'Hog' is a change in the shape of a wooden ship due to structural damage. After a ship has been around for a few years, things will inevitably break. A good ship's carpenter might be able to keep up minor repairs while at sea, but eventually the wood will rot, planks will come apart, deck beams will come loose, and frames will break. As the ship loses the ability to hold its shape, her bow and stern will droop, she will spread apart across the deck, and rise up slghtly amidships.

A hogged ship will not move through the water as quickly as a sounder ship, and will leak more. More to the point, the ship will have lost her graceful girlish figure. She will look, well, tired. Not shipshape.

Sound ship:

              
                   ||             || \           |o--._          \
                   |o             ||  \          ||\   `-._       \
                   ||\            ||  |          || )      `-._    \
                   || )           || /           ||/           `-._ \
                   ||/            ||/            |o                `.\
    _______        |o             |o             ||        ______.-======
   /       |_______||_____________||____________.''-------'       /
  (                                                             /
   \O  O    O    O    O    O    O    O    O    O    O    O     /
    \                                                         /
     \                                                       /
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Hogged ship:

         
                   ||             || \           |o--._          \
                   |o             ||  \          ||\   `-._       \
                   ||\            ||  |          || )      `-._    \
                   || )           || /           ||/           `-._ \
                   ||/            ||/            |o                `.\
                   |o             |o             ||           ____---__
   ___.----.    ___||_____.-------''-------._____||_.--------'   /   --       
  /        '---'           _    O    O    _    _    _    _      /
  \ -, -,   -,   O    O   `-             `-   `-   `-   `-     /
   \                                                          /
    \                                                        /
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When hauled out of the water, a hogged ship will probably show a noticeable chine at the turn of the bilge. A small boat can be repaired, but a large ship requires a substantial overhaul. In the past, this would have been economically infeasible, and the tired old girl would have been broken up for firewood. Large wooden ships are so rare today, that millions of dollars can be spent repairing them for their historical interest alone.