The relationship of the ship’s center of gravity and center of bouyancy also has a great effect on stability, so design of the hull shape and weight distribution is a major concern for marine architects. During the days of sail, not only weight and hull design had to be considered, but wind forces on the rig as well. Ships are rigidly designed to survive and prosper in a chaotic and hostile environment, while performing a specific mission. That’s why I love them.

Ballast water has become an environmental issue, because ships traveling between the seas can transport spores, plankton, larvae, eggs and other microscopic marine organisms into places were they don’t belong as ships pump ballast to get into shallow harbors, or as they load and unload cargo.

When I was in California, there was some concern that the Dungeness Crab fishery was being threatened by the accidental introduction of the aggressive Atlantic Blue Crab, probably in ships that had gone through the Panama Canal. Both make for delicious eating, but both play a major role in their respective ecosystems. And I understand some of the pests now infesting the Great Lakes were brought in via ship ballast.