David Bushnell (1742-1824) built the first man-propelled submarine boat with a wooden magazine containing gunpowder and a clock mechanism for igniting it at any particular time. Although he was not successful in his attempts to destroy British ships during the American Revolution, he is recognized as the father of the modern submarine.

David Bushnell was a descendant of Francis Bushnell, an Englishman who joined the New Haven Colony in 1639 and subsequently helped to found Guilford, Connecticut. David was born on his father's farm in Saybrook, Connecticut. The home was located in an extremely secluded portion of the township and here young Bushnell grew up, helping his father with the farm duties, devoting his leisure moments to reading, and shunning all society. When he was twenty-seven his father died, and, as his mother had died some years before, the farm descended to David and his brother. David immediately sold his inheritance, moved into town, and began to prepare for college. He secured as tutor, the Reverend John Devotion, pastor of the local Congregational church. Two years later Bushnell entered Yale, and completed the four-year course in 1775.

Bushnell's Turtle

On one occasion, as a result of a discussion with members of the faculty, Bushnell demonstrated the fact that gunpowder could be exploded under water. This is thought to have suggested to him the idea of a submarine mine or torpedo. Apparently he gave much time and attention to this during his college years, for in 1775 he completed at Saybrook a man-propelled submarine boat on the outside shell of which was attached a wooden magazine containing gunpowder and a clock mechanism for igniting it at any particular time. The boat, built entirely of heavy oak beams, had the shape of a top. In fact, its exterior appearance was said to resemble a structure that would result from joining together the upper shells of two turtles and weighting the whole so that the tail end pointed downward and the head skyward. For this reason it was called "Bushnell's Turtle." The vessel was equipped with a vertical and horizontal screw propeller and rudder, operated by hand from the interior. It also contained a water gauge to indicate the boat's depth; a compass for direction, lighted up with phosphorus; a foot-operated valve in the keel to admit water for descending; and two hand-operated pumps to eject the water for ascending. The magazine, or torpedo, was located above the rudder and was connected by a line with a wooden screw, turned from within, which could be driven into a ship's hull. A further arrangement was contrived so that as the submarine moved away the clockwork in the mechanism was set in motion, having been previously set to ignite the charge at a certain time, the maximum being twelve hours. Bushnell successfully demonstrated his idea to the governor and Council of Safety of Connecticut who approved of his plan and suggested that he proceed with further experiment if necessary, with the expectation of a proper public reward.

During 1776-77 Bushnell attempted to blow up British ships but was never successful, owing entirely to his inability to obtain a skilled operator, he personally being too frail. Attempts were made in Boston Harbor; off Governor's Island, New York; and in the Delaware River above Philadelphia. After the failure at Philadelphia, in December 1777, Bushnell gave up further attempts amidst general popular ridicule, although today he is recognized as the father of the submarine.

Commanded Corps of Engineers

Bushnell's inability to prove the merits of his invention in actual warfare did not entirely discredit him. When General Washington organized companies of sappers and miners in 1779, Bushnell was made a captain-lieutenant. He was promoted to captain in 1781, and was stationed at West Point in command of the Corps of Engineers on June 4, 1783. In November of that year he was mustered out of service, receiving the commutation of five-years' pay in lieu of one-half pay for life.

During the following ten or twelve years it is believed that he went to France. In 1795, however, he appeared in Columbia County, Georgia, as a schoolteacher, under the name of Dr. Bush. He lived with a fellow soldier, Abraham Baldwin who was the only person who knew his real identity. Through him Bushnell became head of a private school. Several years later he settled in Warrenton, Georgia, and began the practice of medicine which he continued until his death in 1824, at the age of eighty-four. As far as is known he never married.

Further Reading

• Abbot, Lieut.-Col. Henry L., Beginning of Modern Submarine Warfare, 1775.
• Dexter, F. B., Biographical Sketches of the Graduates of Yale College, vol. III, 1903.
• Howe, Henry, Memoirs of the Most Eminent American Mechanics, 1844.
• White, George, Historical Collections. of Georgia, 3rd ed., 1855, pp. 406-09.
• American Journal of Science, April 1820.
• Connecticut Historical Society Collections, vol. II, 1870.
• Transactions of the American Philosophical Society, vol. IV, 1799, No. 37.