Turtle from
Wikipedia
The Turtle (also called the American Turtle)
was the world's first submersible with a documented record of use in combat.
It was built in Old Saybrook, Connecticut in 1775 by American Patriot David
Bushnell as a means of attaching explosive charges to ships in a harbor.
Bushnell designed it 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 the 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 functional
replicas of the Turtle have been constructed; the Connecticut River Museum,
the Submarine Force Library and Museum, and the Royal Navy Submarine Museum
have them on display.
Development |
A cut-away full size replica of
the Turtle on display at the Royal Navy Submarine Museum, Gosport, UK |
..
This 19th-century diagram shows
the
side views of the Turtle. It incorrectly
depicts the propeller as a screw
blade;
as seen in the replica photographed
above and reported by Sergeant
Lee,
it was a paddle propeller blade |
In the early 1770s, Yale College
freshman David Bushnell 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 that would be 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, that had been
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.
Named for its shape, Turtle resembled a large
clam as much as a turtle; it was about 10 feet (3.0 m) long (according
to the original specifications), 6 feet (1.8 m) tall, |
and about 3 feet (0.9 m) wide, and consisted
of two wooden shells covered with tar and reinforced with steel bands.
It dived by allowing water into a bilge tank at the bottom of the vessel
and ascended by pushing water out through a hand pump. It was propelled
vertically and horizontally by hand-cranked propellers. It also had 200
pounds (91 kg) of lead aboard, which could be released in a moment to increase
buoyancy. Manned and operated by one person, the vessel contained enough
air for about thirty minutes and had a speed in calm water of about three
miles per hour (5 km/h).
Six small pieces of thick glass in the top of
the submarine provided natural light. Illumination while submerged was
provided by a piece of cork that gave off a fungus-powered bioluminescent
foxfire. During trials in November 1775, Bushnell discovered that this
illumination failed when the temperature dropped too low. Although repeated
requests were made to Benjamin Franklin for possible alternatives, none
were forthcoming, and the Turtle was sidelined for the winter.
Bushnell's basic design included some elements
present in earlier experimental submersibles. The method of raising and
lowering the vessel was similar to that developed by Nathaniel Simons in
1729, and the gaskets used to make watertight |
.
A diagram showing the front and
rear of the Turtle |
connections around the connections between
the internal and external controls also may have come from Simons, who
constructed a submersible based on a 17th-century Italian design by Giovanni
Alfonso Borelli.
Preparation for use
Drawing of a cutaway view of Turtle's
interior. |
Bushnell's work began to receive more attention
in August 1775, when Franklin was informed of it. Despite Bushnell's insistence
on secrecy surrounding his work, news of it quickly made its way to the
British, abetted by a Loyalist spy working for New York Congressman James
Duane. On November 16, 1775, a coded message to William Tryon, the last
royal governor of the Province of New York, brought Bushnell's work to
British attention. The details of the report were highly inaccurate, implying
that the Turtle was nearly ready to be deployed in Boston harbor against
the fleet that was part of the British siege effort there. In fact Bushnell
and his brother Ezra were still testing the machine in the Connecticut
River. In the spring of 1776, after the British withdrew from Boston, Bushnell
offered the submarine to General George Washington for use in the defense
of New York City. Washington agreed, and provided some funding to the inventor
to prepare the vessel for deployment.
In August 1776 Bushnell asked General Samuel Holden
Parsons for volunteers to operate the Turtle, because his brother Ezra,
who had been its operator during earlier trials, was taken ill. Three men
were chosen, and the submarine was taken to Long Island Sound for training
and further trials. While these trials went on, the British gained control
of western Long Island in the August 27 Battle of Long Island. Since the
British now controlled the harbor, the Turtle was transported overland
from New Rochelle to the Hudson River. |
Attack on the Eagle
General Washington then authorized an expedition
by the Turtle in the waters of New York Harbor. At 11:00 PM on September
6, one of the volunteers, Sergeant Ezra Lee, took the Turtle out to attempt
an attack on Admiral Richard Howe's flagship HMS Eagle. She was moored
off what is today called Governors Island, which is due south of Manhattan.
