TURTLE – A Revolutionary Submarine

TURTLE  – A Revolutionary Submarine
George Pararas-Carayannis

A CHAPTER of early American maritime history that has often been overlooked is that of early submarines and, in particular, the story of the first American submarine in the War of Independence in 1776, with the American Revolution in full swing.In the summer of 1776, the British controlled the harbor of New York with a powerful fleet. It became necessary for the Americans to do something to remove the sea blockade.

David Bushnell – the Designer and Builder of the Revolutionary Submarine

David Bushnell (1742 – 1842) of Saybrook, Connecticut, a Yale graduate who also had invented the time bomb, was considering many options on vessels that could transport and attach timed explosives to destroy British warships. Finally, he decided on building and using a submarine for the delivery of a bomb to the enemy warships.

However, there were many engineering and design problems which he had to solve with the limited technology of that time. He had to build a watertight, pressure-proof hull, which would provide vertical and horizontal propulsion, that would have vertical stability, variable ballast, steering controls, and a weapons-delivery system, to name a few.


 Construction of the Turtle 

The submarine Bushnell designed and which finally built he named “Turtle”. because it was shaped like one. The sub’s hull was constructed with curved-shaped oak timbers, caulked at the joints,  bound with iron straps and covered with tar. The egg-shaped, one-person submarine was about 7 feet long inside, 4 feet wide, and 8 feet from its keel to the top of its conning tower. The submarine’ s buoyancy was maintained by pumping water in/out of the hull via a hand pump. 

Since it had no periscope, the Turtle’s conning tower contained six glass ports in the circular casting. The interior of the vessel included equipment which was the forerunner of equipment to be used in later-day submarines. There was a depth gauge for indicating depth below the surface and a compass for steering. These were marked with a phosphorescent “Foxfire” so their dials could be read in the dark. Other innovations included a crank for hand operation of the propeller; a tiller for operating the rudder; 700 pounds of lead ballast, 200 pounds of which could be quickly lowered about 50 feet in case of emergency. The design included an immersion chamber for flooding when additional ballast was desired as well as two brass forcing pumps for forcing water out of the immersion chamber.  

The breathing air supply lasted only about 30 minutes and thus two tubes were included that passed through the conning tower hatch for use in obtaining fresh air when near the surface. this was done frequently, for the air soon became foul with carbon dioxide when the submarine was in the submerged condition.

When tested, the submarine bobbed like a cork in rough surface winds and seas even though she had lead weights at the bottom. In this hand-and foot-operated contraption, one person could descend into the sea by operating a valve to admit water into the ballast tank and to ascend with the use of pumps to eject the water. Two flap-type air vents at the top opened when the hatch was clear of water and closed when it was not. When in surface trim, its metal conning tower protruded about 8 inches out of the water, making it difficult to track but difficult to get air if there was significant wave action. Finally, the submarine was also designed to attach a keg of powder, with a timed fuse, to an enemy ship’s hull.

The submarine’s builder David Bushnell was originally assigned the task of piloting the Turtle and try to sink HMS Eagle,  the 64 guns British warship, which was anchored in New York Harbor at the time. However, he was unable to conduct the operation because of illness. Instead,  Sergeant Ezra Lee, an army volunteer was assigned the task.

Part of this process was to bore through the hull with a hand-cranked drill.

Who was  Ezra Lee 

Ezra Lee (August 1749 – October 29, 1821) was a Colonial soldier in the American Revolution, who made naval history as the first person to operate a US submarine in battle – the Turtle. Lee was born in Lyme, Connecticut. In August 1776 Lee was selected by his brother-in-law Brig. General Samuel  Holden Parsons, also of Lyme, as one of several volunteers to learn to operate and commandeer the “Turtle” in New York Harbor in an attempt to torpedo a British warship. General George Washington authorized an attack on the British Admiral Richard Howe’s flagship HMS Eagle, then lying in New York harbor, Lee was chosen to operate the “Turtle” for that purpose. 

Propelled by Pedals and Cranks

The submarine was capable of carrying one person who sat upright on a seat resembling that of a bicycle. Turtle s supply of air, in the submerged state, would last about 30 minutes. Located at the bottom of the submarine were a lead weight for ballast and an aperture with a valve to admit water for descent. Two brass forcing pumps served to eject the water from within for ascent. In front of the seated operator was a screw type oar for propelling the vessel forward or backward while, above him, there was a similar oar for ascending, descending, or maintenance of depth. The rudder, located behind the operator, was operated by foot. Furthermore, Turtle was equipped with a depth gauge, a compass to direct the course, and a ventilator to supply the vessel with fresh air at the surface.

