David Bushnell
David Bushnell was an American inventor and patriot, best known for creating the first operational submarine, the Turtle, during the American Revolutionary War. Born in 1732 in Saybrook, Connecticut, Bushnell's early fascination with gadgets and construction led him to study at Yale, where he excelled in science and mathematics. After graduation in 1775, he designed and constructed the Turtle, an innovative craft capable of underwater navigation and armed with explosives meant to disrupt British naval forces blockading New York City.
The Turtle was notable for its unique design, which included a wooden cockpit and a propeller-driven propulsion system, along with the ability to deploy explosives against enemy ships. Despite his efforts, Bushnell's attacks proved unsuccessful, primarily due to unforeseen circumstances rather than the submarine's capabilities. Following the war, Bushnell lived in relative obscurity, relocating to Georgia and adopting a new identity.
Bushnell's contributions to naval warfare and submarine technology were significant; he pioneered techniques such as using pumps for ballast control and developing waterproof explosives. Though he is sometimes referred to as the "father of submarine warfare," many of his concepts were influenced by existing European designs. Nevertheless, his work laid the groundwork for future innovations in submarine technology, with elements of his designs echoing in modern submarines.
David Bushnell
American engineer
- Born: August 30, 1742
- Birthplace: Saybrook, Connecticut
- Died: 1824
- Place of death: Warrenton, Georgia
During the Revolutionary War, Bushnell designed and built the first attack submarine in the history of warfare. While it failed in its original objective against the British navy, it would have a significant impact on submarine technology.
Primary fields: Military technology and weaponry; naval engineering
Primary invention: Bushnell’s submarine
Early Life
David Bushnell was born and raised on a farm near the town of Saybrook, Connecticut. His Bushnell ancestors had emigrated from England in 1639, just over a century before he was born. Between chores on his father’s hardscrabble land, young Bushnell read voraciously about all kinds of gadgets and how they worked. Construction techniques also fascinated him. He hoped to deepen his understanding of science and technology at nearby Yale College (later Yale University), but lack of funds made this unattainable until he inherited a modest bequest upon his father’s death.
When Bushnell finally reached the Yale campus in 1771, he was, at the age of thirty-one, by far the oldest in his class. He excelled in science and mathematics to the extent that his science professor allowed him to conduct unsupervised experiments. Bushnell had become intrigued by gunpowder for its potential military uses at a time when relations between the American colonies and the British mother country were coming under increasing strain. Finally, after many attempts, Bushnell managed to detonate underwater two pounds of gunpowder sealed in a wooden keg and detonated by a waterproof fuse. Bushnell had next to find the best means for deploying this weapon, as necessary, against the British navy.
In early 1775, Bushnell’s senior year, the intensifying dispute between the colonies and England had come to flashpoint with skirmishes at Lexington and Concord in Massachusetts. Alienated by British taxation policies and by arbitrary interventions in colonial affairs, local militias were mobilized and mounted a full rebellion against their British rulers.
Life’s Work
Immediately following graduation in June, 1775, Bushnell returned to the family homestead in Saybrook. Over the next year, he built and tested at his own expense a small submarine that he had designed while still at Yale. He found locally most of what he needed. Most important, he began with two large slabs cut from the trunk of an oak tree. Craftsmen then hollowed out these pieces and trimmed them to match like mirror images. They were then fitted together and sealed with tar along the seam where they came together. A band of iron was nailed to the seam to complete the waterproofing of the craft. The result was an oval-shaped wooden cockpit or cabin that Bushnell dubbed the Turtle because of its resemblance to two fused tortoise shells standing on end.
The Turtle’s cabin measured a little over seven feet long, six feet high, and three and a half feet wide at the middle. These dimensions allowed barely enough room for one operator, who entered through a small hatch at the top of the cabin. He sat on a wooden beam facing a whole array of devices such as valves, peddles, pumps, and shafts necessary to run the submarine. Fixed outside on the submarine’s back was a wooden keg with a capacity of up to 150 pounds of gunpowder. By the summer of 1776, the Turtle was fully tested and ready. The American military commander George Washington had learned of Bushnell’s secret project and authorized its use against the British fleet that was blockading New York harbor.
American forces defending New York City were surrounded by a veteran British army supported by warships anchored nearby. Naval cannons from the harbor regularly raked the American positions. British strategy was to take New York City and overrun the Hudson River Valley, which would split the American colonies in two. General Washington wanted the Turtle to disrupt the blockade of New York harbor by harassing the enemy fleet.
The Turtle was secretly ferried down the Connecticut River from Saybrook and poised for a strike at the British ships. However, on the eve of the attack, in August, 1775, David’s brother, Ezra, fell ill with a high fever and was incapacitated for several weeks. The submarine was withdrawn, pending the training of a substitute pilot. David Bushnell himself lacked the physical strength to operate it.
