Huck and Jim judge that they are three days out of Cairo, near the Ohio River. The pair plans to take a steamboat up the Ohio into the free States, where slavery is illegal and Jim can no longer be hunted. But a fog sets in, limiting Huck and Jim’s visibility. With Huck in the canoe and Jim in the raft, the two become separated, and Huck becomes lost. Huck hears whooping sounds, and thinking them Jim’s signal, he whoops back, but to no avail. Huck continues to drift, “lonesome,” and, at some point, takes a nap. When he wakes, Huck realizes how big the river is before spotting the raft in the distance. Huck and Jim reunite.
The free States are Jim’s beacon of hope as a place the laws of which preserve his freedom. They are also a symbol in the novel for freedom generally. However, at a crucial juncture, it is not slave-hunters, for example, who impede Huck and Jim progress to freedom, but rather nature, specifically the fog that separates Huck from Jim. Even though nature is not persecutory like society is, it is random, indifferent to human desires, and sometimes, as here, dangerous.
Huck asks Jim if he fell asleep and why Jim didn’t think to wake him. Jim says he is just grateful that Huck didn’t drown. Huck asks Jim if he’s been drinking, to which Jim, taken aback, responds that he hasn’t. Huck tells Jim that he must have been dreaming that the pair was separated, indeed, that there was any fog at all. Jim can’t believe it; he sits quietly for five minutes. At last he tells Huck he must have been dreaming, but that it was the most powerful, vivid dream he’d ever had.
Huck has tricked Jim before, but not about something so important as this. That he is inclined to trick Jim at all demonstrates Huck’s childishness, but it also demonstrates, more problematically, Huck’s callousness toward Jim, maybe the product of his belief that Jim is racially inferior to him. Huck doesn’t yet fully empathize with Jim.
Huck requests that Jim tell him all about his dream, which Jim proceeds to do. Jim even interprets the dream, saying that the whoops are warnings of bad luck, the tow-heads are troubles the pair is going to get into with mean people unless the two mind their own business, and that the river clear of fog is the free States.
Even though the fog occurred randomly and without malice, Huck’s lie, that Jim dreamed the fog, encourages Jim to think of it within a superstitious interpretive framework, not as random and meaningless but as meaningful.
Huck then asks what the leaves and rubbish on the raft mean, along with its broken oar. Jim realizes that Huck was tricking him all along. Jim hadn’t been dreaming at all. He and Huck really were separated, and there really was fog. Jim tells Huck that he was heart-broken thinking that Huck had died in the fog, and that he had cried and wanted to kiss Huck’s foot to see him safe and sound again. And Huck could only think about making a fool out of Jim with a lie and shaming him. When he hears all this, Huck is himself ashamed. At last, after working himself up to humble himself to a black person, Huck apologizes to Jim, and feels no regret.
Jim is angry at Huck not for lying, but for failing to imagine the consequences of his lies, and, more generally, for failing to imagine how he (Jim) experiences the world. Jim was worried to death for Huck, even like a family member would worry, but Huck can’t imagine that and sees only a cheap opportunity to trick Jim in the style of Tom Sawyer. But after Jim expresses how much he worried over Huck, Huck realizes how calloused he’s been, and, as he will later in the novel to an even greater extent, he treats Jim like the equal that he is. That Huck feels no regret for apologizing shows his willingness to cross the slave/white divide and to see Jim as a true human being.