Maturin writes in his diary that he is enjoying the Mediterranean voyage, but is frustrated with sailing past so many famous locations from classical literature without stopping. Nevertheless, he is happy with the animals that he is able to observe from the ship, including birds, sharks, and turtles. Maturin is still concerned with the animosity between Aubrey and Dillon, who are civil when aboard the ship, but might kill each other when they reach land. Maturin recalls Aubrey‘s explanation about his ambition to become a post-captain. If Aubrey becomes a post-captain, he actually has the rank of captain, whereas he is currently only called a captain out of courtesy.

Aubrey invites some of the officers and the young Henry Ellis, the new boy, to dine with him, but Maturin notices an approaching ship as they eat. It turns out to be the French frigate Dedaigneuse, which has superior firepower but travels more slowly. Aubrey goes to ensure that the Sophie is sailing at its fastest speed to outrun a fight. Henry Ellis falls overboard, and they are forced to delay 10 minutes while he is brought back aboard. He appears to be dead, but Maturin revives him by hanging him upside down and blowing smoke into his lungs.