Now that they're off the reef, Nemo seems to be making up for lost time, pushing the Nautilus to the limit.
The sub, Aronnax realizes, is headed for the Indian Ocean. After that, who knows? Maybe they're headed around the tip of Africa and down to the South Pole.
Nemo keeps busy by performing experiments on water temperature. In the course of their discussions, Nemo mentions to Aronnax that he's learned things about the Mediterranean. Aronnax thinks this must mean that Nemo heads to Europe—that is, civilization—sometimes. Ned, set on escaping, will be happy to hear that.
One day, the Nautilus seems to fall asleep. In the darkness, Aronnax realizes that they're surrounded by tiny, glowing sea creatures that light up the ocean around the sub. They float there for a while, and Aronnax, Ned, and Conseil enjoy the sights.
A couple of days later, Aronnax heads up on deck to look out at the sea. When the sailor comes up on board, he says a different phrase, and soon, Nemo appears on the platform with a telescope. He talks with the first mate and then begins walking the platform, ignoring Aronnax.
Nemo orders the pilot to speed up; soon, the first mate seems to see something. He hands the telescope to Nemo again. In a flash, Nemo seems to be filled with anger. But, just as quickly, he calms down.
He tells Aronnax that the time has come for him to follow one of the rules laid out in their agreement: he has to be locked up, along with Ned and Conseil, in the cell. (This isn't quite what they agreed too—they were supposed to be held in their own rooms but, well, Nemo's the boss.)
Nemo won't answer any of Aronnax's questions, and soon the doctor's in a cell with his companions. Lucky for them, lunch is on the table.
They eat quickly and then Land and Conseil fall into a deep sleep.
Aronnax realizes that they've probably been drugged, but he can't resist the urge to slumber.