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we have so many undoubted testimonies of the disgust at life, which prevailed, or was openly affected at least, by the ancient nations.
In our author's third book, he treats of the Eleufinian, and other ancient mysteries, with the motives of their inftitution; of the Sybilline oracles, and of the astrological theology, or natural religion of antiquity.
In the fourth and last book, he treats of what he calls the Esprit Cyclique of antiquity, or the notions of the ancients regarding astronomical revolutions, and the approaching period of the world : of the moral and religious tenets to which those notions gave rise, and the customs which prevailed accordingly. His observations on all these subjects are for the most .part novel and ingenious : but how far they are justified by authentic history, we pretend not to determine.
Histoire de l'Academie Royale des Sciences et Belles Lettres de Berlin,
The History of the Royal Academy of Sciences and Bellas
Lettres at Berlin, for the Year 1758. 4to. Berlin 1765.
HE publication of the history of the academy of sciences
at Berlin, having been interrupted by the late war; the materials, arising from the constant application of its members, have accumulated to such a degree that the academy now propose to publish two volumes yearly till they make up the deficiency to the current year. In consequence of this resolution, we are promised, in the present publication, the speedy appearance also of the volume for the year 1764.
Our Readers will doubtless recollect the order in which the memoirs of this academy are published, agreeably to the four classes, into which it is itself divided ; viz. Physics or experimental Philosophy, geometry or the mathematics, metaphysics or speculative philosophy, and literature or the Belles Lettres.
Under the first head, we have in the present volume, eight papers, the first, containing a chemical enquiry into the effects of the alkali of common talt on the regulus of antimony, by the celebrated Mr. Marggraff. It is well known that antimony is compounded of a metalline subtance that forms the regulus, .and of sulphur: the separation of these two substances is effected by various methods, as by means of other metals, falt and alkaline earths. In the first case the metallic part of the antimony always retains fore impurity, proceeding from the metal made use of in the separation ; in the others it comes out
more pure, and therefore better adapted to the purposes for which the metallic part of antimony is intended. But, as a very fmall quantity only is to be obtained by the means of falt, another method hath been discovered to separate this metal from its fulphur: this is by burning the antimony, and reducing it to its metalline state by combustible substances. It was thought 'necessary to premise, that Mr. Marggraf made use of the latter 'means, to obtain the regulus, on which he made the several experiments here recorded; the particulars, however, we cannot here enumerate.
The second paper is written by the same academician, and contains some experiments on the stone denominated Lapis Lazuli. In these experiments it is observable that the fine blue colour of this stone, is not to be changed even by calcination. Mr. Marggraf determines, in contradiction to some other writers, that po copper enters into the composition of the Lapis Lazuli; but rather a small mixture of iron.
Memoir the third contains a chemical examen into the ore of a silver mine ; consisting of mineral leaves, or thin flakes of that metal; and is described as a combustible, dark-brown, flexible and light substance. This description and examen are written by Mr. Lehmann; the Author likewise of the fourth memoir, containing historical and chemical researches into the nature of gum copal ; which this ingenious chemist ranks, on the authority of a number of experiments, among those dry bitumens which approach the nearest to the nature of amber ; and therefore, a subject of the mineral kingdom.
The fifth paper contains anatomico-pathological observation's on some extraordinary inflations of the abdomen ; proceeding from various causes, and is attributed to M. Mechel. The fixth is a defence of the practice of inoculation, by Count Hedern, in answer to Count Roncalli, president of the medicinal College at Brescia. It were superfluous in us to quote any of the arguments here made use of, but we cannot pass over a little anecdote which the Count relates to his antagonist; but for whose authenticity we will not be accountable.
" It is not thirty years ago, says he, since a sermon was preached against inoculation in the very church, in which the Bishop of Worcester hath in our times' delivered a noble and convincing discourse * in favour of it:notwithstanding the learned and pious orator, his predeceffor in the same pulpit, declared inoculation to have been first practised by Satan on the person of Job." Whac authority this good parson had for asserting the distemper of Job to be the small-pox, or where he learned that he received it by inoculation of the Devil, we cannot fay; but if thefe Atrange circumstances be true, the amictions of Job mult have
been fingular indeed, to have the Devil himself both for tormentor and physician.
In the seventh memoir, Mr. Gleditsch, well known for his botanical researches, hath given the public fome ingenious and curious remarks on the oblervable conformity that sublifts between the vegetable and animal kingdoms. In the eighth, Mr. Spielmann gives an account of the Bitumen of Lampertsock, a village in Alsace, near which a fetid, black, bituminous substance issues out of the earth in great abundance; the oil drawn from which substance, by distillation, Mr. Spielmann is firmly perfuaded to be the real Naphtha of the ancients.
In regard to the SECOND Class, viz. the mathematical pursuits of this celebrated academy, they seem at present to depend almost entirely on the talents and industry 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 justly observed that the science here cultivated is the foundation of all practical mechanics; før how should 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 disposed throughout the whole of their extension? 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 designs. Mr. Euler conceives, however, that the notion of a centre of gravity, is in general not sufficien:ly exact and precife. It is commonly supposed 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, passing through such center, the parts thus divided must be equally heavy *.
