David Bushnell, an American inventor at the time of the American Revolution, is best known for designing the first submarine for war. His Turtle (pictured at right) was an egg-shaped, one-man vessel that was not entirely successful in its Sept. 1776 debut: the pilot tried, but failed, to attach a bomb to the hull of a British warship.

His pioneering experiments with sea mines are not as well known today, but they received a good deal of attention at the time. Shortly after Christmas in 1777, Bushnell set afloat a collection mines at Bordentown, NJ, 26 miles upriver from a British fleet at Philadelphia. The mines were kept afloat by kegs and were spring-triggered to detonate upon impact. As they drifted down river, two boys detonated one keg, while the crew of a civilian barge set off another. That was enough to alert the British, who set orders to fire upon any kegs floating downstream. Francis Hopkinson farcically recounted the "battle" between “the conquering British troops” and the “wicked kegs” in his song “Battle of the Kegs” set to the tune of Yankee Doodle. It was totally a hit with the American troops.

The Connecticut Water Machine Versus the Royal Navy (American Heritage)

(Turtle drawing, and other information on historical submarine technology, from the U.S. Chief of Naval Operations' Submarine Warfare Division)