Note: The n-stem suffix -din-, -dō is presumed to have been originally applied to stative verbs such as torpēre. It is directly comparable to the suffix in Greek algedon-, algedṓn "pain, suffering," derived from algéō, algeîn "to feel pain." In Latin the -ē- of the verb was taken as part of the suffix, which was then applied directly to adjectives, the resulting nouns often denoting undesirable or unpleasant states (as gravēdō "head cold, oppressive feeling," dulcēdō "sweetness, pleasantness, itch, irritation," putrēdō "rottenness"; compare as later formations albedo, flavedo). — The application of the word torpedo "electric ray" to submarine warfare dates to the early years of the American Revolution. The Pennsylvania-born inventor David Bushnell (1740-1824 or 26) developed a small submersible vessel in 1776, which was used in an unsuccessful assault on a British ship in New York harbor on September 7th of that year. The physician James Thacher recorded this event in his journal for October: "By some gentlemen from head-quarters, near New York, we are amused with an account of a singular machine, invented by a Mr. D. Bushnell of Connecticut, for the purpose of destroying the British shipping by explosion …Mr. Bushnell gave to his machine the name of American Turtle or Torpedo" (Military Journal of the American Revolution, [Hartford, CT, 1862], pp. 62-63). Bushnell appears to have given the name "torpedo" to his submarine, rather than solely to the time-detonated powder magazine that was meant to be screwed into the hull of a ship below the waterline. In a description of the boat and powder magazine sent in a letter to Thomas Jefferson in October, 1787, Bushnell used neither "turtle" nor "torpedo." (The letter was published as "General Principles and Construction of a Sub-marine Vessel" in Transactions of the American Philosophical Society, vol. 4 [1799], pp. 303-12.) In 1777 Bushnell experimented with floating mines—powder kegs set off by a spring-released flintlock—but these too failed to damage a British vessel. Probably not unconnected to Bushnell's "torpedo," the same word was used by Robert fulton in the early nineteenth century to refer to underwater explosive devices of his own design, in letters and a pamphlet Torpedo War, and Submarine Explosions (New York, 1810); Fulton believed that submarine mines, his "torpedoes," would effectually end aggressive naval warfare and ensure freedom of the seas. With the development of the self-propelled torpedo by the British engineer Robert Whitehead in 1866, the word torpedo began to be applied solely to such devices, with submarine mine or a similar term reserved for stationary explosive devices.