The Turtle was built at Saybrook, Connecticut, by David Bushnell and his brother, Ezra. After the vessel’s completion in 1775, they tested her in the Connecticut River. Unfortunately, the tests indicated that Turtle was not ready to be used against the ships of the British fleet which were blockading Boston Harbor. Problems ranged from the failure of a ballast pump to the need for phosphorescent fox-fire to light the interior of the submarine.

The Turtle’s Attack on the Eagle

In the spring of 1776, Turtle was ready to be transported by a sloop to Boston to fight the British fleet. By that time, however, the news was received that the British had broken off their blockade there and had moved their ships north to Halifax, Nova Scotia. Since there were still British warships in New York Harbor, Turtle was secretly transported there and stationed at The Battery in Manhattan, which was still under the control of America’s General Putnam, with his army of about 9,000 men.

The waters of New York Harbor, between The Battery and Governor’s Island, had complex patterns of currents and tides, presenting navigational problems completely different from those in the Connecticut River. Ezra, who operated Turtle, trained through June, 1776 until he and David were satisfied that he was familiar with the tidal conditions. General Putnam gave them permission to attack the 64-gun British warship Eagle at the first opportunity.

The opportunity presented itself on July 12 when Lord Howe, the commander of the British naval forces, anchored Eagle off Staten Island, but one adversity followed another. As mentioned, Ezra Bushnell became ill with fever and was unable to operate Turtle. Since General Putnam and George Washington agreed that the submarine should be tried against the enemy, Sergeant Ezra Lee of Old Lyme, Connecticut was selected from a group of volunteers to operate her. For the next two months, Ezra Lee trained intensively.


A Vain Attempt

Near midnight of September 6, the moon and the tide were favorable for an attack. The Turtle was towed by a small rowboat toward Eagle. Halfway to Staten Island, the rowboat stopped, and Lee entered Turtle and fastened the hatch over his head. For the first time in the history of naval warfare, a submarine was engaged in a war against an enemy ship.

HMS Eagle at the Port of New York

After diligent pedaling, Lee brought Turtle on the side of Eagle. After taking some ballast, he submerged completely. When he thought he was under his target, he pumped out a small quantity of water from the ballast tank, until a jarring bump indicated he was beneath Eagle. For the next few minutes, Lee vainly tried to attach a torpedo to her hull. When the air in his little cabin was almost used up, Lee had no choice but to abandon his attempt and surface. After replenishing the air in the cabin and resting, he again descended underneath Eagle to try to affix a torpedo on her hull. He failed. A metal plate covered the area where he was trying to drill. Having consumed his air, he was forced to abandon his goal and surface.

An Inglorious Victory

Lee was exhausted, and the outgoing tide threatened to take the small craft out to sea. Desperately, he ejected all the ballast water and began pedaling with all his remaining strength. With the ballast water pumped out, one third of Turtle’s hull stuck out of the water, making it clearly visible in daylight. In fact, as dawn broke, two British soldiers set out from Governor’s Island in a patrol skiff to investigate the floating object. To divert the patrol and to lighten his craft, Lee released a time operated 250-pound (250 pounds = 113 Kilograms) torpedo and, picking up speed, reached The Battery and safety.

Soon thereafter, the torpedo exploded, shattering the silence of the early morning and arousing the British fleet. Quickly, the British raised their anchors and hurriedly moved their ships to the safer waters of lower New York Bay.

The Turtle attempting to attach a torpedo on HMS Eagle’s hull.

The Turtle was equally unsuccessful in two subsequent efforts against Eagle and another British frigate. In both instances, the tides and tricky currents of New York Harbor frustrated the ventures. In an effort to move the submarine to areas where attacks could occur under more favorable conditions, Bushnell loaded Turtle aboard a fast sloop, hoping that the sloop could slip unnoticed past the British into Long Island Sound and back to Connecticut. A British frigate discovered the sloop, however, and, according to the British, sank her and her precious cargo. The Americans claimed that she was dismantled and moved inland to keep her out of enemy hands. Whatever the final fate of Turtle, as the first American war submarine, she came to a premature end and closed a not-so-glorious chapter of maritime history in the American Revolution.


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