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Experiment fixth, of chapter fixth, is, in our opinion, a ftrong confirmation of the Franklinian theory, inftead of being, as the author defigns it, a confutation: his only objection is, how comes it to pass that there is a condenfation upon the outside of an infulated jar applied to a conductor charged negatively? This will depend upon a variety of circumstances; his want of cleanlinefs and accuracy, the fize of his knob, and the state of the air at the time. We have often found, after much wiping has been employed, that a knob would, in a cafe fimilar to what the author has defcribed in this experiment, discharge a brush almoft with every turn of the cylinder into the air; it is true the quantity is but small, and, in our opinion, this is the very caufe why the jar at the pofitive conductor is not wholly difcharged. Had there been a better conductor to carry it off from the infide of the fecond jar, all the phenomena Mr. Lyon defcribes would have been, fhewn in much greater perfection, and the whole of his experiment would be nothing more than one of the most antiquated facts relating to the Leyden phial. We would farther obferve, that the author feems to have thought that the infulated table itself took away none of the fluid from the jar at the prime conductor. We are inclined to think, that if, inftead of this clumfy method of infulation, he had made use of dry glass only, or wood well baked, he would not have discovered fo much, either to puzzle or lead him aftray; indeed the impertinent incumbrance of appendages to his apparatus in this experiment would alone lead us to fufpect his accuracy.

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Chapter seventh begins with a declamatory Philippic against the Franklinian theory, as fubftituting in feveral places fuppofition for demonftration, and as twifting and torturing experiments to correspond with the hypothefis, rather than the hypothefis being proved by experiments to be fufficient to pafs for a general law.' Concluding this exordium with a bold metaphor, he proceeds to prove by experiment, that the bruth, which appears at the point of a charged conductor, is no proof that the fluid paffes out of that point, nor the ftar, as generally believed, of its entering into it. If we repeat the experiments of this chapter, we must repeat our accufations of inaccuracy, inattention to the infulators which are employed, with various other fources of error, which this author has the talent of exemplifying and diverfifying in a moft copious manner. We cannot, however, pafs over the fingular degree of confidence which is displayed in experiment fifth, and the fingular manner with which it is fupported. To the end of an infulated metal rod he cements a dry globe of glafs; by a point which terminates the rod he conveys the

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fluid on the inner furface of the globe: during the operation, he defires you to prefent your finger, or the back of your hand, to the external surface of the globe; and, he says, that you may both fee and feel the electric effluvia paffing from the wire through the glass to your finger.' It cannot be fuppofed, continues the author, in this experiment, that the fluid paffes from your finger through the glafs to the point of the rod, at fuch a fuppofition, the most fanguine advocate for the pofitive and negative electricity would bluf' The author does not confider that the globe, in this experiment, acts as a Leyden phial, is negative on the outfile, and of course must appear to emit fome of the fluid from the furface to his hand. If he is dif pofed to feel whether this be true, we would advise him, whilst one hand is applied to the external furface of the globe, with the other hand to touch the infulated rod. Before he affumes the peremptory ftyle of his remarks on this and the following experiments, in which he is mifled by the fame fallacy, he muft account for the poffibility of charging any piece of dry glafs, in the circumftances in which a globe is placed.

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Chapter eighth contains a fet of experiments, to fhew the fimilarity of the magnetic to the electric attraction and repulfion. Our remarks on fome preceding experiments will affect his deductions from fome of thefe; as to the author's application of the reft, both the poignancy and aptitude feem to be equally invifible. He lays no claim to novelty in most of what he produces in this chapter; the new part, in our opinion, is the only doubtful one; but as to the conclufion drawn from the whole, what it means, or what it is defigned for, is totally involved in obfcurity. From the fimilarity, fays he, there appears to be between these electric and magnetic experiments we may reasonably conclude, for there is rather more than a probability, the effluvia of both act from one principle, and that there is a polarity in these infinitely and inconceivably fmall particles of matter. We find, in certain cafes, the electric particles as well as the magnetic attract each other, and they will unite with an inconceivable velocity; and in other cafes they as powerfully repel. This cannot be done without fome inherent and innate property in the particles of the electric effluvia -I imagine this property exist in the first particles of matter, without a directive tendency to one particular point of the horizon. Nature seems to favour this doctrine in a variety of instances, as will be shewn in a proper place *. As I believe it will be a difficult, if not

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* This proper place we have not been able to discover throughout the whole quarto.

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an impoffible task to draw rational and confiftent conclufions from many electric appearances without the affiftance of this theory, I shall endeavour to fupport it in preference to any other.'

Chapter tenth is faid to contain an analyfis of the Leyden phial, with a variety of experiments, to fhew the dif charging of it depends, moft probably, upon an attractive and repulfive property inherent in the particles of the electric effluvia; and that this wonderful phial may act from the fame principle as the magnet, or the loadftone.'-This chapter is in truth a curiofity; it claims our admiration of Mr. Lyon's talents, not only as an experimentalift and a fpeculatift, but as a moft defcriptive declaimer. Let his fixth experiment be read as one felected from many, equally expreffive of the author's talents. - Fill a coated jar, with boiling water up to the top of the infide coating of the jar, place it in a glass vessel, and fill the veffel with boiling water, till it rifes as high on the outfide as it is in the infide of the jar. Place this veffel upon a ftool with glass legs, with the knob of the wire of the jar in contact with the conductor of the electrical machine; while the jar is charging, prefent a conducting rod to the outside of the glafs veffel, and when charged, take the discharging bow, and form a communication between the outside of the glafs yeffel upon the ftool and the knob of the wire of the jar, and if you darken the room, you may fee the electric effluvia shoot upon the outfide of the glafs veffel, into beautiful ramifications, from the knob of the discharging bow. Some of the largeft branches fometimes fhoot between two and three inches long, and fhow, in miniature, the zig-zag and forked lightning, which ftrike fuch terror into the breast of the bewildered traveller in a dark and tempeftuous night. No words can convey an adequate idea of this experiment.'

