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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
Cention 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. dan gitse a
Obfervations on a Series of Electrical Experiments By Dr. Hoadley, and Mr. Wilfon. 4to. Is. 6d. Payne. A
F fubtile difputations, founded on arbitrary hypothefes, could have given fatisfactory reafons for the phænomena of Nature, the doctrine of the fchoolmen, or the principles o 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 philofophizing, 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.
29164 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 he called Ether: That this æther is much rarer within t 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 diftances, it perpetually grows denfer and denser, and thereby causes the gravity of those bodies towards one another, and of their parts towards the bodies; every body endeavouring to go from the denfer parts of the ether, 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
the particular make of that body it is in. e. gr. It is not fó dente in denfe bodies as in rare ones. Such are the properties of the æther, according to Sir Ifaac, but as he was not able to prove fatisfactorily
his followers had the existence of this fine fluid, most of
his followers have denied it a place among the principles of the Newtonian Philofophy."
sift 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 caufe of all electrical phænomena; that the electrical fluid is not elementary fire, as many have fuppofed; 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. bar 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 fluid 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 Ether; that it is as fubtle and elaftic in its nature, as æther is; and, as æther does, that it pervades the • pores of all bodies whatever, that we are converfant with; is difperfed thro' whatever vacuum it is in our power to pro*duce by art; and from the natural phænomena of thunder, lightning, &c. feems to be extended to very great diftances. in the airs dow
25bowe 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 manner of occafion, ad 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 neart them, in the fame manner as amber does when it is rubbed. But this fluid not only makes light bodies, that are • near an electrified body, fly to and from that body, and fo appear to be attracted and repelled: but it heats them, by • putting
Hood endigt god mungia 2325i cuda < 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, burft out into parks of real culinary fire, as the chemills exprefs themselves; nay, more, in paffing through canimals, it occations 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 ⚫after become incorporated, and form an enam enamel.
1 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 a put into fo regular a motion, as to convey fuch fenfations, by means of the ear, 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 it; nor, indeed, can fire be called a Principle, or Element, in the chemifts fenfe of the word, any more than found radio dana poorer rousios dout out the feEns Sir Ifaac Newton, at the end of the Principia, in the feCcond edition, anno 1713, defcribes this fluid, and its effects, in the following words; and fays, exprefsly, that it is the caufe of the Electricity. ißem ed: bat Adjicere jam liceret nonnulla de fpiritu quodam fubtilif"fimo corpora crafla pervadente et in iiidem latente: cuj cujus vi, et actionibus particulæ corporum ad minimas diftantias fermutuo attrahunt, et contigua facta coherent: et corpora electrica agunt ad diftantias majores tam repellenda quam attrahendo 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 nervorum 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,
on Electrical accurate determinare Experiments.
quibus leges actionum hujus fpiritus 66 et monftrari debent.seeing in
confe, we think can re
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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; 6 as arifing from smaller 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 smell, and explode, in paffing through the air.
And not only thefe appearances of light, fparks, and exC 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 æther, 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 a strong tendency to confirm what the late ingenious Mr. Melvill obferved, 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.
Writer is never fo effectually confuted, as when he is made to confute himfelf.-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 utmost perfection 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 glo"rious 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 4. God, and who concede to infidels, that nothing is to be "received,"