[63] Mr. Woodcroft observes that “this vessel might, from the simplicity of its machinery, have been at work to this day with such ordinary repairs as are now occasionally required for all steamboats,” p. 53; and, again, “thus had Symington the undoubted merit of having combined for the first time those improvements which constitute _the present system of steam navigation_.” [64] Patented 23rd August, 1780. An invention in which the reciprocating motion of a beam acting on a connecting rod turns a wheel. Woodcroft, “Marine Propulsion,” Part I. p. 32. [65] It seems important to record that the success of Mr. Symington’s engine consisted mainly in this: that, after placing in a boat a double acting reciprocating engine, he _attached his crank to the axis of the paddle-wheel_, a combination on which, as Mr. Woodcroft justly observes, “there has been no improvement even to the present time, either in this or in any other country.” The power thus applied secured rotary motion without the interposition of a lever or beam. Mr. Symington might fairly claim, as he does in his patent of October 14th, 1801, that “the principle of this invention comprehends any species of machinery thus put in rotatory motion by a steam engine which may be made use of to navigate boats, vessels, or rafts.” [66] “Encyclopédie Moderne,” Paris, 1855, art. “Vapeur,” p. 171. [67] See “Des Bateaux à Vapeur,” par Jouffroy (the son of the Marquis), pp. 13 and 17; and “L’Universel Dictionnaire Encyclopédique de la France,” Paris, 1845, vol. ix. p. 737. [68] Ibid., p. 737. [69] Stuart’s “Anecdotes of Steam Engines,” vol. ii. pp. 450 and 483. [70] “Elements of Experimental Physics,” Florence, 1796, quoted by J. Scott Russell on “Steam and Steam Navigation,” p. 238; also referred to nine years previously in “Lettere di Fisica Sperimentale,” di Seraffino Serrati; Firenze, 1787, 12mo., and quoted in “Biographie Universelle,” Paris, 1856, art. “Fulton.” [71] “Steam Navigation,” pp. 48-51. [72] 6th Report, p. 179. [73] See Brewster’s “Encyclopædia,” extracted from the _Columbian Magazine_, Philadelphia, vol. i., December 1786.