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EXPERIMENTS ON STEAM.

31 he propounds in a theorem, that, by means of heat, water will rise to a height above that of its level.* Water is introduced into a copper globe, (fig. B,) a, by a funnel; and another pipe, i, descends through the fluid to nearly the bottom of the vessel. The globe is placed over a fire; the vapour which is generated in the upper part of the ball, expanding, presses on the surface of the water, and forces it up the pipe i, the stop-cock, atm, preventing the escape of the steam from the funnel.

Cardan, we have observed, had some clear notions of the properties of steam, but many others of the alchymists are familiar with the facts more directly elicited from Decaus's experiments ; indeed, every distillatory process must have forced on their attention the great expansive power of steam ; its return by condensation into water; and that the fluid, thus produced, was equal in bulk to that it possessed before it was converted into vapour. But then a simple statement of a plain matter never was sufficient for their sublime imaginations; some frigorific, ethereal, or ignific”spirit was either to be let loose or bound in chains, or propitiated, before the phenomena could be accounted for or explained. Decaus, therefore, (la première fois que l'on a mis le vaisseau sur le feu) est retournée en eau la seconde fois que la dite vapeur a este enserré dans le vaisseau et qu'il s'est refroidy de luy-mesme.” p. 3. Ibid.

THEORESME. (Fig. 11.) "L'eau montera par aide du feu plus haut que son niveau dont il se peut faire diverses machines i'en donneray icy la démonstration d'une. Soit une balle de cuivre marquée a, bien soudée tout à l'entour, à laquelle il y aura un souspiral marqué m, par où l'on mettra l'ean, et aussi un tuyau mar. qué i, qui sera soude en haut de la balle, et le bout approchera près du fond sans y toucher, après faut emplir la'dite balle d'eau parsle souspiral puis le bien reboucher et le mettre sur le feu, alors la chaleur donnant contre la dite balle fera monter toute l'eau par le tuyau'i.” p. 4. Ibid.

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ingenious though he be in his labour, marks no progression, unless stating appearances as he saw them may, as it ought, be considered to his honour.

The application of this power was not suggested by Decaus to any purpose, beyond that shown in his model. Yet a fire applied, instead of his mirrors, to an arrangement of vessels and pipes, with their cocks, as he describes in his sun's heat machine, (fig. X,) could scarcely have left any thing to be wished for, as a simple, efficient, and inge. nious substitute for manual labour in raising water.

The scheme of Branca, an Italian architect and engineer, in 1629, exhibits a different mode of applying the agency of steam ; here its impulsion on a wheel produces a rotary motion. The water is heated in an elipile, a, by a fire placed beneath it, c, and the steam, issuing from its orifice on the vanes of a wheel,0, causes it to revolve; and its continuous motion is communicated to other wheels, moving stampers suspended over mortars.* A

*“Da qual si voglia figura si puo cauare principij et fondamenti buoni per seruirsene all occasione, la figura è fatta per pestare le materie per far le poluere ma con un mo tore meraviglioso che non è altro che una testa di metalla con il suo busto segnato per, a, empito d'acqua per il foro, C, posta sopra carboni accesi nel foculare, i, che non possa esa lare in altro luoco che nella bocco in sito, o, farà fiato cosi violento che voltando la ruota, n, et il suo rocchetto, m, dara nella ruota dentata, x, e con il suo rocchetto, u, muouela rota, ?, quale con il rocchetto, e, muoue la ruota, r, con il cilindro impernato per alzare li doi pistoni, s, s, inserti nelli sostegni, w, t, quale alzandozi a vicenda sopra le vasa di metalla, v, și pestarà la poluere et altre materie che bisognaranno, &c."

LE MACHINE. Volume nuovo et di molto artificio da fare effetti maravigliosi si tanto spiritali quanto di animale opera tione arichito di bellissime figure conle dichiarationi a ciascuna di esse in lingua volgare et latina. Del Sig. Giovanni Branca, cittadino Romano, Ingegniero and Architetto della Sta. Casa di Loretto. In Roma MDCXXIX.

p. 25.

DREBBEL.

33 slight inspection of Branca's diagram will be sufficient to convince us, that his series of wheels, and the stampers and the mortars, are introduced more to show how steam might be applied, than that it ever was so. His book besides is avowedly a collection of machines invented by others; and this mode of moving a wheel hy steam, is probably, therefore, an idea of which he is the mere illustrator. He gives another figure in his volume, in which he shows the smoke, rising through a pipe from a small smith's hearth, moving a wheel, which communicates motion by other wheels to cylinders, for flattening iron bars. This by the smoke, and that by the steam, may therefore be equally efficient; and both, probably, have similar pretensions to being considered as ever having been applied in practice. The picturesque arrangement of his apparatus will be readily admitted as a proof of the position, at least, that Branca was a man of taste, as well as a person of ingenuity.

