In Chapter 1, the novel uses a metaphor to compare Billy Bones's appearance to Doctor Livesey's:
I followed him in, and I remember observing the contrast the neat, bright doctor, with his powder as white as snow, and his bright, black eyes and pleasant manners, made with the coltish country folk, and above all, with that filthy, heavy, bleared scarecrow of a pirate of ours sitting far gone in rum, with his arms on the table.
The passage draws the reader's attention to the physical differences between the Doctor and Billy. The Doctor looks bright, clean and healthy, while Billy Bones's appearance is likened to a tattered, dingy scarecrow. Through this figure of speech, Stevenson paints a clear image that allows the reader to picture Billy Bones more vividly as they read. The comparison to a scarecrow also draws a sharp contrast between Billy and the Doctor. Much like a scarecrow, Billy is a menacing and frightening presence.
The opposing images of lightness and darkness also reflect Billy and the Doctor's personalities. White as a color typically symbolizes innocence, peace, and goodness, while the color black generally symbolizes death, evil, and misfortune. The novel presents the Doctor as responsible and respectable, a man Jim can rely on and trust. Billy Bones, on the other hand, cuts a frightening figure with his raving drunkenness, and his presence at the Admiral Benbow only leads to chaos.
Moreover, the color black is an important recurring motif in Treasure Island. Jim sees Billy murder another pirate named Black Dog. The color shows up again when Billy receives the Black Spot from Pew, a pirate summons that foreshadows death.
In Chapter 5, Jim secretly watches as the blind pirate Pew and a fellow buccaneer fight over Billy Bones's sea chest and the missing treasure map. Frustrated because the map has been stolen, Pew uses a metaphor and declares to the man:
If you had the pluck of a weevil in a biscuit you would catch them still.
Pew's unusual phrase isn't meant to be taken literally. It is a figure of speech in which he subtly compares the man to a "weevil in a biscuit." "Weevil" refers to a type of invasive beetle known to be a pest. To "have pluck" means to be brave and tenacious. Pew insults the man by making this comparison, telling him he doesn't even have the courage of a bug. In doing so, he provokes the man to be more courageous and ruthless in their pursuit of the treasure.
The novel uses this metaphor to present the idea of courage to the reader in a unique and memorable way. The pirate Long John Silver becomes a model of this exact type of courage. Extremely clever and bold, his bravery repeatedly allows Silver to escape death and punishment. Once Jim finds himself on the strange, perilous adventure to Treasure Island, he learns that courage is an especially important trait to have and something he must cultivate within himself in order to face difficult challenges.
Chapter 13 opens with the crew's first morning on the island. Jim describes the surrounding landscape using visual imagery:
Grey-coloured woods covered a large part of the surface. This even tint was indeed broken up by streaks of yellow sandbreak in the lower lands, and by many tall trees of the pine family, out-topping the others—some singly, some in clumps; but the general coloring was uniform and sad. The hills ran up clear above the vegetation in spires of naked rock.
In this passage, the novel pays particular attention to what Jim sees, especially the quality of color and light on the island. Treasure Island looks drab, lifeless, and generally unwelcoming, far from the lush landscape one usually associates with Caribbean islands.
Moments later, Jim thinks to himself:
My heart sank, as the saying is, into my boots; and from that first look onward, I hated the very thought of Treasure Island.
Instead of feeling excited upon his arrival, Jim feels apprehensive. He uses the saying "my heart sank" to describes his disappointment. In this moment Stevenson uses a metaphor; Jim's heart is not literally falling out of his chest and into his shoes, but his unhappiness is so strong that it feels like a physical force. Stevenson uses this figurative language to make the intensity of Jim's emotions more relatable to the reader. The chagrin Jim feels also hints at the danger and violence that befalls him and the other men once they arrive on Treasure Island—an example of foreshadowing.
In the beginning of Chapter 15, Jim sees a strange figure "flitting" in the woods "like a deer" and becomes frightened. However, remembering his pistol, Jim's fear begins to subside. He then uses a metaphor to describe his newfound confidence:
As soon as I remembered I was not defenseless, courage glowed again in my heart; and I set my face resolutely for this man of the island, and walked briskly towards him.
In the above passage, the abstract concept of courage is given a physical quality. Jim likens courage to a source of light and warmth in his body that gives him strength, wisdom, and power. Once he feels this new sense of power, Jim is able to move forward to face his fear of the stranger. This stranger importantly turns out to be Ben Gunn, a marooned member of Captain Flint's crew who eventually leads Jim and the other men to Captain Flint's buried treasure.
Stevenson uses this metaphor to make Jim's transformation more palpable to the reader. It is a crucial moment in the narrative, as it represents Jim's newfound maturity. Although fear almost stops him from taking action, Jim realizes he must adopt a courageous attitude in order to survive. Jim's decision to walk towards Gunn represents a shift towards adulthood. Jim begins to act for himself; although he is at times impulsive, his quickness of spirit allows him to sabotage the mutineers and prevent Captain Flint's treasure from falling into the wrong hands.
In Chapter 32, Jim and the pirates realize they are close to finding Captain Flint's elusive buried treasure. As the pirates approach the spot on the map where the treasure supposedly lies, the novel uses a metaphor to describe the intensity of their desire:
Their eyes burned in their heads; their feet grew speedier and lighter; their whole soul was bound up in that fortune, that whole lifetime of extravagance and pleasure, that lay waiting there for each of them.
As the pirates's excitement for buried treasure grows, they appear to physically transform in front of Jim's eyes. It is as if greed is a physical force that overtakes them. They move speedily ahead, focused entirely on the fortune ahead of them. The physical changes Jim describes aren't literal; Stevenson uses a metaphor to describe the pirates' greed and make their hunger for treasure palpable to the reader. Most of the time the pirates are described as unorganized, drunk, and bumbling. Treasure seems to be the only thing the pirates take seriously.
This is a dramatic moment in the narrative; the entire plot of Treasure Island, after all, is structured around finding Flint's treasure, and the treasure's existence is a source of motivation for almost all of the characters. However, through the plot's events, Stevenson makes clear that an unbridled desire for wealth comes at a high price: destruction and death.