.my efforts towards that end, I wait with confidence, I repofe on thy juftice, and resign myself to thy will.'

That numerous and refpectable clafs of Readers, who have been charmed with the writings of M. Rouffeau, will readily recognise his hand in this performance: at the fame time, they cannot fail to be hurt at various parts of it, which exhibit a mortifying and affecting picture of the weakneffes of human nature; and particularly of the extreme and even morbid fenfibility of this extraordinary man. The fubjects difcuffed in this dialogue are so involved, and would require fo much prefatory explanation, that we cannot give any fatisfactory fpecimens of it without transcribing several pages. Though the authenticity of the work is fufficiently afcertained by internal evidence; we fhall add, that the original manufcript, written fair with M. Rouffeau's own hand, has been depofited by the Editor in the British Museum.

ART. III.

Ed. Sandifort Obfervationes, &c.—A Collection of Anatomical and Pathological Obfervations; Books 2d and 3d. By Ed. Sandifort, Profeffor of Phyfic, Anatomy, and Surgery, in the University of Leyden. 4to. Leyden. 1778 and 1779.

T

HE nature of this publication is fuch as to require from us only a short and general account of its contents. The fecond book is divided into eight chapters, the greater part of which contain anatomical descriptions, and pathological remarks, relating to the uterus.

The Author having lately had an opportunity of diffecting the body of a woman big with child, who died before delivery, minutely describes, in the first chapter, all the appearances on diffection; adding a variety of obfervations refpecting the subject, made by the most accurate anatomifts and phyfiologifts. The defcription is illuftrated by several plates, fmall indeed, but well executed. In the fecond chapter he offers various obfervations, deduced from actual diffections, with regard to the oblique pofition of the uterus, occafioned by the unequal length of the liga ments; as well as other remarks refpecting the os uteri, and the occafional stoppage of the Fallopian tubes.

In the third chapter he treats principally of a human ovum, which had been expelled after about eleven weeks fupposed pregnancy; and which, though it appeared to be perfect in every other refpect, was found not to contain the least veftige of a foetus within it. Inftances are likewife given of the dege neracy of a placenta into hydatides. The fourth chapter contains an account of feveral varieties in the placenta and umbilical

chord.

hord. In the fifth, are related the fatal confequences enfuing the too hafty and violent extraction of the placenta. In the fixth, the Author defcribes certain anchylofes of the offa pubis; and in the seventh and eighth he treats of fome varieties in the number of different parts or organs of the body, and in the courfe of the lacteal veffels.

The third book is divided into ten chapters; in the first of which is given a very particular description, illuftrated, as are almost all of the Author's obfervations, by figures, of a foetus born alive; in which were prefented many remarkable conformations of various parts; particularly an immenfe umbilical rupture, in which were contained many of the vifcera of the abdomen. In the fecond chapter are contained accounts of the offification of the pia mater, and of other parts: and in the third is given the hiftory of a fatal fuppreffion of urine, in confequence of a stone sticking in the urethra; which was ruptured fo as to form two canals.

The fourth chapter prefents us with the cafe of a young lady, who had for two years had a tumour near the inner angle of the eye; which discharged matter, and caufed the tears to flow continually down the cheek. The Author attempting the cure of this diforder by incifion, difcovered the cause of this complaint, which he foon removed, by the extraction of a flone fomewhat bigger than a pea.

In the fifth chapter, an account is given of a remarkable thickness and hardness of the peritoneum; and of a concretion or cohesion of almost all the abdominal vifcera, in a body which he diffected. In this fubject he found the foramen ovale open; and obferves, that this circumftance exifts much oftener than is fufpected.

The fixth chapter contains fome new obfervations, confirming and illuftrating those which the Author had produced in the preceding book, relative to the human ovum. In the feventh is given a description of a fingular kidney; and in the eighth and ninth, various obfervations refpecting the futures of the bones of the cranium. The tenth and last contains descriptions of various bones, which differ from the ufual form. Befides the obfervations peculiar to the Author, he has collected many others relative to the fubjects here treated of, from the beft authors and the plates, which amount to eighteen in the two books, appear to be executed with equal accuracy and neatness.

ART.

on

ART. IV.

Collection de différens Traités, &c.-A Collection of feveral Treatifes Aftronomical Inftruments, and others, relative to various Branches of Experimental Philofophy, &c. With useful Tables, and Copper-plates. By J. H. de Magellan, F. R. S. Correfpondent Member of the Royal Academy of Sciences at Paris, &c. 4to. Paris and London. 12 s. Boards. White, Elmsley, &c. 1780.

HE Author of this Collection of ingenious tracts is equally

THE well known to the learned world by his extenfive corre

fpondence, and by the zeal and ability with which he himself profecutes philofophical inquiries. In the Appendix to our 56th volume, June 1777, page 548, we gave an account of a very useful work published by him, containing a particular defcription of the English octants and fectants, or, as they are commonly called, Hadley's quadrants; together with the defcription of a new fectant invented by himself. The present work is to be confidered as a fequel or a second part of that performance, and appears to have been compofed by the Author, principally in confequence of his having undertaken to fuperintend the conftruction of five capital collections of aftronomical and philofophical inftruments, executed by English artists for the court of Portugal; and foon afterwards of fix fimilar collections for the court of Spain. In these treatises the Author describes the various inftruments in the moft particular and fatisfactory manner, as conftructed under his inspection, by the first artists in London; giving a particular account of the various improvements they have lately received, many of which they owe to himself. Thefe defcriptions are illuftrated by several copperplates.

