pocrate Batavo condifcipulus, mihi olim religiofiffime adfeve ravit, lanceolam et nitrum, in regionum illarum paluftrium intermittentibus, fingula perficere atque abfolvere.'

The next fubject of his attention is, the Fluor Albus; and our author, among other prefcriptions, thinks it highly ferviceable, in this complaint, to breakfast on old Cheshire cheese and London porter. The following obfervations relate to the Fluxus Menftruus; Hemorrhage; Hemorrhoids Dropfy, and, on this fubject, we find fome valuable obfervations; Madness; the ufe of Milk; Lippitudo, cured by fmoaking; Lues, Venerea; Worms, the remedy principally recommended is the Pulvis Stanni; Meafles; Paronychia; Pulp of Colocynth, or rather fome difagreeable confequences, from, probably, too large a Dofe of the Remedy; Rhubarb; Rheumatism; the Influenza of 1782; Neutral Salts, in which the author attempts, we think unfuccefsfully, to establish a difference in their action, as purgatives; Bleeding; Sleep; Small Pox; Acid in the Stomach; Blifters, which, in acute difeafes of the lungs, the author thinks may be applied with advantage to the ancles, agreeably to Hippocrates' obfervation, that, in thefe difeafes, tumours on the calves of the legs are ferviceable; Ointments; and Wounds.

It will be obvious, from the variety of fubjects, we can give little account of each, unless our article was extended to the fize of the work. Our readers, from the fpecimen already felected, will have anticipated our obfervation, that the language is elegant, but fometimes laboured with too much care, and, in a few inftances, tortured into obfcurity. On the whole however, the attentive practitioner will find feveral valuable hints occafionally interfperfed. As we have transcribed a part which relates to medicine, we fhall conclude the article with an unexpected recovery from a defperate wound.

• Georgius Oylett tertiæ cohortis prætorianæ miles, dum fæ deratorum exercitus anno M, DCC, XLVII ad Brabantiæ vicum Nefleroi caftra haberet, in abdomine graviter acinace vulneratus erat. Interpofita femihora, inveni eum magnam inteftinorum partem, ne penitus evolverentur, cavo galero fuffulcientem. Valde illa inЯata, omentumque pulvere confperfum; ante quod difciffum, in fedes fuas inteftina nullo modo condere potui, tametfi per fe late patebat plaga. Ex cibo et potu, qui bus fe paulo ante liberaliter invitaverat, venuftiffima fane vaforum lacteorum facies per mefenterium difperforum. Repofitis omnibus, quum fanguis fatis multus ex omenti arteriis adhuc flueret, acu prælonga futuram feci interruptam dictam ; id quod ægerrime fiebat, propter fponte fe retrahens peritonæum, et ipfam mufculorum abdominalium craffitudinem. Fomentis adhibitis, oviumque recens cefarum pellibus hominem in dies bvolvendo, in integrum is reftitutus eft." 5

History

History and Practice of Acroftation. By Tiberius Cavallo, F. R. 8. 8vo. 65. in Boards. Dilly.

SINCE aeroftation continues to be fashionable, an abstract of the different voyages, and the means of repeating the experiment, with fuccefs, will be generally interesting: Mr. Cavallo has rendered it alfo very entertaining. The hiftory of the attempts to fly, previous to the fire-balloon of Montgolfier, is a pleafing performance; and it will gratify the vanity of the French philofophers, to perceive how desperate the fuccefs once feemed to be. Mr. Cavallo and Dr. Black indeed conteft, with justice, the priority of invention of airballoons; but the credit of Meffrs. Charles and Roberts is fcarcely diminished by these claims, for they feem not to have heard of the English experiments on this fubject, and were led to employ inflammable air, merely from fufpecting, that Montgolfier's balloon was raifed by the affiftance of a peculiar gas, from the burning ftraw. It would be unjust not to felect Dr. Black's very modeft and intelligent letter to Dr. James Lind.

