In Chapter 9, the father and Fritz make a journey to the wreck of the ship, which is still stuck out on the reef. They want to bring back the animals that they had left there.
First, the family eats breakfast. The father makes a flagpole "with a piece of sail-cloth for a flag." The mother and younger sons are to let the flag fly as long as things are going well. They are to take it down if they need to signal the father and Fritz to return from the ship.
The two arrive at the ship safely, feed the animals, and add a sail to their boat. They signal to the family that they will be spending the night on the wreck of the ship, and then begin loading their little boat with supplies from the ship which they were unable to carry when they first fled from it. When night comes, they signal to their family on land that all is well, then go to sleep in their "tubs" (components of the smaller boat), which they feel is a safer place to sleep than on the ship itself.
Chapter 10 narrates the second day of Fritz and his father's errand to the ship. They wake, check that the family flag is still up, and eat breakfast. Then they spend two hours making a "swimming apparatus" for the livestock by tying empty barrels on either side of each animal. They put a leash on each animal, the ends of which they fasten to the back of their little boat. Then they set out for shore, "drawing our train after us."
On the way back to the island, they are nearly attacked by a shark, which Fritz shoots with his gun. After this they arrive safely at the island.
They are greeted joyfully by the other family members. Jack shows off the belt he made for himself using the skin of the jackal that Fritz had killed. Jack has also made spiked collars for the dogs by driving nails through strips of the jackal's skin.
The family then have supper, which consists of a ham that was just brought from the ship, and an omelet made of turtle's eggs.