Gulliver's narration of his fourth voyage begins much as the others have. He uses a dry and matter-of-fact tone, and he offers a great deal of nautical detail. The style is deliberately prosaic. Swift is reaffirming Gulliver's unimaginative and credulous character. We can expect Gulliver to report what happens in Houyhnhnm land just as exactingly and as reliably as he does sailing dates, cargo information, and ports of call.
One other matter that might be noted before the adventure proper begins concerns the circumstances which have deposited Gulliver in the various foreign lands. Increasingly, these circumstances have become more serious. The sailors, in this section, maroon Gulliver out of treachery, malice, and ingratitude, whereas earlier he had been abandoned because of bad luck, fear, and greed. As Gulliver's mishaps become more threatening, the subject of each section becomes weightier.
Gulliver's description of the Yahoos displays one of Swift's most effective techniques: He describes the familiar in terms that are new. At first, the Yahoos seem familiar, but who, or what, they are is obscure. Then, with a jolt, Swift's point is obvious; the Yahoos are humans. Swift also captures the interest of his reader by posing a problem. He does not identify the Houyhnhnms as rational horses in this first chapter; therefore, the reader, like Gulliver, must try to solve the puzzle of who, or what, they are.
Gulliver describes the Yahoos as " . . . deformed . . . . Their heads and breasts were covered with thick hair . . . but the rest of their bodies were bare . . . . They had no tails and often stood on their hind feet . . . ." Then he adds, "I never beheld in all my travels so disagreeable an animal." The behavior of these animals is equally disgusting as Gulliver describes defending himself from them by drawing his sword and backing up to a tree for protection, but they then climb the tree and begin defecating on him. On the other hand, Gulliver's description of the horses, the Houyhnhnms, is almost idyllic: "The behaviour of these animals was . . . orderly and rational . . . acute and judicious." Indeed, it is a horse that rescues him from the Yahoos — not by any overt, physical action, but by simply appearing on the road — no physical action being necessary.
