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the engine, and still more of the boiler, Mr. Gurney exhibited admirable ingenuity, and by opponents as well as friends it was allowed that his trials were successful. Before an experiment was made, it was thought the resistance between the wheels and the road would not be sufficient for the propulsion of the carriage up a steep hill, but this he practically disproved by driving the engine on several occasions up Highgate Hill, and afterwards by a journey from London to Bath. The success of the experiments, however, increased the opposition, and one objection after another was raised, but chiefly, it must be confessed, by persons who, however honestly expressing their opinions, were interested in the failure of the invention. The possibility of a boiler explosion was perhaps the only objection indulged in by the public. The quibbles of highway commissioners, and the abuse of stable-boys, were merely a repetition, in a new form, of the objections before made to the railway system. But none of these impediments would have prevented the ultimate introduction of the locomotive upon the turnpike road, had not experiment proved that the cost of working it would have been greater than upon railways, and that competition in the present state of science was useless.

The rapid extension of the railway system, and the comparative safety in travelling it has produced, are little less wonderful than the improvements which have been made in the locomotiveengine. There are now in the United Kingdom about six thousand five hundred miles of railway

in constant work, and in the United States there are ten thousand miles in operation, and nine thousand in progress. Supposing the latter to be complete, which they will be at no distant period, the British and American railways, united as a continuous line, would encompass the earth at the equator.

CHAPTER VIII.

THE STEAMBOAT AND MARINE ENGINE.

WHEN steam was first studied in modern times as a mechanical force, it was with the intention of applying it to the propulsion of vessels. The invention of Blasco de Garay, the Spanish seacaptain, it will be remembered, was to give motion to a vessel, and, although nothing is known of his machinery, paddle-wheels were employed. This idea (whether it was original, or borrowed from some preceding but unknown inventor, we cannot tell) was never lost sight of by any subsequent mechanist. Nor is this strange; for although new discoveries are frequent in other branches of science, practical mechanics consist in the application of known, and frequently the most common agents, to new and beneficial purposes.

Papin, whom we have also mentioned as a steam-engine projector, proposed to apply his design so as to move vessels against wind and tide. The mode in which he designed to accomplish this bears a close resemblance to the arrangement now adopted in steamboats. His contrivance was to place a shaft across the vessel, and at each end to fix a paddle-wheel, motion being given to

the shaft by connection with the engines. Savery, another steam-engine projector, already mentioned, says that his contrivance might be very useful in ships, but that he must leave the application to those who are better acquainted with maritime affairs: strangely enough, however, he took out a patent for a shaft and paddle-wheels, for the propulsion of vessels, which he worked by a capstan. This engine, as he calls it, he tried on the Thames, but its usefulness, as he himself informs us, was denied by Mr. Dummer, the surveyor of the navy, because it was the same sort of contrivance that had been used at Chatham, in the year 1682, for towing government vessels, and had been employed at a loss to the crown. This, as Dr. Muirhead states, was probably the vessel made under the direction of Prince Rupert, having paddle-wheels worked by horses; "and which, on a trial on the Thames, witnessed by Papin, beat the king's barge, manned by sixteen rowers."

These facts-and many others might be added if necessary-prove that three hundred years ago, at least, a shaft and paddle-wheels were fixed in a vessel to propel it against wind and tide. The want of a sufficiently powerful and constant force made this design useless: as the railroad waited for the locomotive, so did the shaft and paddlewheels for the marine engine. We shall, therefore, do little injustice to our subject by passing over all the vain efforts to propel vessels without sails and oars by "new inventions and devices,"

and proceed at once to the examination of the history of the marine engine.

As soon as Mr. Watt had constructed his singleaction steam-engine, the Americans suggested its application to the purposes of navigation, and, as early as the year 1783, an attempt was made by Fitch and Rumsey to propel a vessel by steam. They failed, it is true, but more from the want of suitability in the engine to the purpose for which it was employed, than from deficiency of mechanical skill and perseverance. But their unsuccessful attempt was no discouragement to others: the design may have been for a time suspended, but was not abandoned. In 1791, John Stevens, of Hoboken, commenced the study of the steam-engine and its application to navigation, and to his great honor continued his experiments for a period of sixteen years, occasionally assisted and advised by Livingstone, Roosevelt, and the elder Brunel. After this long and tedious course of investigation, conducted with ingenuity and perseverance, he was not, as he hoped to be, the first to establish a steamboat on an American river. Fulton was a few weeks before him, and during that period obtained from Congress the exclusive right to navigate the Hudson with a steam-vessel a monopoly which ought not to have been granted, and was afterwards properly withdrawn, as being unconstitutional.

The fact that Fulton was the first to navigate an American river with a steam-vessel, is sufficient to draw our attention to the history of his

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