Keelhauling
The common supposition is that keelhauling amounted to a sentence of either death by extreme torture, or minimally a physical trauma likely to permanently maim. The hull of the ship was usually covered in barnacles and other marine growth, and thus, keelhauling would typically result in serious lacerations, of which the victim could later suffer infection and scarring. If the victim was dragged slowly, his weight might lower him sufficiently to miss the barnacles, but this method would frequently result in his drowning. There was also a risk of head trauma from colliding against the hull or keel, especially if the ship was in motion.
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