According to Lee's account, she was towed by rowboats as close as was felt
safe to the British fleet. He then navigated for more than two hours before
slack tide made it possible to reach the Eagle. His first attempt to attach
the explosive failed because the screw struck a metal impediment. A common
misconception was that Lee failed because he could not manage to bore through
the copper-sheeted hull. Bushnell believed that Lee's failure was probably
due to an iron plate connected to the ship's rudder hinge. When Lee attempted
another spot in the hull, he was unable to stay beneath the ship, and eventually
abandoned the attempt. Lee reported that British soldiers on Governors
Island spotted the submarine and rowed out to investigate. He then released
the charge (which he called a "torpedo"), "expecting that they would seize
that likewise, and thus all would be blown to atoms." Suspicious of the
drifting charge, the British retreated back to the island. Lee reported
that the charge drifted into the East River, where it exploded "with tremendous
violence, throwing large columns of water and pieces of wood that composed
it high into the air." It was the first recorded use of a submarine to
attack a ship; however, the only records documenting it are American. British
records contain no accounts of an attack by a submarine or any reports
of explosions on the night of the supposed attack on HMS Eagle.
According to British naval historian Richard Compton-Hall,
the problems of achieving neutral buoyancy would have rendered the vertical
propeller useless. The route the Turtle would have had to take to attack
HMS Eagle was slightly across the tidal stream which would, in all probability,
have resulted in Ezra Lee becoming exhausted. In the face of these and
other problems Compton-Hall suggests that the entire story was fabricated
as disinformation and morale-boosting propaganda, and that if Ezra Lee
did carry out an attack it was in a covered rowing boat rather than the
Turtle.
Aftermath
On October 5, Sergeant Lee again went out in
an attempt to attach the charge to a frigate anchored off Manhattan. He
reported that the ship's watch spotted him, so he abandoned the attempt.
The submarine was sunk some days later by the British as it sat on its
tender vessel near Fort Lee, New Jersey. Bushnell reported salvaging the
Turtle, but its final fate is unknown. George Washington wrote of the attempt
that it was "an effort of genius", but that "a combination of too many
things was requisite" for such an attempt to succeed.
In 1777, Lee used floating mines in an attempt
to destroy the British frigate HMS Cerberus, anchored in Niantic Bay. The
explosion was said to have killed three sailors and destroyed a prize schooner
anchored astern of the Cerberus, although it left the Cerberus undamaged.
In 1778 Bushnell floated mines down the Delaware River in an attempt to
destroy British ships off Philadelphia. The mines took longer to reach
the area than expected, and there was a report that two boys investigating
them were blown up. On January 5, 1778, one of the mines struck a British
barge, killing four men and raising the alarm. The British response, in
which virtually any piece of floating wood in the river became a target,
was lampooned in a ballad called "The Battle of the Kegs". |
Bushnell mines destroying a British
ship |
Replicas
In 1976, a replica was designed by Joseph Leary
and constructed by Fred Frese as a project marking the United States Bicentennial.
It was christened by Connecticut's governor, Ella Grasso, and later tested
in the Connecticut River. This replica is owned by the Connecticut River
Museum.
On August 3, 2007 three men were stopped by police
while escorting and piloting a replica of the Turtle within 200 feet (61
m) of the Queen Mary 2, then docked at the cruise ship terminal in Red
Hook, Brooklyn. The replica was created by New York artist Philip "Duke"
Riley and two residents of Rhode Island, one of whom claimed to be a descendant
of David Bushnell. The Coast Guard issued Riley a citation for having an
unsafe vessel, and for violating the security zone around the Queen Mary
2 |
Replica at the Connecticut River Museum |
|