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and so on-to accumulated instances of absurdity,- This is, indeed, the shameful part of the work before us, of which we may lay in the words of Horace ::

- turpiter atrum Definit in piscem mulier formosa fuperne. . Is it not; in effect, most deplorable and disgusting, to see above an hundred and twenty pages of the most hideous nonsense about transubstantiation, at the conclusion of a book, in which we find order, method, an agreeable manner of treating abstract and speculative subjects, warmth of style and expresion, and a very considerable acquaintance with ancient and modern philosophy? No mortal would think, that the concluding section of this treatise on matter, which considers the connexion between metaphysical science and natural philofophy, could come from the same pen, that was defiling the philofophic page, fome moments before, with the filthy jargon of scholastic thcology:

This last section would be a very proper introduction to a course of natural philosophy; it is short, judicious, and steers a middle way between the vicious method of interpreting nature by hypothetical speculation, and the equally defective one, interrogating her hy insulated and unconnected experiments, that neither lead us to the knowledge of her plan, her Author, nor her end.

ART. III. Histoire de l'Academie Royale des Sciences, &c-i.e. The History and Memoirs of the Royal Academy of Scicoces at Paris for the Year 1773. 4to. 1777.

GENERAL PHYSICS. Memoir. On the Variations of the Magnet in the Years 1772 and

1773. By M. LE MONNIER. TE find, in this Memoir, an account of the methods

V employed by M. LE MONNIER to diminish the error oc, cafioned by friction, in the experiments on the direction of the magnetic needle, more especially in variation compaffes. In what manner soever a needle is suspended, the resistance of the friction prevents its taking exactly the direction which it would have followed, had it played at liberty. This resistance increases in proportion to the weight of the needle, as does also the magnetic power, according to the observation of our acade. mician; and from hence he concludes, that the most perfect needle is not that which is attended with the smallest degree of friction, but that in which the resistance, arising from friction, will be in the least proportion with the directing power. He thinks, it would be proper to augment the magnetic power of the needle by increasing its weight; even though this might sender the reliltance of the friction proportionably greater ; be

cause cause it might be pofsible to correct the error arising from hence; or at leaft, to make a proper eftimate of it. The error might be corrected by following the mean between twa observations that would yield, the one a direction tending too much towards the east, and the other, a direction too much to the welt; and it might be estimated by experiments well calculated, and repeated for each dimenfion, and each degree of weight which it might be thought proper to give to the needle.

The difference, which is observed between the directions, in dicated by the compasses, in places that are little distant from each other, while at greater distances the directions are the fame, form, in the judgment of M. LE MONNIER, a strong proof of the necessity of perfecting still farther the construction of the compass, and of fixing exactly the true magnetic meridian.

M. MONNIER, after several judicious observations on the improvement of this useful instrument, gives an account of the experiments he made with two different compasses, carefully placed, one at the Temple, and the other on the terrass of the Thuilleries. To avoid all error proceeding from diurnal variations, he made his obfervations every day at the same hour, The magnetic needle pointed to Paris, on the side of the east, in the beginning of the last century; it continued to return toward the north until the year 1666, and after that period, it pailed over to the side of the west. It remained afterwards ftationary for fome years, and M. LE MONNIER thinks, he may venture to affirm, that it was so still, in 1773. Observations on the Tides at Madagascar, in the Torrid Zone,

By M. Le GENTIL. Memoir. Concerning the Form of the Bar or Metallic Canductors,

designed to preserve Buildings from the Effects of Lightning, by unveying it into the Earth. By M. Le Roy.

One of the most extraordinary things we meet with in this memoir, is the obstinacy with which the French have rejected the use of metallic conductors, notwithstanding the experimental demonstrations, so often repeated, of their falutary effects. M. Le Roy laments it as a just reproach caft upon his nation, " that is adopts with eagerness the frivolous modes of its neighbours," (he meant, we suppore, invents frivolous modes for itself which its neighbours are foolish enough to imitate) “ while useful difa coveries, whose advantages are ascertained by reason and ex. perience, are scarcely ever employed by his countrymen, before they have been adopted by all the rest of Europe, · The subje&t of this memoir is the form which ought to be given to nietallic conductors. This point was controverted in England a few years ago. Some gave the preference to those conductors which rise but a litile above the building on which they are fixed, and whose extremity is blunt and obtuse: oshers,

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following the opinion of Dr: Franklin, maintained the superior merit and efficacy of those which were more elevated, and pointed : this opinion was followed in the conductors fixed on the powder-magazines at Purfleet : and the memoir now before us, contains a considerable number of experiments, that confirm it in the strongest manner. The result of these experiments may be contained in the following propofitions :-That it is erroneously asserted, that the painted conductors draw the lightning sooner' from the clouds, than those whose extremities are blunt, obtufe, and present a sort of a round knob-for the contrary happens in fact:--that this error arises from confounding the property of filently drawing fire from the clouds, with that of exciting lightning, two things which are very different, as M. Le Roy abundantly proves, in this memoir :that the conductors being designed, by their form, to draw the fulminating matter from all the parts of the building on which they are erected, ought, for that reason, to be : pointed, and to be çaised to a certain height above the building :-and that, finally, should an explosion of lightning fall upon these conductors, its effects would be much less violent, than if it fell upon the others.

ANATOMY. MEMOIR I. Obfervations on the Situation of the Liver, in its

natural State, together with Remarks on the Manner of per· çeiving several of its Disorders by the Touch. By M.

