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the idea of change, by the changed attention of the mind, in conceiving those different places fuccefsfully. This is the most simple idea of motion, abftracting the confideration of time, which is only required in order to determine velocity; therefore, in the present cafe, where the confideration that is made of motion may be restricted to direction, the conception of time is not effential as is that of number.'

It is furprising to hear a metaphyfician talk of the conception of time not being effential to motion, when fucceffion is, a part of the idea. What is the idea of fucceffion without that of time?

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Dr. Hutton next confiders gravity as known from its effects, as a preffing and a moving power, and as a power directing projectiles. He afterwards purfues this principle to the planetary fpheres, and examines its influence, reafoning fometimes accurately, fometimes erroneously, or obfcurely. It is not neceffary to purfue his reafoning, either from the importance of the conclusion or the application. The former is only, that gravitation is general, not proved to be an univerfal property: the latter we shall soon see.

The third Differtation is an inveftigation of the principles of volume in material things, and heat and cold are firft examined with refpect to the conditions in which these fenfations are felt, and to certain appearances with which they are neceffarily connected, with a view of forming a theory of heat and cold. On this fubject, our author falls into the errors of Mufchenbroeck, and various authors of the feventeenth centu ry, who contended, with great eagerness, that the fenfation and effects of cold conveyed an idea of properties as pofitive as thofe of heat: of courfe cold could not be confidered as a privation of heat only. The facts, adduced by Mufchenbroeck, have been repeatedly answered, and our author's reasoning is merely fophiftical.

Cohesion, as a phyfical principle, requires to be inveftigated; but, under Dr. Hutton's aufpices, it is inveftigated with too obvious a bias. He thinks it, like gravitation, a general, but not an univerfal principle: it seems too, in his opinion, to be fubjected to the fame or fimilar laws; in other words, to be the fame principle exerted between the fmaller particles, as fubfifts in gravitating bodies between the larger mafles. Our author's experiment in proof of this pofition we fhail felect, and in part abridge:

A fluid body, having its spherical figure retained by the power of cohefion, may be confidered as urged, by gravitation, to the center of the earth, equally in all its parts. If, therefore, this spherica! body, tending to the center of the earth, fhall be refifted in this di

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rection by a plane to which the fluid fhall have no cohesion, then, here will be exhibited a proper oppofition of cohesion and gravitation, as two powers acting with different intentions or directions. For, by the one power, every particle of the fluid body is made to tend diretly towards the center of the earth; whereas, by the other, all thofe particles are made to tend towards a common center, and preferve a fpherical form. But, as this moving or preffing fpi ere meets with an immoveable or refifting plane, the gravitating power of the body muf tend to change the spherical figure of the fluid, fo far as the power of cohesion will permit. Here, then, each of those two noving powers will have its proper influence on the figure of the body; and, fo far as this figure is a thing fufficiently perceptible, it will afford us an opportunity of measuring the effects of thofe two powers, and knowing their comparative intenfities.'

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We are thus referred to experience, for the decifion of that queftion, with regard to the cohering power; and we are now to compare a ody of mercury, and an equal volume of water, refting upon a plane to which they do not cohere. The question is, how far thefe two bodies full appear to be flattened, cither on the one hand, inverfdly as their specific gravities, that is, the mercury fifteen times more than the water, or, on the other, equally, the mercury being no more flattened than the water.

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The ricans we have to try this queftion are very eafy; for, having poured water and mercury upon a plane to which they do not cohore, (whether from the nature of the fubftance of which the plane is compofed, or by interpofing duft betwixt the fluid and the plane), we have but to measure the height above the plane at which the extending fluid remains.

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According to the theory, this height of the bodies above the plane thould be either, on the one hand, in proportion to their specific gravities Inverly, or, on the other, equal in the two different fluid. In the one cafe, gravitation and cohesion would be powers diftinely different; in the other, again, they would be the fame. Here, then, we have two diftin&t objects in our view; for we have both to try the juftnefs of our theory, and to learn the law of natare. But the event may be different from what we have fuppofcd in the theory, for the heights of the two bodies may be neither in proportion to their specific gravities, nor equal. In that cafe, what fall we conclude with regard to the law of nature, which is the object of our purfait.'

There is, it feems, a perceptible difference between the heights of the two fluids, but by no means in proportion to the fpecific gravities; and confequently cohefion and gravitation are fuppofed to be the fame principle. The experiment, however, is far from being conclufive, and the reafoning is equaily

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antenable. It is impoffible, for inftance, to make the former decifive, fince, if the fluids are equal in bulk, it fails from the difference of the specific gravities: if in weight, the buiks, cæteris paribus, muft occafion a difference in the refult. Profeffor Robinson's calculation, which we have little doubt from other views of being juft, gives a very different conclufion.

'I am indebted to profeflor Robinfon for a very valuable obfervation in relation to this fubject. By calculating, according to the law of gravitation, the fize which a fphere of water should be of, in order to preferve the particles of water from falling, from its under furface, to the earth, he found that this fhould be about nine feet diameter. But we know, that, in the finalleft fphericle of water, the particles cohere. It would therefore from this appear, that the power of cohesion is a power of greater intensity than that of gravitation, contrary to what I have now endeavoured to demonitrate.'

The third chapter, on the principles of volume in bodies, commences with the following very exceptionable pontion, probable only on the idea of cohcfion and gravitation being the fame principles:

Heat being confidered as a principle of expanfion in bodies, and this fpecies of matter being in its nature transferable, as acting upon feparating principles, gravitating matter must be confidered as being the fixed or permanent fubftance of bodies, and as acting in the oppofite direction to that of heat, or as tending to diminish the volume of bodies.'

