[57] Caledonian Mercury, Evening Courant, and Advertiser.
[58] In the Patent Office Museum, London, there may still be seen, “the parent engine of steam navigation, made for Patrick Miller, Esq., and used by him on the lake at Dalswinton, 1788.” It consists of two small paddles, working one behind the other, to be fitted on the same side apparently of a small boat.
[59] From the narrative given by Mr. Smiles in his “Lives of Boulton and Watt,” it is certain that they discouraged what they considered “speculative” adventures. Both were written to, with requests that they would make engines for Mr. Miller, those constructed by Symington not having answered as well as was expected, and both declined to have anything to do with the scheme. (Smiles, p. 445.)
[60] “Woodcroft on Steam Navigation,” p. 54.
[61] “Encyclopædia Britannica” (eighth edition), vol. xx. p. 637.
[62] Mr. Smiles, in his interesting “Lives of the Engineers” (i.) states that, in 1790, Lord Stanhope had proposed a mode of propelling vessels by steam, and had been in communication with Mr. Rennie on this subject, who, on the 26th April of that year, sent his Lordship such information as he could obtain about Boulton and Watt’s improved steam-engine. Lord Stanhope objected to the space occupied by the condensing apparatus, to which Mr. Rennie replied that high pressure could be applied, on which his Lordship constructed a vessel on that plan which obtained a speed of 3 miles an hour (vol. ii. p. 237).
[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.