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been fingular indeed, to have the Devil himself both for tormentor and phyfician.

In the feventh memoir, Mr. Gleditfch, well known for his botanical researches, hath given the public fome ingenious and curious remarks on the obfervable conformity that fubfifts between the vegetable and animal kingdoms. In the eighth, Mr. Spielmann gives an account of the Bitumen of Lampertslock, a village in Alface, near which a fetid, black, bituminous fubftance iffues out of the earth in great abundance; the oil drawn from which fubftance, by diftillation, Mr. Spielmann is firmly perfuaded to be the real Naphtha of the ancients.

In regard to the SECOND CLASS, viz. the mathematical purfuits of this celebrated academy, they feem at prefent to depend almost entirely on the talents and induftry of the celebrated Mr. Euler; who hath furnished the three first papers of this kind. The first is entitled researches into the mechanical science of bodies. It is very juftly obferved that the fcience here cultivated is the foundation of all practical mechanics; for how fhould we be able to determine the motion of bodies, without knowing both the quantity of matter they contain, and the manner in which it is difpofed throughout the whole of their extenfion? It is, indeed, from this mode of investigation that we deduce the idea of a center of gravity; the knowlege of which is so very important in the execution of all mechanical defigns. Mr. Euler conceives, however, that the notion of a centre of gravity, is in general not fufficiently exact and precife. It is commonly fuppofed that there is an equal distribution of matter, or weight, about a certain point; which is therefore called a centre of gravity; and hence it is almost as generally conceived that, if we divide any body in a plane, paffing through fuch center, the parts thus divided must be equally heavy *.

This, he obferves, would be very true, in refpect to a globe or homogeneous cylinder; but in a cone, however homogeneous, it would be notorioufly falfe; for, its center of gravity lying in its axis, at the diftance of a fourth part of its height from the base, if fuch cone be divided in a plane parallel to its bafe, and paffing through its center of gravity, the upper part will bear a proportion to the whole as 27 to 64; fo that it will be confiderably lefs than one half. Again, if the bodies are not homogeneous, it rarely happens that the fections, made by paffing through their centre of gravity, divide fuch bodies into equal parts either with regard to bulk or weight. Add to this

• With due deference, however, to this famous geometrician, it may be obferved that thofe, who can form fuch a mistaken conception, muft know very little indeed, either of the theory or practice of mechanics.

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that we cannot justly conceive the mafs or weight of a body ac cumulated in its common centre of gravity, unless when fuch body is in perfect equilibrio, or when it moves in fuch a manner that the progreffion of all its parts is equally quick during the fame inftant, and in the fame direction. When a body moves about an axis, fuch fuppofition never takes place; thus it is well known that the motion of a pendulum is very different from what it would be, if its whole mafs was united in its centre of gravity. Hence arifes our attention to that other point which we call the centre of ofcillation; and from hence occurs the ext pediency, fuggefted by Mr. Euler, of feparating our idea of the centre of the inertia of a body from that of its centre of gravity.

Memoir the fecond treats of the motion of folid bodies, revolv ing about a changeable axis.

The third contains fome general remarks on the diurnal mo→ tion of the planets; the difficulty of forming a juft conception of which, hath been fufficiently experienced by those who understand the subject: nor, to fay the truth, do we think Mr, Euler hath been very fuccessful in his attempt to elucidate it.

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There are four other memoirs belonging to this class; three of them on algebraical and geometrical fubjects; the fourth on the motions of a globe on an horizontal plane, by Mr. Jean-Albert Euler, eldeft fon, of the geometrician above-mentioned: but want of room obligeth us to proceed to the THIRD CLASS of fubjects, treated of in this academical history. The first of thefe is entitled The discovery of the laws of a cypher of the late profeffor Herman, which was judged to be undiscoverable. The late profeffor 'S Gravefande, who was himself an able decypherer, at the fame time that he was one of the beft mathematicians and mechanics in Europe, fpeaks much in favour of the utility of this study, even fetting afide the immediate ufes to which the art of decyphering is applied. He thought, indeed, it might be of great and real fervice, in directing the mind to the just application of the first principles of metaphyfics. To those who are of Mr. 'S Gravefande's opinion, this article may not prove disagreeable.

