that the light from them was very old by the time it was visible to humans. Estella, whether she is in the room with Pip or coming "along the long dark passage" is like the light of a faraway star: she is beautiful and alluring, but also cold, distant, and somewhat dead. Pip longs to draw closer to her, but the only real impression he can get of her is a superficial one, like seeing the tiny white pinprick of a star which would actually be a molten sun if one could get close enough. Even so, and although she is awful to him, Estella's bright presence is far better for Pip than being alone with Havisham in the dark and gloomy museum of her failed wedding.
When describing the painful tragedy of Miss Havisham's living diorama of decay, Dickens uses simile to liken her withered body and clothes to the yellowed and wilting flowers around her. This gives a powerful sense of the dried-out, barren environment in her mansion in Chapter 5:
But, I saw that everything within my view which ought to be white, had been white long ago, and had lost its lustre, and was faded and yellow. I saw that the bride within the bridal dress had withered like the dress, and like the flowers, and had no brightness left but the brightness of her sunken eyes.
A sense of the enormous amount of time that has passed since her "wedding" is given here through the visual language of "yellowing"; like old paper, Havisham's white dress, white skin, and white-blond hair have faded to a sickly yellow. Brides in Victorian Britain, especially in the upper echelons of city life, were under a social obligation to remain virgins until marriage. The white wedding dress was then (and remains now) a symbol of this physical "purity," but in Satis House this idea becomes corrupted. The fabric and flowers of Havisham's wedding outfit, which "ought to be white," have been left untouched for too long, turning crisp and yellow. Dickens implies through this that they reflect the state of the abandoned body living within them. Havisham is her wedding dress, as she has reduced herself to a caricature of a jilted bride. Dickens likens the "bride" first to her "withered" dress and then to the "withered" flowers, setting up multiple layers of dry, dead, and infertile imagery around her still-living body.
In the play set in Denmark that Pip and his companions attend in Chapter 31, Dickens uses a humorous idiom that also functions as a simile, likening the character of the Queen of Denmark to the metal she wears:
The Queen of Denmark, a very buxom lady, though no doubt historically brazen, was considered by the public to have too much brass about her; her chin being attached to her diadem by a broad band of that metal (as if she had a gorgeous toothache), her waist being encircled by another, and each of her arms by another, so that she was openly mentioned as “the kettle-drum.”
Being considered "brassy" or "brazen" would have been a criticism for a Victorian woman, as both words mean "loud" and "obvious" in this context. Being polite, quiet, and retiring was considered to be proper behavior for ladies at this time, so the "brass" in this woman is not necessarily a kind judgement by Pip. Dickens links the real brass the actress is wearing here to the "historically brazen" character she plays. The passage uses a second simile to make her seem even more comical, as Pip tells the reader she was "openly mentioned as the kettle-drum" because of all the rings of brass on her body.
In Chapter 39, when Pip's true patronage is revealed, Dickens describes the unreadable feelings displayed on Provis's face through the use of a paradox. As the returned convict gazes at Pip, the narrator describes his expression as
A smile that was like a frown, and with a frown that was like a smile.
This description is almost an oxymoron, as the two similes would usually cancel each other out. A frown is usually considered to be the opposite of a smile. The fact that Pip cannot tell which expression the older man is making illustrates how discomfited he is by the interaction. The paradoxical nature of this expression also reflects Provis's dominance over the situation, as Pip cannot interpret his purpose. Provis has been waiting a long time to explain to Pip how he has been supporting him, and by making his face this unreadable, he prolongs the agony of suspense for Dickens's protagonist.
This exchange between Pip and an older man also echoes another more conventional oxymoron that refers to a facial expression—the one made by the pompous Mr. Pumblechook in Chapter 29. When Pumblechook gives Pip a "frowning smile," he is also showing his dominance of a situation by asking a series of leading questions to draw Pip to a desired conclusion.
When Mr and Mrs Wemmick—Mr Jagger's long-suffering legal clerk and his stiff but pleasant sweetheart Miss Skiffins—finally get married in chapter 54, Dickens uses a simile to describe the new bride in a way that relates her body to a stringed instrument. This description deftly indicates that though the young woman herself hasn't changed, her attitude has:
It was pleasant to observe that Mrs. Wemmick no longer unwound Wemmick’s arm when it adapted itself to her figure, but sat in a high-backed chair against the wall, like a violoncello in its case, and submitted to be embraced as that melodious instrument might have done.
Miss Skiffins did not like to be touched by Wemmick before this. In a characteristically wry moment when the as-yet-unmarried couple are together but chaperoned in Chapter 38, Dickens describes her as having the "neatness of a placid boxer" in removing Wemmick's hand from her waist. She is absolutely in control of the situation, like a boxer restraining his might in a moment of being "placid."
Now that she is married, however, the new Mrs Wemmick allows herself to be "embraced," like a "violoncello in its case." The "case" here is a reference to her wedding dress, with her "figure" encased in it. Conflicting imagery of tightness and tension repeats here, as Dickens describes Wemmick's arm as "winding" around the body of a delicate stringed instrument. Even as she submits to it, though, Mrs. Wemmick doesn't seem particularly thrilled about the change, as she is still stiff and unyielding like the hard body of a cello.