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If the Reader is defirous of having this almoft incredible in ftance of popish prieftcraft, and lay-bigottry, further authen ticated, we refer him to Dr. Middleton's Letter from Rome."
For our Author's account of his travels to Naples, Venice, &c. we refer to his book; concerning which we have only to mention this further particular, viz, that if the Writer's English is fometimes a little deficient, (as well as his French, Italian, &c.) it is by no means improved under the hands of the printer: who appears to have made confiderable additions to the defects of his Author.
Obfervations on a Series of Electrical Experiments By Dr. Hoadley, and Mr. Wilfon. 4to. s. 6d. ‹ Payne. A
F fubtile difputations, founded on arbitrary hypothefes, could have given fatisfactory reasons for the phænomena of Nature, the doctrine of the fchoolmen, or the principles of Des Cartes, would have rendered all fedulous enquiries, and accurate experiments, needlefs. But as all hypothefes, how ever plaufible, are banished from the prefent method of phi lofophizing, and nothing admitted as a principle that will not bear the rigid teft of experiment, every, attempt to account for natural phænomena, on other principles, is juftly looked upon as fuppofititious only, and denied a place among the dif coveries of genuine philofophy. 2 2317 From a great variety of optical experiments, Newton was led to conclude, that there is a very fine Fluid, of the fame nature with air, but extremely more fubtle and elaftic, every where difperfed throughout all space; which Fluid he called Ether: That this æther is much rarer within th the denfe bodies of the fun, ftars, planets, and comets, than in the empty celeftial spaces between them; and, in paffing from them to great distances, it perpetually grows denfer and denfer, and thereby causes the gravity of thofe bodies towards one another, and of their parts towards the bodies; every body endeavouring to go from the denfer parts of the æther, towards the varer: That, therefore, the earth is furrounded every where by this æther, to a very great diftance, in confequence of which the air, and all bodies in it, gravitate towards the earth, and towards each other, agreeably to the appearances at the furface of it: That this æther likewife pervades the pores of all bodies, and lies hid in them; and whilft the bodies, with this fluid in them, are undisturbed by any external violence, this fluid, from its claftic nature, conforms itself, as to its degree of denfity, to
it is in. e. gr. It is not fo
the particular make of that body Such are the properties
dente in denfe bodies as in rare
of the æther, according to Sir Ifaac; but as he was not able to prove fatisfactorily the exiftence of this fine fluid, most of his followers have denied it a place among the principles of the Newtonian Philofophy.
But from the experiments of Dr. Hoadley and Mr. Willon, enumerated in the pamphlet before us, it appears, that there is really, in nature, fuch a fluid, which is the cause of all electrical phænomena; that the electrical fluid is not elementary fire, as many have supposed; but that the æther of Sir Ifaac, and that of electricity, is one and the fame fluid.
As it is impoffible to give the fubftance of their experiments, without tranfcribing too much from the pamphlet, we must refer our philofophical Readers to the whole, and content ourfelves with the following extract; in which the Authors have delivered the refult of their feveral experiments. bu Thus have we, fay they, gone through the moft interWefting of the electrical experiments; and from the various appearances they afford, it appears, that the electrical Auid is as univerfal and powerful an agent, at or near the surface of the earth, as that fluid which Sir Ifaac Newton, in his Optics, calls Æther; that it is as fubtle and elaftic in its nature, as the ture, as æther is; and, as æther does, that it pervades the C pores of all bodies whatever, that we are converfant with; <is difperfed thro' whatever vacuum it is in our power to produce by art, and from the natural phænomena of thunder, Fightning, &c. feems to be extended to very great diftances. in the air
250We fhall make no fcruple, therefore, now to affirm, that < thefe two fluids are one and the fame fluid ¿ as it is much more philofophical to do fo, than to fuppofe two fuch fluids, each of them equally capable of producing thefe effects, and equally prefent every where; which would be multiplying ""caufes, where there is no n manner of occafion,
The word electrical, is of too confined a meaning to be a proper epithet for a fluid of fo univerfal an activity, as this is found at laft to be, from the experiments we have been confidering, becaufe it expreffes its power but partially. AoElectricity means no more than the power we give bodies by rubbing them, to attract and repel light bodies that are near them, in the fame manner as amber does when it is rubbed. But this fluid not only makes light bodies, that are a near an electrified body, fly to and from that body, and fo appear to be attracted and repelled: but it heats them, by Hh 2 6 putting
1502 28 qt ejjud muñoids 2325; putting their component particles, and the particles of air. and light within them, into a vibrating motion; and makes them throw out the rays of light, that before lay hid, and part with their fulphureous, and volatile component parti-, cles, which, with the rays of light, on mixing with the air, burst out into parks of real culinary fire, as the chemifts exprefs themselves; nay, more, in paffing through canimals, it occafions convullions, tremors, pain, and death ⚫fometimes; and in paffing violently through leaf-gold, held tight between two pieces of glafs, makes a fufion both of the gold, and of the furface of the glass, fo inftantaneoufly, that no fenfible heat remains in them, and they immediately safter become incorporated, and form an enamel. 079 It is likewife improper to call this fluid, Fire. Air may juft as properly be called found, as this fluid can be called fire. When found is produced, the particles of the air are put into fo regular a motion, as to convey fuch fenfations, by means of the car, as raile the idea of found. But air is hot therefore found. In the fame manner, when a body has all its component particles thrown into fuch agitations in the air by the force and action of this fluid, within it, and without it, that it grows hot, and fhines, and glows, and confumes away in imoke and flame, we fay the body is on fire, or burns, but this fluid is not therefore fire: nor can it, without confounding our ideas, have that name given to have that is it; nor, indeed, can fire be called a Principle, or Element, nciples in the chemifts fenfe of the word, any more than found 19do dora BGENE gopstion dou En Sir Ifaac Newton, at the end of the Principia, in the fecond edition, anno 1713, defcribes this fluid, and its effects, in the following words; and fays, exprefsly, that it is the caufe of the Electricity. but goißen od: bab
