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idea is discarded. And it is doubtful whether Branca was the real inventor, as his book is avowedly “a collection of machines invented by others; and

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this mode of moving a wheel by steam is probably, therefore, an idea of which he is the mere illustrator.” He was, however, a man of taste, as well as a person of ingenuity."

From the period now arrived at, up to the middle of the seventeenth century, history has no record as to the advances of the improvement of the steam-engine. All the contrivances hitherto published seem to have been more the result of closet study than every-day practice; more to be looked upon as the playthings of our philosophers than the purposed inventions of the practical mechanic. To this, however, De Garay's steam-boat propeller may perhaps be an exception; nevertheless it can be classed only as an experiment-questionless a successful one---and the barren results of which, in all probability, arose from some inherent defect in its principle or construction. At all events, up to the interesting period we now approach, no useful application of steam to the practical purposes of everyday life had yet been successfully introduced.

In 1663 the Marquis of Worcester, a nobleman who had undergone many changes of fortune in the civil wars of England, published a work entitled “A Century of the Names and Scantlings of such Inventions as at present I can call to mind to have tried and perfected, which,

my

former notes being lost, I have, at the instance of a powerful friend, endeavoured now, in the year 1655, to set down in such a way as may sufficiently instruct me to put any of them in practice.” Amongst the numerous devices which he enumerates, the following is the one which is closely connected with our present subject: “ An admirable and most forcible way to drive up water by fire; not drawing or sucking it upward, for that must be, as one philosopher calls it, infra sphærum activitatis, which is not at such a distance: but this way hath no bounds if the vessel be strong enough; for I have taken a piece of a whole cannon whereof the end was burst, and filled it three-quarters full, stopping and screwing up the open end, as also the touch-hole, and making a constant fire under it.

Within twentyfour hours it burst, and made a great crack; so that having a way to make my vessels so that they are strengthened by the force within them,

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and one to fill after the other, I have seen the water run like a constant fountain-stream forty feet high. One vessel of water rarefied by fire driveth up forty of cold water; and a man that tends the work has but to turn two cocks, that one vessel of water being consumed, another begins to force and refill with cold water, and so successively; the fire being tended and kept constant, which the selfsame person may likewise abundantly perform in the interim between the necessity of turning the said cocks.” The connection between this, the sixty-eighth proposition of the Marquis, and the two following, being the ninety-eighth and one hundredth, has been pretty conclusively established by a writer in the second volume of the Glasgow Mechanic's Magazine : “An engine so contrived,” says the proposition, “ that working the primum mobile forward or backward, upward. or downward, circularly or cornerwise, to and fro, straight upward or downright, yet the pretended operation continueth and advanceth, none of the motions above mentioned hindering, much less stopping, the other; but unanimously and with harmony agreeing, they all augment and contribute strength unto the intended work and operation; and therefore do I call this a semi-omnipotent engine, and do intend that a model thereof be buried with me. The next proposition is as follows: "How to make one pound weight to raise an hundred as high as one pound falleth, and yet the hundred pounds descending doth what nothing less than one hundred pounds can effect.”

“Upon so potent a help as these two last-mentioned inventions, a waterwork is, by many years' experience and labour, so advantageously by me contrived, that a child's force bringeth up a hundred feet high an incredible quantity of water, even two feet diameter, so naturally, that the work will not be heard into the next room; and with so great care and geometrical symmetry, though it work day and night from one end of the year to the other, it will not require forty shillings reparation to the whole engine, nor hinder one day's work; and I may call it the most stupendous work in the whole world : and not only with little charge to drain all sorts of mines, and furnish cities with water, though never so high-seated, as well as to keep them sweet, running through several streets, and so performing the work of scavengers, as well as furnishing the inhabitants with sufficient water for their private occasions,—but likewise supplying rivers with sufficient to maintain and make them portable from town to town, and for the bettering of lands all the way

it runs.