The fecond memoir, in the clafs of fpeculative philofophy, relates to the nature and difcovery of the Moral fenfe; on which fome philofophers have of late fo largely expatiated. This piece is written by Mr. Merian, and is compofed confeffedly as a foJution to the following queftion. "What is that principle, in the mind of man, which induces him to approve certain actions as morally good, and condemn others as morally evil?" The philofophers, who have treated this fubject with the moft fuccefs, may be diftinguished into two claffes; the one confift

ing of those who have imputed the knowlege of moral good and evil to the understanding or the light of reafon; and the other of fuch as have attributed it to immediate fenfation, a kind of phyfical fenfe which they call moral fentiment. The veftiges of this laft principle, it is obferved, may be traced in the philofophy of antiquity; but hath never been fully explained or illuftrated, till the prefent century: the honour of doing which was referved for the philofophers of Great Britain and Ireland. Lord Shaftsbury was the first modern profeffor of the doctrine of moral fentiment; although he does by no means treat of it with the methodical acidity of a theological profeffor. Not content, fays Mr. Merian, with embellishing it with the charms of a divine eloquence, and a poetical fublimity of ftile; he feems to have been fo ftrongly affected with this fentiment himfelf, that we are more in danger of being feduced by his enthufiafm than convinced by his arguments. Hutchefon, who fucceeded Lord Shaftsbury in the fame route, reduced this principle to a greater degree of precifion; and Hume hath endeavoured to confirm that by fact and experience, which his predeceffors had deduced from reafon and fpeculation.

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The fubject of this memoir is divided into three parts. In the first, the Author enquires whether this moral fenfe may justly be deemed a philofophical principle? In the fecond, he compares it with felf-love; and in the third, with the principles of that morality which is founded on reafon or argument. The following extract may give the Reader fome idea of Mr. Merian's manner of treating thefe difficult and delicate fubjects.

It hath been pretended by many, that nothing can truly be denominated virtue, which we do not love and admire folely for its own fake. But this is a miftake; or rather the whole difpute about felf-love and focial, or pure and difinterested affection, is a difpute about words. There can be no doubt that we love, for our own fakes, all thofe objects, the contemplation. or enjoyment of which gives us an immediate pleasure; for it is, in fact, in the anticipation or enjoyment of this pleasure that love confifts. Hence it is that we always love thofe objects, which are flattering to our fenfes, and that we love and approve what we call virtue. On the fame foundation alfo refts that celebrated faying of the ancients, that Virtue is its own reward,

It may not be impertinent, though it may be thought a little rude, to afk a Writer who pays our nation fuch high encomiums, whether he understands our language well enough to judge of the divine eloquence of Shaftsbury? We are afraid this extravagance of eulogium is paid at fecond hand; but, be it as it may, we think a more moderate fign of approbation would do us more honour. The ftile and manner of Shaftsbury are truly admirable: but there is nothing divine in the case.

