Page images
PDF
EPUB

differtations by the Abbé Bofcovick, on a method of determining the orbit of a comet ;-a method proposed by the Abbé Pezenas, of afcertaining the precife time of the fun's revolution, and the position of his axis, by means of three obfervations of a solar spot ;-fome obfervations of the tranfit of Venus in 1761-together with feveral other particular obfervations of eclipfes, &c.

In a fhort memoir, M. Bourrand demonftrates the quadrature of a certain portion of a circle, of a fimilar kind with the lunula of Hippocrates and in two other memoirs, M. de la Place treats of recurrent and recurro-recurrent feries; which he afterwards applies to the doctrine of chances.

MISCELLANEOUS ARTICLES.

Obfervations on the Method of grinding and polishing the Object Glaffes of Telescopes; by M. Antheaulme.

The theory of the achromatic telescope has been carried to fo great a degree of perfection, that little now remains but to improve the art of forming lenfes precifely to the figures required by the geometrician. It is certain however that this art has been far from keeping pace with the improvements in theory; and there is even reafon perhaps to regret that Cam pani, an artist of the last century, is not in being, to realise the new formula of the fpeculative optician t. This memoir contains fome practical obfervations on this art, derived from the Author's experience; by an attention to which, he believes that glaffes may be formed as accurately figured as those that came out of the hands of that celebrated optician.

C.

One neceffary circumstance, and of which we took notice in the article above referred to, is a fcrupulous attention to the fineness and even nefs of the paper, with which the bafons fhould be lined on which the lenfes are to be polifhed, after they have received the proper figure. But the moft material obfervation made by the Author relates to the change of figure, which he has found that an accurately formed lens, particularly one of a long focus, undergoes, in confequence of the particular kind of motion given to it in the polifhing. The lens is polifhed, it feems, by pushing it forwards, or from the operator, in a strait line. The confequence is, that the hinder part of the glass undergoes a greater degree of preffure, and confequently more friction, than the fore-part: and as the workmen generally keep turning the lens round, during the operation, it neceffarily acquires a conical figure, as he has experienced.

+ Some anecdotes relative to the manœuvres of Campani, by which he acquired fo high a degree of reputation in his art, may be feen in our xlth volume, June 1769, p. 500.

APP. Rev. Vol. li.

The

The Author is of opinion, that Campani's principal fecret confifted in an attention to this feemingly minute but importanc circumstance; and that he polished his lenfes by giving them the fame rotatory motion round the bason, that was used in the grinding them. He was led to this obfervation, by having had the figure of an object lens, intended for an achromatic telescope, altered by polishing it in the common manner: and the justice of his fufpicions, concerning the cause of this alteration, was confirmed by his fuccefs in restoring the lens to a perfect figure, on his polishing it with a circular motion ;— a practice which, he fuppofes, the workmen have been tempted to neglect, on a fuppofition that the change was of no confequence, and because the prefent method is more easy and expeditious.

We fhall not dwell particularly on the contents of three memoirs written by M. du Tour; two of which are the fequels of articles begun in the former volumes of this collection. In one of them, the Author treats of the cause of fquinting. The fubject of the fecond is the inflection of the rays of light, in their paffage near bodies; the cause of which the Author attributes to certain atmospheres furrounding bodies, and the refractive power of which he supposes to be less than that of the ambient medium, or the air. On this hypothesis he explains the various phenomena relative to this fubject, observed by Sir Ifaac Newton, Dr. Jurin, and others. In the third, he endeavours to establish the truth of the principle, that each visible point of an object is feen in the direction of a ray proceeding from that point to the eye.

In the last article of this collection, according to our arrangement of the memoirs, are contained fome ingenious obfervations, by M. D'Antic, on the manufacture of delft-ware; which feem to be founded on the principles of chemistry, and a practical knowledge of the art.

ART. IX.

