quently the place where cold tumours are found. Our Author describes with precifion and perfpicuity the manner in which the inflammatory tumour is formed and increased, proves that the nerves have another property not lefs effential and diftinctive than their fenfibility, and lays down a theory for the cure of this disorder, which he confirms by experimental proofs of the falutary effects of his medical precepts.-This is followed by a curious difcuffion concerning fuppuration, and pus, in which the Author unfolds points of view, that may be useful in practice, and that are new to us. He diftinguishes pus into two kinds, the one corrofive, and the other he is inclined to call nutritive. This laft is produced from the nutritive part of the ferum, which divides and precipitates itself like a fediment, when it is in a ftate of ftagnation, and begins to be loaded with a collection of putrid matter.-One of the good confequences of this difquifition is, that it will fometimes prevent our being alarmed, when we fee a confiderable quantity of pus or purulent matter iffuing from the lungs, the uterus, the vagina, the ureters, fince this may happen, says our Author, without any confiderable damage, nay fometimes without any damage at all, to thefe parts. An irritation of the nerves, a weakness in the membranous fubftance of these parts, is fufficient to occafion a separation of the ferous viscous humour that is defigned to consolidate their furface, and from thence refults the evacuation of pus here mentioned. The method of curing this indifpofition furnishes our Author with an occafion of communicating feveral useful obfervations.

The third Differtation (the fubject of which is the Dropfy) contains a method of curing that diforder, when lodged in the peritonæum by a chirurgical operation, which is attended with no difficulty and little danger. This operation confists in an incifion of three or four fingers breadth made in the membrane which contains the vitiated matter; and this incision must be kept open during the whole time of the cure, both that the entire evacuation of the matter may not be prevented, and that the membrane may be cleanfed by proper injections. The falutary effects of this method of cure are abundantly afcertained by unanswerable arguments, that is, by facts. Of twenty-eight perfons, fays he, who underwent the paracentefis, or tapping, for a dropfy in the peritonæum, not one escaped; whereas of eight, who fubmitted to the operation already mentioned, only two died, on whom it had not been made with the proper precau

tions.

The remaining parts of this differtation exhibit to us reflections on the incifions that may be made in the breast for the cure of pectoral dropfies,-on the paracentefis in the pericardium, when the dropfical complaint attacks that part,-on the incifions

Nn 3

that

that may be made in the polypous excrefcences that are formed in the abdomen by a collection of extravafated boor, on the Cæfarian operation, and others of a fimilar nature, and on the diffolving power of the air, confidered in the effects may produce in the cure of feveral wounds, ulcers, &c.— pain the whole, thefe differtations have an undoubted tide to the attention of the Medical Reader.

AR T. IX.

Bemerkungen aber einige gegenden des Kathalien Dest, Chants, Ee. -Obfervations on fome Parts of Germany, in the Roman Cachotic Provinces, made during a Literary Excurion- sich are fibjoined Six Letters of the celebrated LEIBNITZ, wikh are now published for the frå Time. 8vo. Naremberg. i.

TH

HESE obfervations of three Proteffant travellers are neither uninftructive nor unentertaining; yet they would not have drawn our attention, had not the inmorti of Leibnitz food in the title page. The great cbject of thefe travellers feems to have been a vifit to the university of Angolttadt in Bavaria, of which the Prince-Bishop of Eich-fact is Chancellor, and their expectations appear to have been fully answered. They met with a remarkable fpirit of toleration and charity among the protettors of theology in that univertity; where they found natural philofophy, mathematics and aftronomy, in a pretty good fate, under the inspection, principally, of the exJeluit Helfenzrieder, who is eminent for his knowledge of these iciences.-This learned man has acquired a contiderable reputa tion by a fire-pump and telescope of his own invention, and feveral other improvements in natural philofophy; and he is seconded in his zeal for the advancement of the iciences by Profetor Giber, whole item of phytics, of which the two firft parts are already published, is highly effeemed. The latter made feveral experiments to enterta a cur travellers; among others, he communicated the magnetic power to a bar of iron, merely by ftriking it with a wooden hammer, and drew electrical fparks and a crackling nove from a piece of dry paste-board, by rubbing it with the fin of a cit.