This, he observes, would be very true, in respect to a globe or homogeneous cylinder ; but in a cone, however homogeneous, it would be notoriously false ; for, its center of gravity lying in its axis, at the distance of a fourth part of its height from the base, if such cone be divided in a plane parallel to its base, and passing through its center of gravity, the upper part will bear a proportion to the whole as 27 to 64 ; so that it will be considerably less than one half. Again, if the bodies are not homogeneous, it rarely happens that the sections, made by passing through their centre of gravity, divide such 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 observed that those, who can form such a mistaken conception, must know very little indeed, either of the theory or practice of mechanics,
that we cannot justly conceive the mass or weight of a body ac cumulated in its common centre of gravity, unless when such body is in perfect equilibrio, or when it moves in such a manner that the progression of all its parts is equally quick during the fame instant, and in the same direction. When a body moves about an axis, such supposition 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 mass was united in its centre of gravity. Hence arises our attention to that other point which we call the centre of oscillation"; and from hence occurs the ex, pediency, suggested by Mr. Euler, of separating our idea of the centre of the inertia of a body from that of its centre of gravity.
Memoir the second treats of the motion of solid bodies, revolving about a changeable axis.
The third contains some general remarks on the diurnal motion of the planets; the difficulty of forming a just conception of which, hath been sufficiently experienced by those who understand the subject : nor, to say the truth, do we think Mr. Euler hath been very successful in his attempt to elucidate it.
There are foạr other memoirs belonging to this class; three of them on algebraical and geometrical subjects; the fourth on the motions of a globe on an horizontal plane, by Mr. Jean-Albert Euler, eldest son of the geometrician above-mentioned : but want of room obligeth us to proceed to the THIRD CLASS of subjects, treated of in this academical history. The first of these is entitled The discovery of the laws of a cypher of the late professor Hermàn, which was judged to be undiscoverable. The late professor 's Gravefande, who was himself an able decypherer, at the same time that he was one of the best mathematicians and mechanics in Europe, speaks much in favour of the utility of this study, even setting aside the immediate uses to which the art of decyphering is applied. He thought, indeed, it might be of great and real service, in directing the mind to the just application of the first principles of metaphysics. To thole who are of Mr. 'S Grayefande's opinion, this article may not prove disagreeable.
The second memoir, in the class of speculative philosophy, relates to the nature and discovery of the Moral sense; on which fome philosophers have of late lo largely expatiated. This piece is written by Mr. Merian, and is composed confessedly as a soJution to the following question...“ 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 philosophers, who have treated this subject with the moft fuccess, may be distinguished into two claffes; the one confifting of those who have imputed the knowlege of moral good and evil to the understanding or the light of reason; and the other of such as have attributed it to immediate sensation, a kind of physical sense which they call moral sentiment. The vestiges of this last principle, it is observed, may be traced in the philofophy of antiquity; but hath never been fully explained or illustrated, till the present century: the honour of doing which was reserved for the philosophers of Great Britain and Ireland. Lord Shafisbury was the first modern professor of the doctrine of moral sentiment; although he does by no means treat of it with the methodical acidity of a theological profeffor. Not content, says Mr. Merian, with embellishing it with the charms of a divine * eloquence, and a poetical sublimity of stile ; he seems to have been so strongly affected with this sentiment himself, that we are more in danger of being seduced by his enthufiasm than convinced by his arguments. Hutcheson, who fucceeded Lord Shaftsbury in the same route, reduced this principle to a greater degree of precision; and Hume hath endeavoured to confirm that by fact and experience, which his predecessors had deduced from reason and speculation.
The subject of this memoir is divided into three parts. In the first, the Author enquires whether this moral sense may justly be deemed a philosophical principle? In the second, he compares it with self-love; and in the third, with the principles of that morality which is founded on reason or argument. The following extract may give the Reader some idea of Mr. Merian's manner of treating these difficult and delicate subjects. " It hath been pretended by many, that nothing can truly be denominated virtue, which we do not love and admire solely for its own sake. But this is a mistake; or rather the whole dispute about self-love and social, or pure and disinterested affection, is a dispute about words. There can be no doubt that we love, for our own sakes, all those 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 i consists. Hence it is that we always love those objects, which S are Aattering to our senses, and that we love and approve what Ewe call virtue. On the same foundation also rests that cele.
brated saying of the ancients, that Virtue is its own reward,
• It may not be impertinent, though it may be thought a little tude, to ask a Writer who pays our nation such high encomiums, whether he underliands our language well enough to judge of the divine eloquence of Shaftsbury? We are afraid this extravagance of eulogium is paid at second hand; but, be it as it may, we think a more moderate liga of approbation would do us more honour. The file and manner of Shaftbury are truly admirable: but there is nothing divine in the case. App. Vol. XXXIII.