The firft of thefe tracts contains the defcription of a new circular reflecting inftrument, invented by the Author, for the purpose of obferving, with the greateft precifion, angular distances at fea and a method is likewise fhewn of altering the common fectants, fo as to obtain, in part, the fame advantages.

In the fecond tract, Mr. Magellan describes, in the most minute manner, the conftruction and method of using the improved portable aftronomical quadrants, which form a capital part of the above-mentioned collection; particularly with a view to the instruction of those, probably inexperienced, philo fophical travellers, and navigators, or young aftronomers, whose office it may be to make use of them. We should observe, that these Collections are evidently intended for the use of philofophical expeditions, probably in South America; and the different inftruments are accordingly difpofed in their respective cafes, in such a manner, that one complete collection is diftriAPP. REV. Vol, lxiii.

K k

buted

buted into fix cafes, nearly of equal weight, fo as to be conve niently carried by three horses.

In the next tract, Mr. Magellan defcribes very fully the conftruction and ufes of another part of this philofophical apparatus; we mean certain new portable barometers, adapted particularly to the measuring the height of mountains, and the depth of mines. In this part likewife the Author has contributed to the improvement of the inftrument; and has taken laudable pains to make the young obferver fully acquainted with every particular relative to the conftruction and manner of employing it; furnishing him likewife with various tables and examples, to render the practice of measuring heights familiar

to him.

Befides the barometers appropriated to this particular fervice, the Author defcribes various others adapted to common purpofes, and conftructed with a view of rendering the variations in the height of the mercury more fenfible. One of these was very lately invented by the Chevalier Landriani, of Milan, and is called the ftereometrical barometer; but the fhort description of it here given cannot be rendered intelligible without the figure. The fame obfervation may be applied to a new conftruction of a barometer propofed by the Author, under the title of the fectoral barometer; in which the fcale is magnified by the inclination of the tube, or its frame, which turns on an axis.

A third barometer which is here defcribed, called the ftatical barometer, is not new, indeed; for it was the invention of the Chevalier (we believe Sir Samuel) Moreland, who prefented one of them to Charles II. It is very extraordinary, Mr. Magellan obferves, that no authors who have written upon the subject of barometers, have, as far as he recollects, made any mention of this inftrument; nor has he feen more than two barometers of this kind, which he fuppofes to be the only two that exift in the world.- One of them was made in the year 1760, by the late Mr. Adams, for his prefent Majefty, then Prince of Wales. The conftruction of the other had been begun, perhaps fome time before, by the late Mr. Jonathan Siffon. found it by chance, well preferved, in a private house, and purchafed it; and I have it now by me, completely fitted up, having made fome changes that may be confidered as improvements in the conftruction.'

We cannot defcribe this curious inftrument without a plate: we fhall obferve, however, that it marks the variations in the heights of the mercury, by fpaces twice as large as those in the fimple barometer. We fhall mention, too, an obfervation of the Author's relating to it, who remarks, that the perpetual clock, or time-piece, which was conftructed in London fome

years

years ago, and which perfectly fucceeded, was formed on the fame principles with this ftatical barometer; the motions produced in the mercury, by the varying preffure of the atmosphere, being employed in renewing, from time to time, the power which gave motion to the pendulum.

This idea,' fays Mr. Magellan, is very happy :-but modern mechanism has very lately advanced much further, with respect to pocket-watches, which go continually, without the neceffity of ever winding them up :'-that office being performed by the motions neceffarily given to them by the person who wears them in his fob; and yet they are faid not to differ, either in form or fize, from common watches.- I have lately tried two,' he adds, made by Meffrs. Spencer and Parkins, during the space of twenty-eight days, and was perfectly fatif fied with their performance.'

Thefe obfervations are followed by a propofal of the Author's to conftruct a piece of mechanifm, which he calls a perpetual meteorograph, or an inftrument connected with a common timepiece, or eight-day clock, which fhall perform the office of a conftant and fedulous meteorological obferver, and indicate the weight, temperature, and moisture of the air, the force of the wind, the quantity of rain, the state of the tide, and other meteorological defiderata, during the abfence of the owner; as well as the precife hour, or even half hour, when the respective changes happened. The very ingenious ideas here thrown out by the Author, to facilitate the conftruction of an inftrument of this kind, and which, it appears, have in part been executed by him, can only be understood by having recourse to the performance itself; where we learn-with refpect to the barometer in particular-that a time-piece, which marks the motions of that inftrument, has been going for fifteen years paft, at Buckingham-houfe, made by Mr. Cummings; who has conftructed another of the fame kind, the price of which amounts to about 500 guineas;-and that the Author himself has executed a time-piece for the fame purpose, but on a different plan, which did not coft more than the fifteenth part of that sum, and which has been going for a year past.

The title of the next treatife is- An Effay on the new Theory of Elementary Fire, &c. with a Defcription of fome new Thermometers particularly adapted to the making of Obfervations on that Subject.' The Author appears to have written this effay with a view to explain to philofophers in general, as well as to his foreign philofophical correfpondents in particular, the principles on which Dr. Crawford grounded his late theory of animal heat;

* The Author here alludes, we fuppofe, to the inftrument exhibited at Mr. Cox's Museum.