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CHAPTER VI.

STEAM-NAVIGATION AND THE MARINE ENGINE.

Under the present division of our treatise we purpose giving a few historical notes as to the introduction of the steam-engine for the purposes

of navigation, preliminary to the illustrations and descriptions of the modern “ marine engine.” From the limited space now at our disposal, we shall be prevented from going so deeply into the historical details as might by some be considered necessary; but we shall nevertheless endeavour to notice the most important of these.

For many years previous to the application of the steam-engine to the propelling of boats, it had been a favourite object with mechanics, the substitution of sundry mechanical contrivances for sails. The most noticeable of these was the revolving wheel with float-boards on its periphery, which acted, on being immersed in the water, so as to move the boat forward : this, modified somewhat in its arrangements and construction, is identical in principle with the “paddle-wheel” of the modern steam-boat. The various contrivances introduced for boat-propulsion were actuated either by manual labour or that of horses, through the intervention of simple mechanical arrangements. The earliest notice we have of an attempt to substitute the power of steam for these methods of working is that of Blasco de Garay, to whose invention we have already alluded in the first chapter. Captain Savery, in the Miner's Friend, alluded to the capability of steam as a power for moving steam-boats; but it does not appear that he entered further into the matter than making a mere suggestion. Denis Papin, during his residence in England, is said to have constructed a model by which a steam-piston moving in a cylinder gave motion to the axle of the paddle-wheels; a rack was placed on the piston-rod, working into a pinion fastened on the axle of the revolving paddles. He employed two or three steam-cylinders ; and when the piston of the one was ascending, that of the other was working downwards; and as they would give contrary motions, one was detached while the other was in action ; and by this means the motion could be made continuous and tolerably regular.

In 1737 Jonathan Hall published" a description and draught of a newinvented machine for carrying vessels or ships out of or into any harbour, port, or river, against wind or tide, or in a calm.” In this steam-boat the engine used was an atmospheric one, rotatory motion being obtained by a continuous arrangement of pulleys and cords or bands. We give in fig. 161 a diagram illustrative of the general appearance of this boat. From the imperfect mechanical arrangements, and the defects of the atmospheric as a rotative engine, this attempt at steam-boat propulsion was soon abandoned, if indeed it ever went beyond a mere speculation on paper.

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Passing over various unsuccessful attempts made in America by Fitch and Ramsey, in 1785-1793; the Earl of Stanhope in England, in 1795 ; and of the Chancellor Livingstone and the celebrated Brunel on the Hudson in America, in 1797,—we proceed to notice the first successful steamengine. We must, however, go back for a few years prior to the lastmentioned date. In 1787, Mr. Patrick Miller, of Dalswinton, a gentleman who devoted much of his time to experiments in the improvement of artil

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lery and naval architecture, published a description, with drawings, of a “triple vessel moved with wheels.” Convinced that, to give his invention every fair chance, it was necessary to employ some force greater than that of manual labour, he threw out the suggestion of employing the steamengine for the purpose of moving the wheels; the force of steam, amidst other means proposed, presented itself, however, to his mind“ the most potent, the most certain, and the most manageable.” “In Miller's family," says his son, in the narrative published in the Edinburgh Philosophical Journal in 1824," there was at this time, as tutor to his youngest children, Mr. James Taylor, who had bestowed much attention on the steam-engine, and who was in the custom of assisting Miller in his experiments on naval architecture and the sailing of boats. One day, in the very heat of a keen and breathless contest in which they were engaged with a boat on the Leith establishment, this individual called out to his patron, that they only wanted the assistance of a steam-engine to beat their opponents ;' for the power of the wheels did not move the boat faster than five miles an hour. This was not lost on Miller, and it led to many discussions on the subject; and it was under very confident belief in its success that the allusion was made to it in the book already mentioned. In making his first experiments, Miller deemed it advisable in every point of view to begin upon a small scale, yet a scale quite sufficient to deter

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mine the problem which it was his object to solve. He had constructed a very

handsome double vessel with wheels, to be used as a pleasure-boat on his lake at Dalswinton; and in this little vessel he resolved to try the application of steam.” To aid him in the fitting-up of the steam-engine, he secured the services of an engineer to whom he was introduced by Taylor, one whose name will be handed down to posterity as the engineer to whom practical steam-navigation is mainly indebted for its introduction William Symington. It was to this latter individual, an engineer of great practical attainments, that the task of fitting-up the steam-engine was intrusted, In the autumn of the same year in which he was employed, the steam-engine, having brass cylinders of four inches diameter, was placed on board the little pleasure-boat. “Nothing,” says Mr. Miller in his narrative, “ could be more gratifying or complete than the success of this first trial ; and while for several weeks it continued to delight Miller and his numerous visitors, it afforded him the fullest assurance of the justness of his own anticipation of the possibility of applying to the propulsion of his vessels the unlimitable power of steam. On the approach of winter, the apparatus was removed from the boat, and placed as a sort of trophy in his library at Dalswinton, and is still preserved by his family, as a monument of the earliest instance of actual navigation by steam in Great Britain. In the succeeding year, a larger boat, sixty feet long, was tried on the Forth and Clyde Canal ; the engines and machinery were constructed at the Carron Iron Works, near Falkirk ; and in December 1789,