PORTAL.

In order to acquire, by the touch, a certain knowledge of the disorders of the liver, it is necellary to ascertain, by a series of observations, iis situation, which differs according to the age and attitudes of the patient, and which is also modified by seves ral maladies, which do not immediately affect the gland itself, The liver is larger in the fætus than in children newly born. The stomach of the former, which was perpendicular, becomes gradually almost horizontal : the left lobe of the liver, when deprived of the blood, which was conveyed thither by the um. bilical vein, diminishes considerably in fize: M. Portal ob. ferves farther, that this is not the only change occasioned by the revolution, which takes place in the circulation of the blood at the period of birth : the pelvis affumes gradually another form, the lower extremities, which receive a greater quantity of blood, grow in length, and acquire a new degree of strength and confistence. The form of the bason in the foetus, and the finallness of the lower extremities, are favourable to delivery : the child in the first period of life, when its weakness will allow it nothing beyond a kind of reptile motion, is so constituted, as to go on hands and feet; but as soon as the legs acquire ftrength, fufficient to support the body in an erect posture, their

proportion, proportion, and that of the thighs change; and all these changes, which are the necessary confequences of a change of circulation, seem evidently to have been prepared and combined by the Author of Nature for the advantage of the human frame.

The growth of the liver is not proportionable to that of the other parts of the body. In persons who have arrived at a mature ago, it lies entirely concealed under the spurious or baftard ribs, when they are placed in a horizontal situation. When they are in a different or erect position, the liver becomes perceivable, and this is therefore the situation that must be preferred, as the most adapted to exhibit, to the touch, the true state of that gland.

The liver acquires a monstrous volume by the excessive use of food, as appears from the e::periments that have been made on animals. Stoppages, or obstructions in the lungs, change the fituation of the liver, which, in these circumstances, extends itself under the ribs; but we must not, according to Mr. Portal, conclude from hence, that the liver is attacked : this is an error, into which he acknowledges that he has sometimes fallen, but the dissection of bodies undeceived him.

The liver, says our Author, is not the only part of the body that changes its situation in different attitudes. M. PORTAL observes, that ihe anterior part of the bladder, in a man who hands upright, corresponds with the same parts of the abdomen, to which the bottom of the bladder corresponds in a man who lies in a horizontal posture. Tois remark may be of confiderable use and importance in medical praclice. Such is the result of M. PORTAL's memoir, to which we refer the Reader for farther details and illustrations, relative to this interesting object of anatomical investigation, which he will find here very amply and accurately described and considered. MEMOIR II. Concerning an extraordinary Pregnancy. By M.

HALLER. This memoir contains the history of a woman, who, after having discovered all the symptoms of pregnancy, which the reckoned from the beginning of the month of June 1763, fell into a state of infirmity and languor, in which all these sympto.ns totally disappeared. She recovered her health in the month of May 1764: and the exhibited no marks of weakness or indisposition until July 1772.--She died in August, that year, after a violent fever, which lasted seven days, and was accompanied with intense pains. On opening the body, a kind of sack or tumour was found, which communicated with the uterus by the ilium on the right, and a part of the os sacrum, This sack, which had within it the right tube and ovaria, contained a fætus of seven months, whole putrefaction had occafioned the death of the woman ; however, the circumftantial

account account which is here given of her disorder and pregnancy, proves evidently, that the feetus had been without life from the month of January 1764. Notwithstanding this, the woman enjoyed a perfect state of health during eight years, with this lifeless mals in her body, and barrenners seemed to be the only effect it produced in the animal economy. M. HALLER mentions it as a circumstance worthy of notice, that after having suffered pains that seemed to indicate a miscarriage, in January 1764, which may be considered as the time of the death of the fætus ; the woman suffered again pains of a like nature, at the period which, according to the proper calculations, would have brought on the delivery; he observes farther, that at this period she had milk, which was, indeed, soon disa sipated, but returned two months after. MEMOIR III. Concerning a new Method of performing the Am.

putation of the Extremities. By M. PORTAL. · This memoir is designed to prevent the inconveniencies that arise frequently from the ordinary method of amputation, after which a part of the bone still remains jutting out. This not only renders often a new operation necessary, but also makes the cure difficult, exposes to dangerous accidents, and even after the cure is finished, prevents the stump from being covered with felh, which is attended with several disagreeable circumstances. We shall not enter into a particular analysis of this memoir, which might be obscure without the aisistance of the cuts that accompany it. We shall only mention the fact upon which M. Portal founds his new method, and shew, in a few words, in what this method essentially consists. The fact is, that the soft parts of the human body are almost all susceptible of contraction, after being cut; and this, though in a smaller degree, is observable, even in dead bodies. This contraction, or rather contractibility, is different in different parts of the human frame: it is strong and intense in the skin, the adipose membrane, the tendons, the aponeuroses of muscles, in the veins and arteries ; and its most powerful effect is produced in the moment of the feparation of the parts, though even after this feparation, it remains in activity for a confidera. ble time. It must, consequently, happen after the amputation of a member, that the soft parts, fhrinking in, leave the bone uncovered; and that the different parts, suffering a greater or less contraction, the wound assumes a pyramidal form, which renders the dressing more embarrassing, and the cicatrization more difficult.

If therefore (to come to what M, PORTAL proposes) the muscle be cut in the moment of its greatest contraction, it will thrink less than if the amputation had been made at the time of its greatest dilatation or extension, and a more considerable part

of

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