As Huck and Jim are on their way to Cairo, Jim tells Huck about how he is going work and save money so that he can buy his family back and they will be together again. He says that he would even be willing to steal his children to get them out of slavery. During this time, Huck starts to feel that he is doing something bad to Miss Watson by helping her slave to run away. He makes up his mind that he will go to shore and turn Jim in. Just before he leaves, Jim tells Huck what a good friend he is and tells him that he is the first white man who has ever kept a promise to him. Jim's words really make Huck think about what he is doing.
When he gets to shore, Huck comes across two slave hunters. Huck decides that he cannot betray Jim. When the slave hunters ask who else is on board the raft with him, Huck says that his father is on board and that he is suffering from smallpox. The slave hunters are afraid of getting sick themselves, so they give Huck $20 and leave.
In chapters 15 and 16, Huck is feeling caught between his friendship and feelings of compassion for Jim and the view that he has grown up with that slaves are property. He feels as though he is caught between two immoral decisions. No matter what he does, he feels guilty and as though he is betraying someone. When he decides that he cannot turn Jim in, we see that his conscience is stronger than what he has been taught by society.
Later Huck and Jim realize that they have managed to float right past Cairo, which is where Jim will find freedom. They have lost their canoe, so they can't paddle back upstream. Then their raft is hit by a steamboat. They both go overboard and are separated. When Huck is not able to find Jim, he swims to shore.