"Dear Sir,

"The perfon who firft difcovered with exa&nefs the fpecific gravity of inflammable air, was, fo far as I kn w, Mr. Caven difh I never heard of any experiments made with that intention, before his appeared in the Philofophical Tranfactions for the year 1766. It had been my conftant practice before, to fhew, every year, in what manner it burns when pure and un'mixed with air, and how it explodes when air is mixed with it before it is fired; but Mr. Cavendish made a variety of fuch mixtures by rule and measure, and defcribes in the fame paper the manner in which they feverally explode. As foon as I read the above paper, it occurred to me, as an obvious confequence of Mr. Cavendish's difcovery, that if a fufficiently thin and light bladder were filled with inflammable air, the bladder, and air in it, would neceflarily form a nafs lighter than the fame bulk of atmospheric air, and which would rife in it;' this I mentioned to fome of my friends, and in my lectures, the next time I had occafion to fpeak of inflammable air, which was either in the year 1767 or 1768; and, as I thought it would be an amufing experiment for the ftudents, I applied to Dr. Monro's diffector, to prepare for me the allantois of a calfa The allantois was prepared, but not until after fome time had paffed, and when I was engaged with another part of my course, and did not choose to interrupt the bufincfs then going on; fo I dropped the experiment for that year, and in the fubfequent years I only mentioned the thing as an obvious and felf-evident confequence of Mr. Cavendish's difcovery; but finding generally fome difficulty in providing an allantois at the proper

time, I never made the experiment, which I confidered as merely amufing. About two months ago I was informed, by a gentleman in the fouth of Ireland, that he had tried it, and that it fucceeds perfectly well.".

In the remarks on Lunardi's and Blanchard's experiments, Mr. Cavallo agrees with thofe which we have given. He however is more fanguine in his expectations of being able to direct these machines; but, notwithstanding the fuccefs of meffieurs Roberts and Mr. Hullin, we think its attainment improbable. The hiftory of aeroftation, (perhaps from the rules of etymology it fhould be aeroftatation or aeroftatition, a græco fonte, parce detorta *) is not yet of great importance. The feveral adventurers feem to have afcended and returned full of wonder, and to have raised universal admiration, though no one experiment has been hitherto made, which inclines us to lock up with refpect to this new science. The voyage above referred to is chiefly interefting from the effects of the oars, in impelling the balloon: we shall tranfcribe the obfervations.

"We perceived below us fome clouds, that ran very rapidly

from fouth to north. We defcended to the level of those clouds, in order to follow that current, the direction of which was changed fince our departure. The clofe of day-light being near, we determined to follow that current for 40 minutes only: increafing our velocity by the ufe of our oars, we endeavoured to deviate from the direction of the current; but we could not obtain a deviation greater than 22 degrees towards the east. The length of our route, during about one hour and a quarter, was 2100 feet. Willing to try whether the wind nearer the earth was ftrong, we defcended to the height of 300 feet, where we met an exceedingly rapid current. At fome distance from Arras, we perceived a wood, over which we did not hefitate to pafs, though there was hardly any day-light upon the earth; and in 20 minutes time we came near Arras, on the plain of Beuvry, diftant nearly three quarters of a mile from Bethune, in Artois. As we could not diftinguifh, amongst the fhadows, the body of an old mill, upon which we were going to defcend, we avoided it by the help of our oars, and defcended amidst a numerous affembly of inhabitants."

'When they defcended, which was at 40 minutes past fix o'clock, there were above 200 pounds weight of ballaft still remaining in the boat. The way they had travelled was about 50 leagues, or 150 miles. The account of this voyage is concluded with the following remarks:-" Thofe experiments

* From aɛgos and caros, comes aeroftat, qui in aëre ftat; from thence, according to analogy, the fubftantive is formed, not by adding tion, but ation, Aeroftation must be derived from acroft, which has no meaning.

fhew,

1

fhew, that, far from going against the wind, as is faid by fome perfons to be poffible, in a certain manner, and fome aeronauts pretend to have actually done it; we have only obtained, by means of two oars, a deviation of 22 degrees; it is however certain, that if we could have ufed our four oars, we might have deviated about 40 degrees from the direction of the wind; and as our machine would have been capable of carrying seven perfons, it would have been eafy for five perfons to have gone, and to have put in action eight oars, by which means a devi-` ation of about 8 degrees might have been obtained.

