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principles Mr. Watt has applied to the fire engine before you " knew Mr. Watt's engine?” And upon oath he answered, "My situation in life leads me to see a vast many mechanical “ contriyances, and my inclination leads me to look into “ them. I take it to be the most useful engine that has ever “ been brought forward by the mind of man; I have con“ sidered it attentively; I do declare I never saw the principles laid down in Mr. Watt's specification either applied to the engine previous to his taking it up, nor ever read of any such thing whatever.

If it be true,-although of this we have no proof beyond Hornblower's assertion,—that Mr. More had inspected Mr. Humphry Gainsborough's “ working-model” to which his “ discoveries” were “applied,” this only makes his evidence in favour of the entire novelty as well as originality of Mr. Watt's steam-engine the more conclusive. Mr. Humphry

Gainsborough's opinion of the value of his own machine, as compared with that of Watt, appears, no doubt, to have been tolerably good; for “Suppose," writes Mr. Boulton to Mr. Watt in 1775, “ another ingenious man starts up with “ another new discovery that should prove to be seven times “ better than the common engine, whilst ours is only three

times, what then becomes of all the fabric we have raised, “ and of the visionary profits? And let me tell you that “ there is great probability of it, for there is a very ingenious “ man at Henley-upon-Thames, who asserts that he hath “ made such a discovery.” The person here alluded to,who would have been very ingenious indeed if the ratio of seven to three in favour of his steam-engine against that of Watt had only proved to be true,—was no doubt Gainsborough ;-as in a subsequent letter, believed to have been written in 1776, Mr. Boulton talks of " Tubal-Cains, or Watts, “ or Dr. Fausts, or Gainsboroughs, arising with serpents like “ Moses', that devour all others."

Humphry Gainsborough is stated to have died in 1776, under a “deep and melancholy impression on his mind” of having failed; but very possibly retaining that conceit of the superiority of his own “ discoveries” which seems to some extent to be habitual with projectors, but especially with unsuccessful ones. Those who, like Newton or Watt, do really make great scientific discoveries which truly and widely enlighten and benefit mankind, and deservedly command the admiration of the world, are usually less sanguine, and always, we venture to believe, more modest. Stuart, in his History of the Steam-Engine, calls Hornblower's story, quoted above,

“extraordinary and disingenuous statement;" and the friends of Mr. Fulcher, whose publication is a posthumous one, must regret that, after the interval of more than half a century, he should have given renewed currency to so groundless a tale.

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CHAPTER IX.

HISTORY OF THE STEAM-ENGINE BEFORE THE TIME OF WATT ÆOLIPILES

-ANTHEMIUS - GERBERT PORTA- RIVAULT SOLOMON DE CAUS MARQUIS OF WORCESTER HIS CENTURY OF INVENTIONS QUESTION WHETHER HE EXECUTED HIS APPARATUS HIS ACT OF PARLIAMENT

- BEAUFORT MSS. — ROLLOCK'S 'PANEGYRIC - TRAVELS OF COSMO DE MEDICIS.

As we are now arrived at that important epoch of Mr. Watt's life when he made the first, the greatest, and the most prolific of all his inventions connected with the steam-engine, it is necessary that we should give some explanation of the state in which he found that machine, as then employed in imperfectly draining some collieries and mines in Great Britain, although not otherwise made available in either this or any other country. Without a brief historical sketch such as this renders necessary, many of our readers might find it difficult to follow the steps by which Mr. Watt ascended in his successive inventions, to understand their importance, or to appreciate their beauty; and we venture to believe that it is possible to communicate all that is on the present occasion needful to be known on this part of our subject, without perplexing our narrative by details either very numerous, or at all obscure.

The earliest instance of a machine in which steam was deliberately used to generate motion, is, it seems to be generally admitted, the Æolipile,- Æoli-pila, or ball of Æolus,—such as is delineated and described by Hero of Alexandria, in his Pneumatica, or Spiritalia,* about 120 B.C. This æolipile was a hollow ball of metal, moveable on external axes working in sockets, and fitted with one or more tubes issuing from it horizontally, closed at their ends, but with an opening in

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A curious treatise, which, along in the ‘Mathematici Veteres,' Gr. et with his other works, is to be found Lat., Par. 1693, fol.

