Bushnell later described the propeller in an October 1787 letter to Thomas Jefferson: "An oar formed upon the principle of the screw was fixed in the forepart of the vessel its axis entered the vessel and being turned one way rowed the vessel forward but being turned the other way rowed it backward. Turtle also has the distinction of being the first submarine used in battle. On the night of September 6, 1776, Sergeant Ezra Lee piloted Turtle in an attack on HMS Eagle in New York Harbor. One of the first practical and applied uses of a propeller was on a submarine dubbed Turtle which was designed in New Haven, Connecticut, in 1775 by Yale student and inventor David Bushnell, with the help of the clock maker, engraver, and brass foundryman Isaac Doolittle, and with Bushnell's brother Ezra Bushnell and ship's carpenter and clock maker Phineas Pratt constructing the hull in Saybrook, Connecticut. In 1771, steam-engine inventor James Watt in a private letter suggested using "spiral oars" to propel boats, although he did not use them with his steam engines, or ever implement the idea. At about the same time, the French mathematician Alexis-Jean-Pierre Paucton suggested a water propulsion system based on the Archimedean screw. In 1752, the Academie des Sciences in Paris granted Burnelli a prize for a design of a propeller-wheel. In 1693 a Frenchman by the name of Du Quet invented a screw propeller which was tried in 1693 but later abandoned. Robert Hooke in 1681 designed a horizontal watermill which was remarkably similar to the Kirsten-Boeing vertical axis propeller designed almost two and a half centuries later in 1928 two years later Hooke modified the design to provide motive power for ships through water. In 1661, Toogood and Hays proposed using screws for waterjet propulsion, though not as a propeller. Later, Leonardo da Vinci adopted the screw principle to drive his theoretical helicopter, sketches of which involved a large canvas screw overhead. A flying toy, the bamboo-copter, was enjoyed in China beginning around 320 AD.
It was probably an application of spiral movement in space (spirals were a special study of Archimedes) to a hollow segmented water-wheel used for irrigation by Egyptians for centuries. The origin of the screw propeller starts at least as early as Archimedes (c. 287 – c. 212 BC), who used a screw to lift water for irrigation and bailing boats, so famously that it became known as Archimedes' screw. Propellers can have a single blade, but in practice there are nearly always more than one so as to balance the forces involved. The innovation introduced with the screw propeller was the extension of that arc through more than 360° by attaching the blade to a rotating shaft. In sculling, a single blade is moved through an arc, from side to side taking care to keep presenting the blade to the water at the effective angle. The principle employed in using a screw propeller is derived from sculling.
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