These objections, and many others of no force in themselves, but in that age deemed irresistible, by reafon of the low state of human knowledge, prevented the Copernican fyftem from being generally confidered in any other light than as a mere hypothefis, and were the principal caufes of the celebrity for fome time maintained by the fyftem of T. Brahé." P. 124.

The fourth Chapter defcribes the fyftem of the celebrated Danish aftronomer Tycho Brahé, together with the methods he used for determining a variety of particulars in aftronomy. His fyftem has been long fince rejected as infufficient and erroneous; but the facts established by his numerous obfervations, which have enriched the fcience of aftronomy, will doubtless be acknowledged and remembered by the latest pofterity.

"The principal merit", this author observes, "of T. Brahé, and in which he far excelled all the preceding aftronomers of whom we have any knowledge, was that of a zealous, indefatigable, and moit ingenious obferver of the heavens; and, indeed, in the time in which he lived, this was the chief and molt important diftinction which an aftronomer could attain. He properly confidered obfervations as the only foundation of a juft aftronomy; and finding aftronomy as it then flood, in a great measure deftitute of this foundation, he extended them to the greatest part of the celeftial phenomena. Though he had to contrive and form the greatest part of his inftruments, he determined, without any affittance from the pendulum, and by the laborious method of diftances, the pofitions of no less than 777 fixed stars; the parallaxes, refractions, diameters, and whole peculiarities, of the fun, moon, planets, and even the comets which then appeared, were fubjected to his examination; and by the uncommon magnitude of his inftruments, and the ingenuity of their conftruction, he not only attained to an accuracy before unknown, but alfo made feveral perfectly new discoveries, ftill allowed to be of the most delicate and fubtle kind, and most apt to elude obfervation." P. 133.

The fifth Chapter commences with an account of Kepler's life. This ingenious and indefatigable man was born in the Dutchy of Wirtemberg, in the year 1571. He was the difciple of the aftronomer Maefllinus, and in the year 1591 was appointed Profeffor of Aftronomy at Gratz, in Stiria, which office, it is faid, he accepted with reluctance. Two years after this appointment, he publifhed his myfterium cofmographicum, as the first fruits of his aftronomical ftudies. Not long after, he became acquainted with T. Brahé, from whose obfervations Kepler's inveftigations of the theory of aftronomy derived no fmall advantage, and upon which, as a folid foundation, he inflituted a variety of calculations.

I

BRIT. CRIT. VOL. XXIV. AUGUST, 1804.

All

All thofe particulars are described at large, and with piopriety, in this fifth Chapter, together with all the intermediate Heps, and collateral circumftances.

A fimilar obfervation may be made with refpect to the contents of the fixth Chapter, which treats of Kepler's theory, founded on apparent oppofitions, and of its total failure.

In the feventh Chapter, which treats of Kepler's 'folar theory, this author relates, that Kepler began his researches from the second inequalities of the planets, and how he pursued the track with that remarkable peculiarity which diftinguished him from other men; namely, an unconquerable defire of dif covering the caufes of natural phænomena, and of tracing them up to general analogies and laws. His hypothefis of the action of the fun on the planets, of the paffive nature of the latter, of the fuppofed caufe of their variations, also the imperfections of thofe hypothefes, and the fubfequent, attempts to correct them, are likewife particularly defcribed in this Chapter.

The eighth, which is the longeft and the most interesting Chapter of the work, contains the application of the phyfical method of equations to the planet Mars, together with its im portant confequences.

Dr. S. defcribes niinutely and in regular order, the various attempts, the laborious calculations, and the difappointments, with which Kepler's invefligation of the theory of Mars was attended, together with the accidental circumftances which laftly crowned his labours.

The tranfition from the theory of Mars to those of the other planets was natural, and apparently lefs perplexing; yet it was not without a confiderable deal of labour and patient examination, that at laft Kepler fucceeded in eftablifhing his famous planetary laws; namely, that every planetary orbit is an ellipfe, in one of the foci of which the fun is fituated; and that in revolving round this common focus, every planet defcribes areas proportionate to the times of its motion. Alfo, that the fquares of the periodical revolutions of the planets are conftantly proportional to the cubes of their diftances from the fun.

Dr. Small defcribes, in a particular manner, all the fteps which led to the accomplishment of thofe difcoveries, together with the folutions of certain problems which depended

thereon.

Without the affiflance of diagrams, it would be impracticable for us to render the nature of those discoveries fufficiently intelligible to our readers; nor, indeed, could this be required at the present time; confidering that Kepler's discoveries, and

the

the most direct methods of calculating what belongs to the planets, are now generally underflood, and are defcribed in a variety of aftronomical works. Nevertheless, Dr. Small's work is entitled to much commendation. He has given, in plain but very intelligible language, a pleafing hiftorical review of the fyftems of aftronomy; has fhown how the errors and imperfections of one fyftem were inftrumental in the formation of another lefs exceptionable hypothefis; and has pointed out the very fteps by which a fucceffion of induftrious human beings have afcended from a ftate of the most abject ignorance, up to the knowledge of the fublimeft truths.