We affent to the juftice of this concluding paragraph; the experiment, as he calls it, bids defiance to all the severity of criticism; it is one of those originals which the most malignant fatirist cannot carricature.--We claim to ourselves great merit for the patience which has carried us through the remainder of this volume; but we have no right to expect the fame patience from our readers; efpecially when, from woeful experience, we are able to inform them that the first ten chapters are not the most abfurd in the book. Like feveral of his betters, Mr. Lyon is phlogiften mad towards the conclufion of this volume. All the phænomena in nature are traced ultimately to the fame principle, which is employed by Mr. Lyon to account for fome of the difficulties in the Mofaic account of the creation. In this particular, however, and in a variety of others, which

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may be pointed out, we would recommend a philofophical partnership between Mr. Lyon and Mr. Harrington; a specimen of whofe uncommon abilities may be seen in the following article.

A Philofophical and Experimental Enquiry into the first and general Principles of Life: likewife into Atmospherical Air. By Robert Harrington. 8vo. 6s. Cadell.

MR. Harrington, in his introduction, gives a catalogue of his accomplishments as a philofopher; he seems afraid to truft the fagacity of the reader in this particular, and exhibits a daubing as a reprefentation of himself, in which a group of features are jumbled together, not one of which could have been discovered from any part of his work. Accipe digni pauca notanda viri.

6 A young man, when he takes up fo learned and extensive a fubject, and when he has to combat with the opinions of the greatest men, requires a deal of refolution; but I hope my readers will give an impartial canvas. It is a work of indefatigable labour, where you are to build a fyftem of your own; a fyftem which comprehends all the different fciences, viz. natural philosophy, anatomy, phyfic, chemistry, mathematics, &c. and not only to be well acquainted with these, but even to correct their errors, and make new improvements in each; otherwife I could not have established this extenfive doctrine. And to do all this myfelf, without having any perfon to affift me, or to afk a fingle queftion of; being tenacious about difcovering any part; having, from experience in one or two inftances, found my confidence betrayed in my philofophical enquiries.' We affure our readers that this quotation has been made with all poffible accuracy, and, we think, to render it complete in its kind, nothing is requifite but a little false spelling.

We no fooner begin to examine the book, than we find ourfelves furrounded with fuch abfurdities, that we know not which to fix upon as the moft glaring and extravagant. Hear him ⚫ premife (what he calls) the hiftory of the animal. There are two genera in nature which make up the principal part of the creation upon the globe, being the animal and vegetable kingdoms; we evidently obferve they both enjoy life.-Life is a very vague term, when applied in this philofophical sense; but what I imply by it is, a body having a power of extenfion within itself, being produced from an ovum, by copulation of the fexes, which generates to maturity, and being then capable of propagating its fpecies.' We are inclined to think that Linnæus himfelf would be puzzled to find what animal

this curious defcription refers to; this is the first instance in which we have heard the appellation of genera given to kingdoms, and of life being a body produced from an egg, and that the prolific egg is laid long before the parents have copulated.

The author's definition of air is not lefs curious than his

hiftory of the animal: Air, says he, is an æthereal, subtle, and elastic fluid, universally dispersed over the whole face of the earth, ftrikingly reprefented by the down of the peach, for fo does the air cover the furface of the globe, as the down does the peach.' We rather think Mr. Harrington supposes that the air is like a goat's beard, for as the beard covers the chin of the goat, fo does the air cover the furface of the globe. Through the whole of this work the author miftakes phlogiston for heat, and heat for phlogiston; he confequently afcribes the fluidity of water to a principle, to which (if there be any truth in chemistry) water has no affinity; he talks, likewife, of determining the quantity of phlogiston in a body by the thermometer, and gives us the following account of the cause on which elasticity depends! • Let us enquire upon what elafticity depends. All fluids have this property in fome degree; but it will be found, that those which poffefs moft phlogifton have it moft fenfibly *; fpirituous fluids, for this reafon, poffefs it more confiderably than water; but even water, by giving it a large quantity of phlogifton, can poffefs this quality in a very eminent degree; take a few drops of water, place them in vacuo, and throw into them a large quantity of phlogifton, and their elafticity will overcome the greatest force.' Such is the wonderful penetration of Mr. Harrington, that he affures us, that, if the whole atmosphere could be decompounded at once, the phlogiflon that would be let loofe, would be fuch an immenfe proportion, as to fet the whole world on fire: we often fee, fays he, when there is too ftrong a folution of phlogifton in the atmosphere, that it purges itself by lightning; and in hot climates, it will tear up trees, caftles, nay rocks; for, agreeable to the laws of nature, whenever there is an overproportion of phlogifton in the air, he takes that method to unload herself.' What an uncivil lady is dame Nature, to unload herself in this rude, obftreperous, and public manner!

The great use of refpiration is one of the most curious difcoveries of Dr. Priestley; who fays, that the lungs are employed in this operation to carry off that fuperabundant quantity of phlogiston from the blood, which, if not thus dif

* If this be true, why have oils fo little elasticity?

charged,

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