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To this we may add that, if the mere contemplation of virtue in external objects is so very delightful, there can be no wonder that it fhould be found infinitely more fo when we behold it in ourselves. It must be confeffed, indeed, that fome of the ancient philofophers, and particularly the Stoics carried this maxim to a ridiculous length. According to their abfurd fyftem, the inward fatisfaction of the true fage, was fufficient to render him infenfible to all the evils of human life; the most excruciating torments of the body, as they pretended, could not affect the internal felicity of his mind; for a truly wife man might be even happy in the tortures of Phalaris's bull. Such extravagant notions as these deserve not a serious refutation:, for might we not as well affure a man, who is racked with the gout or the ftone, that the profpect of the verdant meadows of spring, or the golden fields of autumn, are fufficient to remove his pains? The fenfe of moral beauty, like that of the phyfical, can give no degree of pleafure, which may not be counterballanced, or even effaced by preponderating pains." From thefe confiderations our Author draws a confequence; which, though he thinks it may, at firft, appear a little fingular, he takes upon him to fay, is no lefs juft. This is, that a pure love for virtue, which paffes for fomething fo difficult of attainment, as one of the highest degrees of myftical perfection, and with many as a mere chimera, is notwithstanding the moft common and moft natural thing in the world. Every moral fenfation, fays he, is an act of pure, difinterefted, affection; in which the mind difplays its love for virtue, in confequence of that pleasure it takes, in admiring virtue for its own fake.

The third memoir in this clafs, is entitled the Analyfis of Reason, and is written by Mr. Sulzer; who, in a preceding volume of this history had given the public an Effay on Genius. Mr. Sulzer obferves that the term, reafon, is taken in a twofold acceptation: that is either as the general concatenation of univerfal truths, agreeably to the idea of Leibnitz; or as the fimple faculty of reafoning in the individual, conformably to that of Wolfius. In the firft fenfe, reafon is, in every rational Being, that collection, or fum, of philofophical knowlege it is poffeffed of: in the second fenfe, it is merely the faculty of acquiring fuch knowlege. There are two things, therefore, fays he, to be enquired into, the faculty itself, and the acquifitions of that faculty. With this duplicate view, is the memoir before us compofed; which, though it may afford little novelty or fatisfaction to those who are profoundly verfed in the subject, cannot fail of impreffing a very advantageous idea of the abilities of the Writer on the mind of the Reader.

The last memoir in this clafs, treats of the doctrine of Infi- i nites, and was written by the late Mr. Premontval; a philofo

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pher of much greater ingenuity than folidity; but nil nifi bonum de mortuis.

In the fourth, and laft clafs of this work, viz. the Belles Lettres, we have a differtation on Jodutha, the ancient idol of Saxony and the March of Brandenbourg, by Mr. Kufter: to which fucceed feveral academical difcourfes and eulogies; for which we have no place of insertion.

La Phyfique de l'Hiftoire, &c.

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The natural History of Nations. Or Confiderations on the elementary Principles of the temperament and characters' of different People. 12mo. Amfterdam. 1765.

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HE office of a literary Reviewer is perhaps one of the most ungrateful upon earth; for, whether he find occafion for approbation or blame; or whether he thinks it incumbent on him, in the case of mediocrity, and in juftice to the public, to bestow neither; he is himself morally certain of becoming the object of the fevereft cenfure. It were indeed a ftale fubject of complaint, to mention the vanity of Authors, the partiality of their friends, or the malice of their enemies: we fhall not take up our Reader's time, therefore, with remarks on either of these topics. There is a very ferious and plaufible objection, however, that hath been of late repeatedly made to the conduct of literary journalists, and particularly to the English Reviewers. They are faid to be much too fevere, and farcaftical in their treatment of thofe Authors, whofe Writings are fubmitted to their confideration as a proof of which are brought the more candid and favourable examples of thofe ingenious and learned foreigners, who firft engaged in works of this kind. Le Clerc and S Gravefande, we are told, pointed out the errors of miftaken writers with candour, reprehended even the petulant with tenderness, and spoke of all with politenefs and urbanity. We fhall not enter into a strict examination of the truth of this affertion; there were doubtless among the primitive Reviewers many gentlemen of the moft candid and amiable difpofitions: but we cannot help thinking that their tenderness for individuals much too often clashed with that juftice and impartiality they owed to the public. Add to this, that even the more deferving of the former must be prejudiced, by that indifcriminate mode of treating the most contemptible Writers with the fame ceremony as the most refpectable. But, be all this as it may, the ingenious Authors of the above objections fhould confider that, there hath been a great revolution in the world of letters finçe 002.

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