With

many more advantages, and yet greater effects of profit, admiration, and consequence; so that deservedly I deem this invention to crown my labours, to re rd my expenses, and make my thoughts acquiesce in the way of further inventions." * « The primum mobile," says a writer of authority on the steam-engine, " is here evidently the force of steam, that, flow in whatever direction it may, is still capable of exerting the same mechanical power; and the movements, however numerous, can be made not to interfere with each other. The fall of a pound weight raising a hundred pounds weight clearly refers to a mechanism like a piston: one weighing a pound attached to a lever would raise one hundred pounds as high as one pound falleth; and were the weight of water to fall on a water-wheel, for instance, as is now often practised, it would raise a quantity very nearly equal to its own weight, and to the same height from which it fell. A child's force, too, would be sufficient to turn a cock even of a large engine; and the small noise made by this description of machinery, and its working day and night without intermission or im

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pairing its power, are circumstances in the use of the machine now familiar to every person. It would be difficult to give a clearer description of the action of a steam-engine in general terms, without a special explanation of its minutiæ and principles. In this case, however, it obviously was the intention of Lord Worcester to conceal both.” No drawing of this form of engine is extant, by which a notion of its arrangements can be obtained. Diagrams have, however, been given by various writers, detailing arrangements by which the effects as noticed by the marquis could be obtained. These, of course, are perfectly hypothetical; nevertheless, as a matter of some curiosity, we append a diagram illustrative of an arrangement proposed by Mr. Stuart, in his work Historical and Descriptive Anecdotes of the Steam-engine, a work abounding in interesting matter (in fig. 7). Steam is

supplied to the receivers a b by a steam-pipe proceeding from a boiler; the steam is admitted alternately to the receivers ab by means of a cock placed at e. The receivers are connected with the deduction pipe i by

a pipe m, containing valves opening 6

outwards from each receiver; another pipe nu connects the cistern with the receivers; by means of the cock at n the communication between the cistern and each receiver may be interrupted at pleasure. The steam from the boiler passes into the receiver a,

previously filled with water; pressing 6

on its surface, it forces the water through the pipe m up the pipe i, which conveys it to its destination. After the water is expelled from the

receiver a, the cock e is turned, which fig. 7.

admits the steam into the receiver b;

simultaneously the cock n is turned, which admits water from the cistern into a; the steam pressing on the surface of the water in b, forces it up the pipe i; on the whole of the water being expelled, the cock e is turned, shutting off the communication with the boiler from b, but opening it to a. Unless, however, the boiler from which steam is supplied is provided with means for filling it with water at intervals, to compensate for that evaporated during the process of working, it is evident that the continuity of action of the engine would be interrupted. An eminent authority therefore considers that there could not have been in this kind of engine "any feed-pump: in the absence of that instrument, two boilers must have been indispensable to make the action of the engine continuous.' It will be interesting to trace briefly the evidence which has been collected in support of the opinion that the Marquis of Worcester had actually carried his engine into practical effect, this being with many a debatable point. In looking over the preposition of his celebrated work, it will be observed that he speaks of having “ seen the water” raised; of having a way to make his vessels.” Again, although the marquis's veracity may be doubted in these incidental notices, it is worthy of note that a manuscript

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found after his death bore this heading: “The Lord Marquis of Worcester's ejaculatory and extemporary thanksgiving prayer, when first with his corporeal eye he did see finished a perfect trial of his water-commanding engine, delightful and useful to whomsoever hath in recommendation either knowledge, profit, or pleasure." Other corroborative evidence might be given, but it is deemed sufficient to append a very conclusive statement of one who was neither influenced by prejudice or interest. The evidence to which we allude is that given by Cosmo de Medicis, Grand Duke of Tuscany, who visited England about the period of the invention, and whose movements during his travels were duly recorded by his secretary. Under date May 28th, 1699, is the following entry: “ His Highness, that he might not lose the day uselessly, went again after dinner to the other side of the city, extending his excursion as far as Vauxhall, beyond the palace of the Archbishop of Canterbury, to see an hydraulic machine invented by my Lord Somerset, Marquis of Worcester. It raises water more than forty geometrical feet by the power of one man only; and in a very

