Capt. Jack Aubrey: This is the second time he's done this to me. There will not be a third.
Capt. Jack Aubrey: England is under threat of invasion, and though we be on the far side of the world, this ship is our home. This ship *is* England.
Capt. Jack Aubrey: To wives and sweethearts - may they never meet.
Dr. Stephen Maturin: Jack, I fear you have burdened me with a debt I can never fully repay.
Capt. Jack Aubrey: Nonsense! Name a shrub after me. Something prickly and hard to eradicate.
Dr. Stephen Maturin: A shrub? Nonsense! I shall name a new species of tortoise after you: Testudo Aubreii!
Chosen answer: The flag is a signal flag, and is probably meant to signal that the ship is a whaler or engaged in fishing operations. Such flags were part of an international code, which, with some modification, is still in use today. (The flag is similar to the modern-day "Foxtrot".)