ART. IV. Medical Sketches of the Expedition to Egypt from India. By James M'Gregor, A. M. lately fuperintending Surgeon to the Indian Army in Egypt. 8vo. 7s. 238 pp. Murray. 1804,

THE medical officers attached to the Egyptian expedition, appear to have fulfilled the duties of their fituation with much zeal, and to have taken great pains to make themselves acquainted with the difeafes peculiar to that unhealthy climate. In fome of our late volumes, we gave an account of two publications on the difeafes of this part of Africa; namely, one by Mr. Dewar, and another by Mr. Powert; the latter on the endemic ophthalmia of that country; and the former on the various disorders which fhowed themfelves among the British forces, and particularly on the dyfentery; a complaint as frequent and fatal on the fhores of the Nile, as it is in the Weft-Indies. Mr. M'Gregor's observations on these disorders are not uninterefling; but having already given an account of these complaints from the before-mentioned authors, we shall pass them over in the prefent inftance, and proceed to notice this practitioner's remarks on the fever which appeared in that part of the army to which he was attached, and on the plague. The fever was of the remittent (and fometimes intermittent) type, and is reprefented to be the fame as the remittent fever of Bengal; the fame, in fact, with that which prevails over the peninfula of India and the eaftern iflands. The first step in the cure of it was to cleanfe the primæ viæ, by calomel and

* Brit. Crit. vol. xxii. p. 314.

+ Ditto, vol. xxi, p. 674.

I 2

neutral

neutral falts. Some gave emetics; but thefe, in this author's opinion, were not always neceffary. In the firft ftage, likewife, as particular fymptoms called for them, venefection was performed, and blifers were applied, with diaphoretics and opiates; but if the fever was of any duration, the conftant practice was to endeavour to affect the mouth as fpeedily as poffible with mercury. On the fubject of fever, the author adds, that no well marked cafe of typhus occurred in Egypt, and that he never faw a cafe of this fort of fever in India, the climate of which appears to be inimical to it.

We now proceed to the most important part of this publication; we mean the obfervations on the plague.

"There is an opinion which very generally prevails", the author obferves, in regard to the plague; namely, that extremes of both heat and cold ftop the progrefs of the contagion. If this be true in regard to heat, it did not appear to be fo in the army in Egypt, in regard to cold. It raged moft in the coldeft months. In different countries, and in different feafons in the fame countries, the plague affumes very different appearances. Our knowledge of this fact enables us to reconcile the oppofite accounts given of the difeafe and of its treatment, by different writers. In the Indian army, when the disease first broke out, the cafes fent from the crowded hofpitals of the 61ft and 88th regiments, were, from the commencement, attended with the typhoid or low fymptoms; while the cafes fent from other corps encamped near the marthy ground of El Hammed, were all of the intermittent or remittent type. The cafes which occurred in the cold rainy months of December and January, had much of the inflammatory diathefis; and Mr. A. Whyie remarked, that every cafe admitted into the hofpital at Rhamania, had fymptoms of pneumonia. At the end of the feafon, it wore the form of a mild continued fever."

The author feems to have no doubt refpecting the contagious nature of the plague, but he thinks it communicable only by contact. Then follow hiflories of feveral cafes (among which is that of Dr. Whyte, who tried the rafh experiment of inoculating himfelf with the matter of a peftilential bubo, and died feven days afterwards) illuftrative of the fymptoms and treatment of this diforder. The fymptoms are fo fully detailed by various writers, that it cannot be neceffary to particularize them here; but it is proper to infert the author's remarks concerning the treatinent.

"A variety of modes were put in practice; but with fo little advantage, that fome were inclined to defpair of fuccefs from any. Though with it, many were loft; yet oxygenation, and particularly the ufe of mercury, had moft fuccefs. The first indication was to clear the prinæ viæ. Some gave emetics; but, in general, there was no time for this. The general practice at last was, to begin with a purge of calomel, which, if it operated brifkly, relieved the head,

and

and rendered the skin foft. The fecond indication was to induce a ptyalism and perfpiration. As offering the faireft profpect of effecting both at once, Mr. Price proposed the warm nitric acid bath; but the flock of nitric-acid was infufficient for this, otherwife than on a fmall fcale. Nitric acid was given internally; and where the patients would, drink it, it fhowed good effects. Mr. Price thought well of the citric acid. In fome of the Arabs he effected cures by this, and by a bath of ftrong vinegar. Others wathed and fpunged their pa tients with vinegar or lime juice. The third indicion was to obviate debility. With this view, bark, wine, and opium, were very largely given; and, at a certain ftage, the cold-bath. Dr. Whyte ufed the lancet very freely, but every one of his patients died. Some gentlemen attached to the Brunonian fyftem, put the ftimulating plan to the teft, keeping their patients under the influence of wine and opium; but this practice was never fuccefsful, and they deferted it."

On the whole, the author feems to be perfuaded that mercury and the nitric acid are the beft remedies against the plague; but he inculcates, that they must be very early and very liberally exhibited. When the ftomach becomes irritable, he fufpects they can never be given with propriety. He regrets that a fair trial was not given to cold-bathing. veral places the author hints at a fimilarity between the plague and the yellow fever; and, at the end of the volume, the points of the refemblance are exhibited in the form of a table.

In fe

Contrary to what has proved to be the fact with regard to its operation in this country, Mr. M'Gregor flates that the nitric acid was fuccefsfully adminiftered to fyphilitic patients in Egypt, as well as in India. The difeafe is doubtlefs much milder in thefe climates than it is in Europe.

But, to return to the fubject of the plague, we would remark, that the employment of acids in this diforder is a very ancient practice; and that it is by no means proved, that the nitric acid is fuperior to the acid of lemons or even vinegar, as an antipeftilential medicine: and though upon further trial (and further trial is certainly wanted) it fhould be found that calomel, and other preparations of mercury, have a decidedly remedial effect in cafes of the plague; it by no means follows, that this effect is to be afcribed to oxygenation, fince the mercurial oxyds have an action upon the living body diftin&t from, and vaftly more powerful, than that which is dependent upon the quantity of oxygen they contain.

ART.