short space of time will draw up four vessels of water through a tube or channel not more than a span in width, on which account it is considered to be of greater service to the public than the other machine at Somerset House." " This, therefore, is superior in its operations to another machine by a different machanic, and applied to the same purpose.The following is the entry in the Duke's journal of the other machine to which allusion was made in the first entry: “ His Highness went to see an hydraulic machine raised upon a wooden tower in the neighbourhood of Somerset House, which is used for conveying the water of the river to the greatest part of the city. It is put in motion by two horses, which are continually going round; it not being possible that it should receive its movements from the current of the river, as in many other places where the rivers never vary in their course." Nothing can be more satisfactory,” says Mr. Stuart, “than this last notice. The water in the hydraulic machine at Vauxhall, by the most easy inference, was not elevated by a water-w.eel, otherwise the Grand Duke would not have omitted so striking a deviation from that at Somerset House. The effect was equal to that of another worked by two horses; and a tyro in mechanics would at first sight say, that no combination of machinery could accomplish that work by one man which it required the power of twelve men to do in another. From all the circumstances, therefore, it appears to us clear, that this great effect was produced by some sort of a steam-engine: the very identical 'most stupendous water-commanding engine;' the semi-omnipotent engine;' the admirable and most forcible way to drive up water by fire.""

The introduction of this, the first “feasible” scheme for producing useful effects by the power of steam, may be said to be the turning-point in the history of the steam-engine. From this time the march of progressive improvement was rapid and uninterrupted ; invention followed invention, improvement succeeded improvement, until the steam-engine arrived at its present potent condition.* From this stage of our labours we shall cease

* Sir Samuel Morland in 1683 submitted to Louis XIV. of France a plan for raising water by the aid of steam. The following notice is extracted from a Ms. in the British Museum. “ The principles of the new power of fire invented by the Chevalier Morland in the year 1682, and presented to his most Christian Majesty 1683.- Water being evaporated by the power of fire, the vapour shortly acquires a greater space (near 2000 times)

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to record the crude and visionary speculations of the philosopher or enthusiast; but have the more useful and pleasant task of describing the practical results of the application of the labours and ingenuity of our engineers and mechanics.

It is supposed by some engineers, that the method of raising water by steam, on the principle of atmospheric pressure (or the vacuum), was not unknown to the Marquis of Worcester ; and that it is not improbable but that in the engine mentioned by the Grand Duke of Tuscany this agency was taken advantage of. This is, of course, mere conjecture ; but in an invention next in chronological order, now to be noticed, atınospheric pressure, or the formation of a vacuum, was a distinguished feature. The engine to which we allude is that so well known as Savery's.” The period of the introduction of this engine may be looked upon as the commencement of the practical era ; the very mode in which the inventor ushered it into the world, and presented its claims to consideration, proved this. In place of clothing his description in the studied mysticism of words, which up to this period had been the endeavour of all those who had preceded Savery in describing inventions in connexion with the subject, he, on the contrary, fully explained the principles of its action and the details of its arrangements; and instead of giving exaggerated statements of its power and economy, he practically detailed the reasons why he believed it to be a cheaper method of raising water from mines than any other plan then in operation ; and earnestly invited parties interested to inspect the machine in operation, and form their own opinion as to its working value. Very little is unfortunately known of this ingenious man. From his title of Captain it has been conjectured that he was a seafaring man; probably this arose from his having been the inventor of an improved method of moving ships in a calm. It is doubtful whether he was or not; indeed, the latter is likely the case, as, in one of his papers describing an invention of his, he remarks: “I believe it may be made useful to ships ; but I dare not meddle with that matter, and leave it to the judgment of those who are the best judges of maritime affairs." This does not read like the statement of one who was a practical seaman. Mr. Stuart conjectures, with greater probability, that he was the director or proprietor of a mine, and as such was known by the title which is even now appropriated to the same officer.

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than the water occupied before; and were it to be always confined, would burst a piece of cannon; but being well regulated according to the laws of gravity, and reduced by science to measure, to the weights and balance, then it carries its burden peaceably (like good horses), and thus becomes of great use to mankind; particularly for the elevation of water, according to the following table, which marks the number of pounds which may be raised 1800 times per hour, by cylinders half full of water, as well as the different diameters and depths of the said cylinders.” Although no account is obtainable of the contrivance for raising water said to have been submitted by Morland to the King of France, the above extract is sufficient evidence of his being acquainted with the power of steam, and as to the value of its application to useful purposes. The table referred to in the above notice need not be given here; it bears with it the evidence of much care having been taken in the experiments necessary to obtain the given results, which may be said to possess considerable accuracy. It is but just, however, to notice that it is quite an open question whether Morland ever really submitted any plan for raising water by steam, as has been said. One historian of authority states that there is no distinct evidence as to his having done so; and in his book published in 1685, describing all sorts of machines for raising water, he makes not the slightest mention of his being in possession of any such plan.

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