The year following that of the publication of Branca's book, the ingenious Cornelius Drebbel, who has left so great a reputation for ingenuity, and so few of whose works remain on which it was founded, put in practice the device which has been described as producing the sounds in the Egyptian idol.

"A musical instrument which, being set in the sunshine, would of itself render a soft and pleasant harmony, but being removed into the shade would presently become silent : the reason of it was this, the warmth of the sun working upon some moisture within it, and rarefying the inward air onto so great an extension, that it must needs seek a vent or orifice, did thereby give several motions unto the instrument,'

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air."

Bishop Wilkins,* "a person of rare gifts, a noted theologist and preacher, a curious critic in several

* Dr. John Wilkins, bishop of Chester, married Robinna, the widow of Peter French, and sister to Oliver Cromwell. Archbishop Tillotson married his daughter in law. He was as Wood's character, given in the text, one of the most re. markable men of his time. One of his most curious productions was a discourse tending to prove “ that it is probable there may be another habitable world in the moon.” This produced much merriment for the wits; among others, the celebrated Duchess of Newcastle objected to the doctor's proposition, “ that it is possible for some of our posterity to find out a conveyance to this other world,” and suggested the want of baiting places on the way; the Doctor's reply was an expression of surprise, “ that this objection should be made by a lady who had been all her life building castles in the

“ If it be inquired,” says the bishop," what means there may be for our ascending beyond the sphere of the earth's magnetical vapour, I answer. 1. It is not, perhaps, impossible that a man may be able to fly by the application of wings to his own body; as angels are pictured, and as Mercury and Dædalus are fained; and as hath been attempted by divers, particularly by a Turk in Constantinople, as Busbequius relates. 2. If there be such a great ruck in Madagascar, as Marcus Polus the Venetian mentions, the feathers in whose wings are twelve feet long, which can scoope up a horse and his rider, or an elephant, as onr kites doe a mouse; why then it is but teaching one of these to carry a man, and he may ride up thither as Ganymede does upon an eagle. 3. Or if neither of these ways will serve, yet I do seriously, and upon good grounds, affirm it possible, to make a flying chariot, in which a man may sit and give such a motion unto it as shall convey him through the air; and this, perhaps, might be made large enough to carry, divers men at the same time, together with food for their viaticum, and commodities for traffique. It is not the bigness of any thing in this kind that can hinder its motion, if the motive faculty be answerable thereunto. We see a great ship swim as well as a small cork; and an eagle flies in the air as well as a little gnat. This engine may be contrived from the same principle by which Archytas made a wooden dove, and Regio Montanus'a wooden eagle. I conceive it were no difficult matter, if a man had leisure, to show more particularly the means of composing it. The perfecting of such an invention would be of such excellent use, that it were enough to make a man, but the age also wherein he lives; for, besides the strange discoveries that it might oeca

WILKINS.

35 matters, and an excellent mathematician and experimentalist, and one as well seen in mechanism and new philosophy, of which he was as great a promoter, as any man of his time,” in 1648, mentioning Cardan's idea,* describes another use sion in this other world, it would also be of inconceivable advantage for travelling above any other conveyance that is now in use; so that, notwithstanding all those seeming im. possibilities, 'tis likely enough that there may be a means invented of journeying to the moon ; and how happy shall they be that are first successful in the attempt.”

Might not a high pressure' be applied with advantage to move wings as large as those of the 'rucks,' or the chariot.' The engineer might, probably, find a corner that would do for a coal-station, near some of the castles.'”

* In addition to the uses of the smoke-jack enumerated by Car. dan, the bishop mentions“ chiming of bells, or other musical devices; and there cannot be any more pleasant contrivance for continual and cheap music : it may be useful also for the reeling of yarn, the rocking a cradle, with divers like domestic occa

Math. Mag. p. 86. In the books on heating buildings, the first application of steam to this use is ascribed to a Colonel William Cook in 1745. But in a posthumous work of Sir Hugh Platte, published in 1660, it is suggested as a mode of heating a conservatory: "and for the keeping of any flowers or plants abroad, as also of those seeds thus sowed within doors, or any other pots of flowers or dwarf-trees in a temperate heat, with small charge you may perform the same, ly hanging a cover of tin, or other metall, over the vessel wherein you boil your beef, or drive your buck, which having a pipe in the top, and being made in the fashion of a funnel, may be conveyed into what place of your orchard or garden you shall think meet; which room, if it were so made as that at your pleasure it may become either close or open, you may keep it in the nature of a stove in the night season, or in any other cold weather, and in the summer time you may use the benefit of the sunbeams to comfort and cherish your plants and seeds; and this way, if I be not deceived, you may have both oranges, lemons, pomegranates, yea, peradventure, coloquintida, and pepper trees, and such like. The sides of this room, if you think good, may be plastered, and the top thereof may be covered with some strained canvas to take away at your pleasure. Quere if it be the best to let the pipe of lead to breathe out at the end onely, or else at divers small vents

sions."

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