Vermium Terreftrium & Fluviatilium, &c. Succin&a Hiftoria, &c.— A fuccinct Hiftory of Animalcules, Worms, and testaceous Animals, not Inhabitants of the Sea. By Otho Frederick Müller, Correfpondent of the Royal Academy of Sciences, &c. 4to. 2 Vols. Leipfic, &c. 1774.

L'executed

numerous N this performance the learned and induftrious Author has executed the difficult task of arranging all the numerous fubjects of the animalcular kingdom, under different genera, and of defcribing each diftinct fpecies; fo as to form this new branch of zoology into a regular fyftem. He next proceeds to clafs and defcribe, in a fimilar manner, all thofe other animals,

which, together with the animalcules above mentioned, he comprehends under the general denomination of Vermes: including in that term, not only worms, properly fo called, leaches, polypes, &c. ; but likewife teftaceous animals, fnails, &c. In our next number we propose to give a fuller account of the plan and contents of this work.

ART. X.

Hiftoire et Memoires, &c.-The Hiftory and Memoirs of the Society formed at Amfterdam, for the Recovery of Persons that have been drowned. Vol. II. Part I. 8vo. Amfterdam. 1774.

T

HIS fecond volume of the hiftory of the Amfterdam fociety, contains fifty-eight cafes of drowned persons, reputed dead, who had been restored to life, through the means indicated by this benevolent affociation.

The most remarkable of these hiftories is the 36th, in which is related the cafe of a person, who, in the middle of January, and in a state of drunkenness, fell into the water, from which it appears that he was not taken out, till an hour and a quarter after the accident. All his limbs and joints were become rigid and inflexible; fo that his arm could not, without great violence, be detached from the fide of his body, to which it was, fixed, when the furgeon first attempted to bleed him. In confequence of the zeal and perfeverance of the affiftants, fome faint appearances of life were perceived in about two hours; and by continuing their efforts near two hours longer, the patient was fo far recovered, as to be in a capacity to walk home.

The prefent volume contains likewife an abridged account of the regulations lately made at Parist, and in other places, relative to this object; and of the fuccefs which has attended the execution of them in the above mentioned city. From this abstract it appears that, in the space of nine months, twentythree drowned perfons had been recovered; one of whom had been above three quarters of an hour under water.

See the Appendixes to our 45th and 47th volumes.

+ See a detail of the Succefs of the Parisian Society, Review, Feb. 1774, P. 150.

AR T. XI.

Cinquieme Lettre à Monfieur de Voltaire, &c.

Par M. Clement.- Cle

ment's fifth Letter, &c. to Voltaire. 8vo. Paris. 1774.

IN

N our laft Appendix we gave an account of M. Clement's fourth Letter to Voltaire; we have now the fifth and fixth before us. They are written in a manner no less sprightly and entertaining than the preceding, and do no less honour to the Author's taste and judgment: it is only to be regretted, that the defence of Corneille, which is the fubject of both the present

Oo 2

prefent Letters, is abundantly too long. The fifth Letter con tains 237 pages, and the fixth no less than 360: this is enough to try the patience of every Reader, and there are few, we apprehend, even of those who are the greatest enemies to Voltaire, that will have a fufficient share of fortitude and resolution to carry them through fuch a length of criticifm. Those who have, however, will find frequent occafion of applauding the Author's tafte, and the fpirit wherewith he defends a writer of fuch diftinguished merit as the great CORNEILLE. M. Cle ment appears to have carefully ftudied Corneille's writings, and in the letters now before us, he has pointed out, and very happily illuftrated, fome of the principal beauties of his best dramatic pieces. His zeal, indeed, for his Author's fame, and his indignation against M. Voltaire, have sometimes, it must be acknowledged, carried him too far, and drawn fome remarks from him that are unworthy of a candid and libéral critic. This, however, happens but feldom, and those who are converfant with Voltaire's writings, and have obferved the malignant and illiberal manner in which he frequently attacks the reputation of the most eminent writers, and of Corneille in particular, will readily apologize for him, and make fome allowances for a young and fprightly writer, who generously steps forth in defence of one of the greatest geniufes France can boast, against the greatest wit and most fashionable writer of the present times.