A replacement named Ezra Lee was found and given accelerated training. By the evening of September 6, 1776, the Turtle, piloted by Lee, departed Manhattan Island and made its way slowly toward the enemy fleet. Using a pedal to work a propeller, Lee peddled the Turtle slowly toward its target, the HMS Eagle, the flagship of the fleet. The Eagle was a formidable frigate with its sixty-four guns pointed in all directions. To sink or damage it would have been a severe blow to British morale.
Half-submerged, the Turtle approached the Eagle while carefully observing it through a small conning tower. Lee then fully submerged by taking on water by means of a foot valve. Next, he maneuvered and stabilized the Turtle under the Eagle’s hull by using a horizontal propeller with one hand while steering with the other. A long, wood screw located outside at the top of the submarine was to drill a hole in the Eagle’s hull by turning into it. The 150-pound keg of gunpowder on the back of the submarine would then be drawn to the Eagle by an attached rope. The charge was to be fixed in the drill hole, and the rope would automatically draw the explosive container until it rested hard against the hull. An improvised clockwork timer would be set to detonate a fuse to the gunpowder once the Turtle was well clear of the ship.
The operation worked as planned until it came to drilling the hole. Unknown to Bushnell, the Eagle’s hull had a reinforcing iron bar at the point where the wood drill tried to penetrate. After several maneuvers to find vulnerable places on the hull, Ezra Lee, exhausted from his long ordeal, aborted the mission as dawn approached and headed back to shore. En route, he jettisoned the keg of gunpowder that exploded harmlessly in the bay.
Subsequently, Bushnell attempted two other attacks, neither of them successful. The failures were not due to the submarine’s performance but related mostly to poor judgment and simply bad luck. Bushnell spent the rest of the war designing improved sea mines. His life after the war is something of a mystery, as he disappeared. As became clear only after his death in 1824, Bushnell had gone to rural Georgia, changed his name to David Bush, and lived out his days as a schoolteacher and physician. He never married.
Impact
The Turtle was far more than a curious fantasy of an eccentric and secretive tinkerer. Bushnell built a fully functioning submarine replete with ingenious devices and capable of delivering a lethal charge of explosives to seaborne targets. Due to Bushnell’s work as an American patriot during the Revolutionary War, the “water machine” became more widely recognized as a potentially deadly new weapon of naval warfare.
Bushnell was an innovator. He was the first, for example, to successfully use pumps to fill empty ballast tanks, which allowed the submarine to submerge and resurface. This principle is still in use today, as is his idea of the screw propeller to guide the submarine. Also of significance was Bushnell’s discovery of how to make waterproof powder kegs that could be detonated with a waterproof fuse either on or under the water. Here can be found the genesis of the sea mine or torpedo so well known in modern naval operations. Finally, Bushnell is credited with constructing the first documented example of a submarine actually used for combat operations. Robert Fulton’s celebrated Nautilus submarine, completed in 1801, sported a conning tower, screw propellers for propulsion, and a procedure for detonating explosives against ships’ hulls.
Frequent descriptions of Bushnell as the “father of submarine warfare” need qualification. Many of his ideas and techniques regarding the submarine came from European sources. Nonetheless, Bushnell skillfully adapted these materials to his own purposes. He was an innovator in several respects as well as a transmitter of submarine lore to future generations.
Bushnell’s lack of success in his time has been described as a kind of “fertile failure” in that what he achieved would resonate. Despite the vast differences between the submarine technology of the eighteenth century and that of the present, with its nuclear-powered submarines and their nuclear missiles, there is still a sense in which modern submarines remain lineal descendants of the Turtle.
Bibliography
Diamant, Lincoln. Dive! The Story of David Bushnell and His Remarkable 1776 Submarine (and Torpedo). Fleischmanns, N.Y.: Purple Mountain Press, 2003. A brief but lively overview of the Turtle episode. Especially effective in the use of direct quotes and contemporary documents relating to the event. Illustrations, bibliography.
Lefkowitz, Arthur S. Bushnell’s Submarine: The Best Kept Secret of the American Revolution. New York: Scholastic, 2006. Written with a “you-are-there” sense of immediacy. Occasional one-page side discussions on related topics add a valuable dimension. Illustrations, index.
Parrish, Thomas. The Submarine: A History. New York: Viking Press, 2004. One of the best general histories of submarines to date. Traces the transformation of the submarine from a kind of exotic curiosity (Bushnell’s Turtle in 1776) to the nuclear submarine of 2000, a core element of modern naval warfare. Illustrations, bibliography, index.
Roland, Alex. Underwater Warfare in the Age of Sail. Bloomington: Indiana University Press, 1978. Traces the history of the submarine from the early seventeenth to the later nineteenth centuries, including the U.S. Civil War. Chapters 6 and 7 relate Bushnell’s achievement to the broader history of submarine technology and warfare. Disputes the originality of Bushnell’s submarine. Illustrations, bibliography, index.
Wagner, Frederick. Submarine Fighter of the American Revolution: The Story of David Bushnell. New York: Dodd, Mead, 1963. Still the only full-scale scholarly biography of Bushnell. Efficiently builds suspense toward the climactic event of the Turtle’s attack on the English flagship. Illustrations, bibliography.