This antagonizing power of heat to gravitation is, however, adduced to explain the incompreffibility of bodies, the determined bulks of given bodies, and electricity. In our ideas of matter too, we are told, that we must throw afide volumy or determined extenfion; for power and action, or more fimply motion, is alone neceflary to give the proper idea of matter.-Some vague trifling ideas on the effects of heat, as influencing the volume of bodies, conclude this Differtation.

Some apology may be neceffary for infifting fo long on a, work, which appears to deferve fo little of our attention. Yet, as we have said, the fubject requires a new examination; as it is a bulky, and apparently an important fupport of the dying caufe of phlogiston; as Dr. Hutton, in his own circle, is of fome confequence, we have been led farther than we intended. Not, however, to weary our readers with a dull fubject, we fhall take an opportunity of returning to this work in another Number.

Curiofitics

Curiofities of Literature. Vol. II. By I. D'Ifraeli. 8vo. 75. Boards. Murray. 1793.

THE

HE fuccefs of the author's first volume has encouraged him to produce a fecond, which probably may lead to a third; as it will be no very difficult task for a laborious reader, who turns over the pages only of fuch writers as are almoft forgotten, or of manufcripts that are not of fufficient importance to merit publication, to collect Curiofities of Literature, till the ignorant fhall ceafe to wonder, and the curious fhall be completely gratified. Of the prefent volume it is fufficient to fay, that it is at leaft equally entertaining with the former.

We muft add, however, that we do not perceive much intrinfic importance in the materials that compofe this volume, Some of them may justly enough be called Curiofities; but they are the mere cockle-fhells of Literature. They confift chiefly of the follies, fuperftitions, blunders, and quarrels of paft ages. We except, with pleasure, fome choice morfels of Criticism and Hiftory, as well as many Biographical Anecdotes.

We are forry to discover, in some parts of this work, a few flight indications of that fneering infidelity, which after times, perhaps, will diflinguifh by the epithet of Gibbonian. For inftance, relating fome extraordinary anecdote of fuperftitious ignorance, our author characterizes it by the expreffion of pious ftupidity. Should this, however, be only a filly affectation of language (which we hope it is), we would whisper in his ear, that pious' is not the proper epithet of stupidity; and as to any thing like irony or ridicule on fuch fubjects, we fhould condemn it in the fevereit terms, even were we Freethinkers ourfelves; not only as exhibiting a depraved tafte, but as a base and infidious mode of conveying fentiments ads verfe to religion.

We shall extract a few of the most entertaining articles for the amusement of our readers:

• Grammarians -The ancients understood by the title of gram marian, a fcholar very different from those whom the moderns diftinguish by this name. By grammarian (obferve the learned authors of the Literary Hiftory of France) they defcribed a man verfed in literature, who knew to write or speak, not only with correctness of language, but with fkill and elegance. A grammarian, and a fcholar who taught polite literature, were fynonymously expreffed : it is for this reafon Aufonius gives indifferently the titles of grammarian and philologist, or lovers of erudition. In the fourth century, the college of Bourdeaux bore fo fplendid a reputation for the number of its grammarians, that the learned of foreign countries crouded

crouded there to feek for employment; infomuch that the other towns of Gaul, and even those of Rome and Conftantinople, were defirous of having its profeffors, or at leaft fome of its scholars, to teach amongst them. By what appears in Aufonius, the college was common to Christians and Pagans; the fair sex also fitquently took public leffons there.

No grammarian or profeffor of polite literature was ever known, however, to accumulate a fortune; fo much did their fate resemble that of the literary men of the prefent age!--The following anecdote will ferve as an instance:

Urfulus, a celebrated grammarian, taught grammar at Treves, under the reign of Valentinian the First. The fchools were then in a flourishing state. The court was generally held there; which circumftance attracted the most able profeffors, and great numbers of scholars. Aufonius followed it in the character of preceptor to the young Gratian (afterwards emperor). He was long united in friendship with Urfulus, and by what appears in the epiftles of the latter, was always defirous of rendering him fervice. It had long been a custom with the emperors, at the commencement of the year, to bestow money, or other prefents, on those whom they honoured with their notice. The profeffors who had the care of inftructing youth generally partook of this liberality; more particularly those who were near the court. It happened, one year, that Urfulus was forgotten in the diftribution that was made of the largeffes of the emperor; on which occafion he had recourse to his good friend Aufonius. The perplexed manner in which Aufonius Explains himself on the number of crowns which he obtained for Urfulus, has embarraffed very much the learned. Yet, upon the whole, all his studied expreffions do not fignify any thing more than the number of twelve! Yet this man devoted fix hours of every day to the inftruction of youth in literature.'

"Dutch Theatre:-The celebrated Vondel, whom, as Marchand obferves, the Dutch regard as their Æfchylus, Sophocles, and Euripides, has a strange defective tafte. The greater part of his tragedies is drawn from the Scriptures; all badly chofen and unhappily executed. For inftance, in his Deliverance of the Children of Ifrael, what must a man of taste fuffer, when he obferves that one of his principal characters, is the Divinity? In his ferufalem Deftroyed we are extremely fhocked and difgufted, with the long and tedious oration of the angel Gabriel, who proves theologically, and his proofs extend through nine closely-printed pages in quarto, that this deftruction had been predicted by the prophets. And in the Lucifer of the fame author, the fubject is grofsly fcandalifed by this haughty fpirit becoming ftupidly in love with Eve, and it is for her he causes the rebellion of the evil angels, and the fall of our first parents. Poor Vondel kept a fier's fhop, which he left to the

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