Voltaire, it is true, frequently commends Corneille, and fometimes expreffes his admiration of his genius in very strong terms; but, as M. Clement very justly obferves, he is, in general, very referved and temperate in his commendations. It is eafy, indeed, to obferve an air of envy and jealousy in the whole of his commentary: but we must refer our Readers to M. Clement's letters, where they will fee Voltaire's artful and infidious management in order to hurt Corneille's reputation fairly expofed, and placed in a clear and ftriking light.

The cenfures which Voltaire has pailed upon those great writers of the last age, whom our Author has defended in his preceding letters, were, as he obferves, only occafional, hafar dies en paffant, jettées à l'aventure; but with regard to Corneille, fays M. Clement to Voltaire, c'est un corps d'ouvrage que vous élevez contre les ouvrages de Corneille. Vous vous êtes attaché à lui pour le miner fourdement, comme la rouille s'attache à l'acier pour le ronger. Il est donc à propos de mettre plus de fuite et de travail dans cette réfutation que dans les autres. Je redoublerai mes efforts, pour n'être pas au-deffous de la caufe que j'embraffe. Je combats pour le plus grand Génie du dernier fiécle, contre le plus Bel-efprit du

nôtre.

Such are the reasons which our Author affigns for his long and elaborate defence of Corneille, and our Readers will allow them

[ocr errors][merged small][merged small]

them what weight they think fit.It may not be improper to acquaint them, before we conclude this article, that M. de Voltaire has given the public a new and beautiful edition of Corneille's works, with many additional notes, in eight volumes,

quarto.

ART. XII.

Epiftolarum ab Eruditis Viris ad Alb. Hallerum fcriptarum, Pars I. Latina. Vol. I. II.-Letters from Men of Learning to Haller. 8vo. 2 Vols. Bern.

I

N this collection, which contains about four hundred letters, fuch of our Readers as are fond of the ftudies of botany, anatomy, medicine, &c. will find both entertainment and inftruction. It likewife contains fome interefting particulars which relate merely to literary hiftory, and the characters of eminent writers; but what there is of this fort, lies within a narrow compass. As in almost every collection of this kind, fo in the prefent, there are many trifling letters, which can be of no ufe, unless it be to fwell the fize of the work, and fill the pockets of the book feller.

There are no letters in the collection from Haller in answer to those received from his friends and correfpondents, for he tells us in the preface to his firft volume, that he kept no copies of his letters.

The principal writers of the letters now before us are these following:-Albinus, J. Gefnerus, J. Fred. Schreiber, Chrift. Fred. Hanel, T. Georgius Gmelin, J. Jacobus Scheuchzer, Carol. Linnæus, J. Jac. Dillenius, Nic. Rofen, Eberhard Rofen, Chrift. Gottlieb Ludwig, Paul Henr. Gerard Mochring, J. Philip. Burggrav, Emanuel Koenig, &c. &c.

Thefe Latin letters, we are told, are to be followed by others, in French, German, English, and Italian.

ART. XIII.

Bibliotheca Anatomica. Qua Scripta ad Anatomen et Phyfiologiam, facientia a rerum initiis recenfentur. Auctore Alberto Van Haller, Sc. -Haller's Anatomical Library, &c. 4to. Vol. I. 1774.

THIS

HIS is the third volume of Haller's Bibliotheca Medicina et Hiftoria Naturalis, and is a valuable and useful monument of the Author's extenfive knowledge and unwearied industry. He traces anatomy from its origin, through the several fteps of its progrefs, to the beginning of the prefent century; gives an account of the principal writers who have cultivated this useful fcience, and of the difcoveries and improvements they have severally made; pointing out, as he proceeds, the

See accounts of the first and fecond volumes, in our Appendixes to our xlv. and xlvi, volumes.

003

particular

« PreviousContinue »