An even closer approach to practical success was made in Scotland by James Symington, who in 1788, in association with two other Scotchmen, Miller and Taylor, constructed a boat consisting of two hulls, with a paddle-wheel between them worked by a steam-engine. This boat worked so well that in 1801, Lord Dundas engaged Symington to build a smaller boat to be used for towing on the Caledonian Canal. This boat, called the _Charlotte Dundas_, completed in 1802, is said to have been capable of towing a vessel of one hundred and forty tons "nearly four miles an hour." But in doing this the resulting "wash" so threatened the banks of the canal that the vessel was laid up and finally rotted and fell to pieces. By many impartial judges this boat is considered the first practical steamboat, and its failure to establish its claim due to the force of circumstances rather than to any inherent defects. Symington was too poor to pursue his work independently, and was deterred by the attitude of James Watt, who "predicted the failure of his engine, and threatened him with legal penalties if it succeeded." And when at last he received an order for eight smaller vessels from the Duke of Bridgewater, his patron died before the details of the agreement had been completed. So that while he failed in accomplishing what was done by Fulton a few years later, it is certain that, as Woodcraft says, "He combined for the first time those improvements which constitute the present system of steam navigation." Some of Symington's engines have been preserved, and one of them is now in the Patent Office Museum in London. Since the beginning of practical steam navigation this engine has been tested several times, the result showing that Woodcraft's estimate is not overdrawn. While Symington was thus perfecting a paddle-boat, an American, Col. John Stevens of Hoboken, New Jersey, was on the verge of accomplishing the same end with a screw-propeller boat--a form of steamship that did not come into use until some forty years later. [Illustration: THE STEAMSHIPS "CHARLOTTE DUNDAS" AND "CLERMONT." The "Charlotte Dundas" (lower figure) was built in 1801 by A. Hart at Grangemouth, Scotland, and engined by William Symington, for service on the Forth and Clyde Canal. Its length was 56 feet; beam 18 feet; depth 8 feet. The boat was a practical success, but its use was discontinued because of the damage done to the banks of the Canal by the wash of the paddles. The upper left-hand figure is a picture of Fulton's "Clermont." The diagram at the right represents the "Clermont's" paddle wheels and the mechanism by which they were worked.]