o Adjicere jam liceret nonnulla de fpiritu quodam fubtilif"fimo corpora crafla pervadente et in iifdem latente: cujus vi, et actionibus particulæ corporum ad minimas diftanties 660 fel mutuo attrahunt, et contigua facta coherent: et corpora electrica agunt ad diftantias majores tam repellendo quam Aattrahendo corpufcula vicina: et lux emittitur, reflectitur, to refringitur,inflectitur, et corpora calefacit: et fenfatio omnis excitatur, et membra animalium ad voluntatem moventur vibrationibus fcilicet hujus fpiritus per folida nervo* rum capillamenta ab externis fenfuum organis ad cerebrum, "et a cerebro ad mufculos propagatis. Sed hæc paucis expo"ni non poffunt; neque adeft fufficiens copia experimentorum,
ESAKA Das. No one, we think, can read this paragraph, after having confidered the appearances in the experiments defcribed theoladh above, without recollecting inftances, in fome one or other of them, of almost all the effects of this fluid, enumerated it and agreeing with us, that the other appearances among electrified bodies, as well as that of their repelling and attracting light bodies that are near them, may all of bland rife force and action of this Auid, component particles of the bodies on the rays of light within them; and on the air they are in ; and the reaction within the aether.
of there on
• When a flint and steel are struck together with fufficient force and velocity, a fpark of fire, as we call it, is produced, which readily fires gunpowder, or lights tinder: but Cools if left to itself, sorborg ai bmer:
Now, if fuch a fpark be caught on a fheet of paper, and examined in a microfcope, it will be found to be a piece either of the flint, or of the steel struck off, fo exactly fpherical, and polifhed, that the windows of the room may be feen in it, in the fame manner as they are in a large polifhed fphere of metal or glafs and they could not be fo fpherical, and well polifhed, as they are found to be, if they had not been melted, and kept in this form by the cohelion of their Component particles.
In either of these cafes, a piece of flint or fteel, is evidently feparated from the body, and its component particles puts put into fuch agitations among each other, as to throw off the rays of light which were among them, and shine, and melt, and afterwards cool in a spherical form: by the action melt, ther of the æther on light and air, and thefe component particles; and the reaction of these upon the æther; on their being all put into action at once, by the brifknefs of the ftroke.
There would have been no fuch fpark produced, if any of there had been wanting; and, confequently, they are all neceflary, tho, perhaps, not equally fo, to the producing this effect; the æther feeming to be as powerful an agent as DE as any amongst them; without which the inteftine motion among the component particles of the piece ftruck off, could not have been kept regularly up, even for the very fmall time in which thefe changes are made in that
In the fame manner are the appearances of light in thefe • electrical experiments, whether in faint ftreams of different colours, or in bright and active fparks, to be confidered; as arifing from fmailer parts of grofs bodies feparated from them, and carried off by the activity of the excited æther, paffing from one body into another; which parts, tho' imperceptible to us, muft have their component particles put ⚫ into agitations amongst themfelves; and, in being decompofed, part with the light (that before lay hid within them) and their moft volatile particles; and fo fhine, and fmell, • and explode, in paffing through the air.
And not only thefe appearances of light, fparks, and ex1} plofion, but the effects of them on bodies, expofed to them in electrical experiments, feem all to be explicable by the mutual action and reaction of the aether, of the component particles of the fmall parts of bodies thrown off in thefe experiments, of the particles of light within thefe, and of the air, one upon another, when they are once made active by • friction.
We fhall conclude this article with the, following curious. difcovery made by thefe Gentlemen, namely, that the weight of a chain is not fufficient to bring the links of it into contact with each other, but requires a very confiderable additional force to perform it. We mention this as it has aftrong tendency to confirm what the late ingenious Mr. Melvill ob ferved, to wit, that the drops of water on the leaves of colewort, do not in reality touch the plant. See our laft Review, page 382, feq.
To the AUTHORS of the REVIEW.
Writer is never fo effectually confuted, as when he is made to confute himself.-The learned Dr. Patten, in his Reply to Mr. Heathcote, (page 3.) after having given it as his opinion, that the fcience of theology was at its utmoft fection about the beginning of the laft century, goes on thus. "The volumes, I mean, of Jewel, and Jackfon, and Andrews, and Reynolds, and Hall, and Taylor. Thefe glorious defenders of Chriftianity would have pitied, inftead, "of abetting, the attempts of thofe writers, who undertake,
with the fhallow line of human conjecture, (the true name "of Reafon partially informed) to fathom the deep things of "God, and who concede to infidels, that nothing is to be