What metaphors are used in The Fortune of War by Patrick O'Brian?

The story itself is a literal and metaphoric narrative on escape. The basic plot of the middle narrative arc involves an escape from imprisonment and possible execution. Indeed, nearly all of the events between the capture of HMS Java and the victory of HMS Shannon are focused on Aubrey's and Maturin's escape from America. At first, escape is only a nebulous ideal and Aubrey rather waits for parole and exchange while he recuperates. As Maturin's physical safety becomes precarious, however, escape becomes increasingly important. Much of the plot during this segment concerns an overly-complex escape planning carried on by George Herapath and, to some extent, by Aubrey. The plan rapidly becomes ridiculous and in the execution is completely collapses. Fortunately, Michael Herapath steps in and simply leads the escaping Aubrey, Maturin, and Villiers to a ship.