We that not follow our travellers any farther, but terminate this article by an account of the fix letters of the famous Leibnitz to Fazer Orban. To's learned Jet was confeffor to the Elector of Bavaria; be acorned the college of his fociety, in the univerity of Ingolfitude, with rica ecuations in medals, manufampts, pictures, macales, books, antiquities, Chinese dredes, furniture, and curicaties. The Profetor Gabler permitted our travel ers to copy the letters that Leibnitz wrote to suis learned fellit, and even coultated to their publication.

In the first of these letters, dated 1705, Leibnitz communicates to Father Orban his binary arithmetic, wherein all numbers are expressed by 1 and o, and by which the mystery of the characters of Fobi, the ancient king and philofopher of China, may be easily explained. Father Bouvet, a miffionary in that empire, who alfo correfponded with Leibnitz, availed himfelf of this discovery to explain to the Chinese literati the poffibility of a creation from nothing, and to engage them to receive that doctrine.

In the fecond letter, which is dated in 1712, and treats particularly concerning burning glaffes, we learn that a mechanist had brought to Berlin a concave mirrour made of wood, and covered or lined with leaves of polifhed gold, which reduced metals to fufion in a little time, and which might be employed to light a candle in the fame apartment by placing in its focus a burning coal, and blowing it briskly.

In the third letter, which bears the fame date with the preceding, the German philofopher appears in another_point of view. At the recommendation of one of the Dukes of Brunswic (Anthony Ulric), he had obtained from the Emperor the dignity of Imperial Aulic Counsellor; but he confefles to Father Orban, that this bare title without any appointments was to him a matter of indifference; and he folicits the Jefuit to employ his credit, if not with the Emperor, at leaft with his confeffor, to render this honour profitable. The terms, in which this folicitation is expreffed do little honour to Leibnitz. He defiresFather Orban, to write a lettter which may be fhewn to the Emperor, and may let him know, that he, Leibnitz, is the friend of Father Orban, and of the fociety (the company of Jefus), that he is esteemed by Cardinal Ptolomei, that he had been high in favour with the late Queen of Pruffia, and was ftill on the fame footing with the Princefs her mother; that the Elector of Hanover, and the King of Pruffia, not only employed him as a man of letters, but also as a man of business, and that he might be of great ufe to his Imperial Majefty with refpect to the administration of juftice, the improvement of hiftorical knowledge, and the advancement of the fciences. All this was true, but it was little.

In the fourth letter he offers Father Orban, for the Elector Palatine, a complete copy of the Florentine edicts or diplomas, by which it appears, that the Emperor Charles V. out of his mere favour and Imperial authority, placed Alexander and Cofmo de Medicis at the head of the Republic of Florence, and extended that grant to all their male descendants; and that the Emperor always treated the Florentines as fubjects of the empire. The two following letters, dated in the years 1715 and 1716, are relative to the political affairs of the times.

ART.

X.

Oeuvres Complettes de M. Le Febure, &c.-The whole Works of M. Le FEBURE, Major of the Corps of Engineers of Pruffia, and Ordinary Member of the Royal Academy of Berlin. 2 Vols. 4to. Enriched with a great Number of Copper-plates. Maefticht and Boullion. 1778.

THI

HIS publication contains a treasure of theoretical and practical science for thofe neceffary plagues in human fociety, the licensed flaughterers of their fellow-creatures. M. Le FEBURE is a learned, ingenious, and experienced officer: and as we have not a great number of books of merit upon the fubjects that are treated in these volumes, they will be undoubtedly an acceptable present to the public, at a time when attack and defence are likely to be carried on with vigour.

