I have a scene in which my main character is shackled to a rowing bench on a galley. In short, the galley is sinking and he needs to get free fast. I was thinking of having the chain being a single cord running through say a bracket and ending with a shackle on each end that is attached to his wrists. My idea was to have him break or otherwise mangle one of his hands in a rage and slip it free of the shackle. Then he could run the chain out and be free even though his other hand is still shackled. My question is if this is feasible and if so would the average person be able to then swim to shore after effectively breaking his own hand. If there is another method of getting free that doesn't involve such a gruesome action I would prefer it. He doesn't have time to wear down the chain or wood or anything like that. He was not even trying to get free until a moment ago. Any ideas are appreciated.
Can you utilise the other rowers around him at all? When you have a group of strong, desperate men thrown into a panic for their lives, interesting things might happen... Or someone else could have been planning a revolt (make sure you foreshadow it beforehand)? Slave and similar uprisings were a significant problem at the time. Mangling a hand like that and then making him swim a distance with it, in a time when the setting of bones would have been rudimentary at best, is likely to result in a longterm injury that may leave him crippled for life, so unless you plan to work that into the story you're probably best off avoiding it.