in the presence of a vast number of spectators, the machinery was put in motion." This second trial promised to be every way as prosperous as the first. It happened unluckily, however, that the revolving paddles had not been made of sufficient strength; and when they were brought into full action, several of the float-boards were carried

away,

vexatious stop was for that day put to the voyage. The damage was repaired, and on the 25th December the steam-boat was again put in motion, and carried along the canal at the rate of seven miles an hour, without

any

untoward accident; although it appeared evident that the weight of the engine was an over-burden for the vessel (her planking being only three-quarters of an inch thick), and that under such a strain it would have been imprudent to venture to sea. The experiment, however, was again repeated on the two following days; and having thus satisfied himself (Miller) of the practicability of his scheme, he gave orders for unshipping the apparatus, and laying it up in the storehouses of the Carron Works.” In consequence, as it

appears from the statements in the narrative by his son, Miller was led to abandon further experiments with the view of introducing the steamboat more extensively, partly from the large expenses which the first trial had cost him, and partly from his attention becoming much directed to agricultural pursuits. În 1801, Symington, patronised by Lord Dundas of Kerse, started a steam-boat on the Forth and Clyde Canal, for the purpose of towing boats. The following is Mr. Symington's own narrative: “Mr. Miller being very much engaged in improving his estate in Dumfriesshire, and I also employed in constructing large machinery for the leadmines at Wanlockhead, the idea of carrying the experiments at that time any further was entirely given up, till meeting with the late Thomas Lord Dundas of Kerse, who wished that I should construct a steam-boat for dragging vessels on the Forth and Clyde Canal instead of horses.

and a very

Agreeably to his lordship's request, a series of experiments, which cost nearly three thousand pounds, were set on foot in 1801, and ending in 1802, upon a larger scale (than those on Dalswinton Lock) and more improved plan, having a steam-cylinder twenty-two inches diameter and four feet stroke, which proved itself very much adapted for the intended purposes. Having previously made various experiments, in March 1802, on the Forth and Clyde Canal, Lord Dundas and several other gentlemen being on board, the steam-packet took in tow two loaded vessels, each of seventy tons burden, and moved with great ease through the canal a distance of nineteen and a half miles in six hours, although the whole time it blew a strong breeze right a-head of us ; so much so, that no other vessels could move to windward in the canal that day but those we had in tow, which put beyond the possibility of a doubt the utility of the scheme in canals and rivers, and ultimately in open seas. Though in this state of forwardness, it was opposed by some narrow-minded proprietors of the canal, under a very mistaken idea that the undulation of the water, occasioned by the motion of the wheel, would wash and injure its banks. In consequence, it was with great reluctance laid up in a creek of the canal, exposed for years to public view."

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In fig. 161* we give a drawing of Symington's first engine, and in fig. 1616 a drawing of the second and improved design ; for these we are indebted to the courtesy of Mr. Wm. Symington, of London, the son of the inventor. The following is the description of the various parts :

In fig. 161a, a a are the cylinders, b the boiler, c steam-pipe, d d airpump rods, e e connecting chains, ff direction pulleys, gg paddle-wheels, situated and wrought in a trough extending from stem to stern of the boat, and allowing free ingress and egress to the water ; h h ratchet-wheels, for communicating motion to the paddles; ii the water-line.

In fig. 1610, a the cylinder, b the boiler, c steam-pipe, d eduction-pipe, e condenser and air-pump, g hand-gear and pump-rod, h piston and connecting-rod, supported by the friction-wheels; i the rod which communicates motion to the air-pump lever; j crank; k paddle-wheel, situated in a cavity in the centre of the stern of the vessel; il paddle-wheel cavity, open behind and below to the water; m steer-wheel; nn flotation line. This boat was steered by two rudders connected by iron rods, and wrought in the prow by the steer-wheel.

We come now to notice the exertions of another individual who occu

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pies an important place in the history of steam-navigation-Robert Fulton, an American. Passing over various matters connected with this individual, with reference to other inventions of his, we proceed at once to state that, on the occasion of his visit to Paris, he became acquainted with Chancellor Livingstone, then minister from the United States to the court of France; who, it may be recollected, has been mentioned as having been engaged in conducting steam-boat experiments at one period in America, but who had not succeeded. He explained to Fulton what had been done, informed him that on his return to America he intended to resume his experiments, and invited Fulton to turn his attention to the subject. This Fulton did, and instituted a variety of experiments with a view to ascertain the best expedients to be adopted. After many trials, he determined to use the paddle-wheel. In 1803, the first boat constructed by Livingstone and Fulton was completed ; " the wheels and other mechanism acted according to his (Fulton's) expectations, although her speed was not so great as he calculated upon her machinery producing." "So satisfied, however, were they with this preliminary trial, that they wrote to Boulton and Watt, ordering them to make an engine, with modifications adapted for the peculiar purpose for which it was designed ; this engine to be sent to New York, to which place Fulton intended immediately to return. Livingstone, through the influence of his friends in America, obtained the privilege of navigating the waters of the State of New York by steam for twenty years, in which privilege Fulton was also included. Before leaving for New York, Fulton visited Scotland, and waited on Symington, who explained to him very fully the whole details of his plan. Symington, in his narrative, says, “ Fulton politely made himself known, and candidly told me he was lately from North America, and intended to return thither in a few months; but having heard of our steam-boat operations, he could not think of leaving the country without first waiting upon me, in expectation of see

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