A Treatise on the Attack and Defence of Places takes up the first volume of the work before us. It is divided into two parts: in the firft our Author defcribes all the operations of the befiegers and the befieged, day by day, from the investing of an ordinary fortified town to its furrender, and confirms all he fays on this complicated fubject by examples taken from the war of 1741. In the fecond he treats fucceffively of all the particular works of fortification that are to be met with in the ftrongest places and the moft complete fyftems, and fhews the beft manner of attacking and defending them. To his dreadful inftructions on this fubject, he has fubjoined the trials of Belidor's globe of compreffion, one of which was made at Potsdam in 1754, in the prefence of the king of Pruffia. It is from that monarch's letter of congratulation to the inventor, that our Author has taken a part of this interesting relation..

After fhewing the refpective advantages and defects, that are difcernible in the different works of a strong place, M. Le FEBURE proposes fome new methods of fortification, which do honour to his fagacity and knowledge in his profeffion; and he concludes his first volume by a very curious account of the operations of the Pruffian army in the attack of Schweidnitz in the year 1762, at which he was prefent. He acknowledges, with candour, the faults the Pruffians committed in that fiege, which continued above two months, though an hundred pieces of battering cannon were daily mounted against the town.Nothing is wanting to render this relation complete; and nothing can be more accurate than the numerous plans that are given to i luftrate it.

The fecond volume contains a Treatife concerning Mines,feveral pieces and letters relative to the trials of the globe of compreffion,-A new Treatife on Levelling, dedicated to the king of Pruffia, and accompanied with feven plates,-An Essay on the Manner of compofing Topographical Charts, to which are fubjoined

two

two maps compofed on the principles of M. Le Febure, the one reprefenting the Eastern part of North-America, and the other the courfe of the river of St. Lawrence, both bearing date in the year 1762.

There are notes interspersed in feveral parts of these volumes, and these notes contain, almost always, acute obfervations or curious anecdotes.-In one of these he obferves, that the French, though they are furnished with good engineers, and have acquired reputation by their fieges, are nevertheless remarkable for their blunders in reconnoitring the works of fortified towns. In 1745, at the fiege of Oftend, they did not difcern the fort La Plume until the balls from it were pelting them in their trenches; this fort was not even marked in their plan. But the anecdote relating to Lowendhal at the fiege of Bergen-op-zoom is ftill more curious, and we fhall give it in our Author's own words. • When this general, fays he, went, at the head of the principal officers of the artillery, to reconnoitre Bergen-op-zoom, they all thought that they perceived diftinctly formidable horn-works, juft fuch as were drawn or engraven in their plans of the place. While they were in this illufion, I was bufied in effacing these horn-works in my plan, with a perfon (N. B.) who held a confiderable rank in the city, and had left it fome days before. This man began by telling me (M. Le Febure was then in the French service), that the fortification of the town had been conftructed upon a plan entirely new at the beginning of the prefent century.I drew, in confequence of his information, a new plan, in which all the works were exhibited circumftantially, and fpecified with all the précifion poffible at such a time. order to be ftill more fully affured of the truth of the information I had received from this man, I went with my plan as near the town as was poffible, and perceived by the obfervation of feveral parts of the works the truth of what he had told me. I then presented my plan to Count Lowendhal, who began by looking for the horn-works, which they had perceived in the morning, and not finding it, afked me the reafon of this omiffion. I ventured to tell them they had been mistaken, and that there was no horn-work among the fortifications of the town. They told me, that in the ride they had taken, in order to reconnoitre the place, they had perceived diftinctly a horn-work near the Antwerp gate. I began to reply, when Count Lowendhal stopped my mouth by faying in a high tone, Well, well, fir, whatever it be, be it a toad, or be it a frog, it must spring.It was not until the day after, at the opening of the trenches, that they difcovered their error.'

But in

Some of the treatises contained in these volumes have been before published, but were become extremely scarce. They

are

4