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their sides. This ball being partially filled with water, and placed over a fire, the re-action of the steam, rushing with violence from those openings, caused it to revolve with more or less rapidity according to the force of steam employed. The machine has been constructed of several forms, and has often served purposes of ingenious amusement. In point of practical utility, it is recommended by Branca, in his work entitled “Le Machine,' published at Rome in 1629, to be used to produce a rotatory motion, by acting on the pinions of a wheel. It has also been employed instead of bellows, directing a strong current of steam on the fire, in place of a blast of air. Sir Hugh Plat, at p. 23 of his ‘Jewel House of * Art and Nature,' (printed at London in 1653), gives a particular description of one which he calls “A round ball of

copper or Latten, that will blow the fire very strongly, “onely by the attenuation of water into air; which device " may also serve to perfume with ;” and he annexes a woodcut of it.

But the most singular details as to an instrument of this sort with which we have met, are given in the following passage, taken from Plot's Staffordshire :-“Yet there are many “ old customs in use within memory, of whose originals I “ could find no tolerable account, that possibly might com

mence as high as these times; such as the service due from “ the Lord of Essington in this county [Stafford] to the Lord “ of Hilton, about a mile distant, viz. that the Lord of the

manor of Essington shall bring a goose every New-year’s

day, and drive it round the fire in the hall at Hilton, at “ least three times, (which he is bound to doe as mean lord), “ whil'st Jack of Hilton is blowing the fire. Now, Jack of

Hilton is a little hollow image of brass of about 12 inches

high, kneeling upon his left knee, and holding his right “ hand upon his head, *** having a little hole in the place “ of the mouth, about the bigness of a great pin's head, and “ another in the back about şof an inch diameter, at which “ last hole it is fill’d with water, it holding about 4 pints “ and \, which, when set to a strong fire, evaporates after " the same manner as in an æolipile, and vents it self at the

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“ smaller hole at the mouth in a constant blast, blowing the “ fire so strongly that it is very audible, and makes a sensible “ impression in that part of the fire where the blast lights, as I found by experience, May the 26th, 1680.” *

” A story is told by Agathias, in his history of Justinian, of a trick played by Anthemius, the famous architect of the church-now the mosque-of St. Sophia at Constantinople, which, amidst all the vagueness and probably ignorance of the historian, seems to indicate some knowledge, on the part of its contriver, of the forcible effects of steam. Anthemius and Zeno the rhetorician occupied contiguous houses; and in a dispute about their walls or windows, the learning of the mathematician was defeated by the eloquence of the orator. In revenge, Anthemius betook himself to the practice of such arts of annoyance as his knowledge of science could suggest; and among other devices, more ingenious than hurtful, by which he sought to disturb the quiet of his neighbour,

one thus recorded by Gibbon:-“In a lower room, “ Anthemius arranged several vessels or cauldrons of water, “ each of them covered by the wide bottom of a leathern tube, “ which rose to a narrow top, and was artificially conveyed “ among the joists and rafters of the adjacent building. A “ fire was kindled beneath the cauldron; the steam of the “ boiling water ascended through the tubes; the house was “ shaken by the efforts of imprisoned air, and its trembling “ inhabitants might wonder that the city was unconscious of “ the earthquake which they had felt !” +

William of Malmesbury describes as being preserved in the Cathedral of Rheims, among other proofs of the mechanical skill of Gerbert, (afterwards Pope Sylvester II., who died A.D. 1003), a hydraulic organ, blown “ by the violence of boiling 6 water.” I

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Natural History of Staffordshire, + Decline and Fall of the Roman " by Robert Plot, LL.D.,' p. 433, edit

. · Empire,' ch. xl. Oxford, 1686. At plate xxxiii. of that Willielm. Malmesbur, de gestis work there an engraved likeness Regum Anglorum,' Lib. ii.; in of Jack, to which we refer those of Rer. Anglic. Script. ed. Lond. 1596, our readers who are curious in such fol. 36, verso. matters,

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