American Turtle

Turtle (also called American Turtle) was the world's first submersible with a documented record of use in combat. She was built in Old Saybrook, Connecticut in 1775 by American David Bushnell as a means of attaching explosive charges to ships in a harbor. Bushnell designed her for use against British Royal Navy vessels occupying North American harbors during the American Revolutionary War. Connecticut Governor Jonathan Trumbull recommended the invention to George Washington; although the commander-in-chief had doubts, he provided funds and support for the development and testing of the machine.

Several attempts were made using Turtle to affix explosives to the undersides of British warships in New York Harbor in 1776. All failed, and her transport ship was sunk later that year by the British with the submarine aboard. Bushnell claimed eventually to have recovered the machine, but its final fate is unknown. Modern replicas of Turtle have been constructed; the Connecticut River Museum, the U.S. Navy's Submarine Force Library and Museum, the Royal Navy Submarine Museum and the Oceanographic Museum (Monaco) have them on display.

In the early 1770s, David Bushnell, a Yale College freshman and Patriot, began experimenting with underwater explosives. By 1775, with tensions on the rise between the Thirteen Colonies and Great Britain, Bushnell had practically perfected these explosives. That year he also began work near Old Saybrook, Connecticut on a small manned submersible craft capable of affixing such a charge to the hull of a ship. The charge would then be detonated by a clockwork mechanism that released a musket firing mechanism, probably a flintlock, adapted for the purpose. According to Dr. Benjamin Gale, a doctor who taught at Yale, the firing mechanism and other mechanical parts of the submarine were manufactured by a New Haven clockmaker named Isaac Doolittle.

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