We have already obferved, that if we did not deviate more than 22 degrees, it was because the wind carried us at the rate of 24 miles an hour: and it is natural to judge, that if the wind had been twice as ftrong as it was, we should not have deviated more than half what we actually did; and, on the contrary, if the wind had been only half as ftrong, our deviation would have been proportionably greater.'

Thefe remarks have fupplied a defect which we formerly complained of: but balloons of this fize can feldom be procured; for this was an oblong spheriod, nearly 47 feet by 28. But it is certainly poffible, by machinery, to increase the velocity of the ftrokes of the oar, by which the neceffary number of rowers would be greatly diminished. On the other

hand, the chance of violent currents, which the navigator can only rife above by the lofs of ballaft, or fink below by the diminution of his buoyant powers, will probably prevent any very permanent effect from such contrivances.

There is one chemical fact, in the relation of this and fome other voyages, which deferves attention. The heat of the inflammable air is always greater than that of the furrounding atmosphere, when the balloon is elevated to a confiderable height. In this experiment, the mercury in a thermometer, inferted into one of the appendices of the balloon, was raifed to 104, while the external one was only at 63°; and this internal heat could not arife from the larger mass of air not fo quickly acquiring the furrounding temperature, for the heat of the air near the earth feems not to have exceeded 77o. Inflammable air, we know, is more expanfile with a given degree of heat than common air; but this extraordinary increafe must be owing to other caufes. We are not acquainted with inftance in which latent heat is let loofe by expanfion on the contrary, it is generally abforbed. In the gra dual manner in which a balloon is filled, it is probable that the heat, raised by the effervefcence, is diffipated before the machine afcends.

any

The practice of aeroftation is explained with great perfpiçuity and exactnefs. The problems are not indeed demon

23

ftrated,

ftrated, but their foundation is evident: we would however recommend a previous trial of the fpecific gravity of the air produced in the particular operation; fince, in different experiments, there feems to be fome variety in this refpect.

Mr. Cavallo adds little to the means of directing balloons, or to the uses which we may derive from them. He corrects, with propriety, fome crude and inaccurate attempts, which we have formerly endeavoured to explode; but we think the purposes to which, in our author's opinion, they may be applied, will be more easily attained by other methods: to fome of them, particularly to the enquiry into the formation of clouds, rain, &c. we think they are inapplicable.

On the whole, this feems a very rational and entertaining performance if aeroftation is likely to be advantageous, we fhall join in the author's wish, that the learned and encou ragers of ufeful knowlege may unanimoufly concur in endeavouring to promote it.' Though we ftill continue in our former opinion, we would recommend proper and judicious trials, it is only to the childish fpectacles, and the extravagant and exaggerated relations, that we are enemies.

Comments on the loft Edition of Shakespeare's Plays. By John Monk Mafon. 8vo. 55. in Boards. Dilly.

SHALL we never reft from these labours ?-We have indeed great reafon to think that our repofe is ftill distant: as among fome of the ancient conquerors, when the enemy was fubdued, the ardour was fupported by inteftine feud,; so the commentators, when they have elucidated their author, contend with each other. Mr. Mafon had made a confiderable collection of materials for a new edition of our great dramatist, when Mr. Steevens' edition firft appeared, in which he owns, that many of his amendments and alterations were anticipated. He was fomewhat mortified at a difcovery, which compelled him to relinquifh a favourite purfuit, from whence he expected to derive fome degree of credit in the literary world.'

This however, he adds, was a fecondary confideration; and my principal purpofe will be answered to my with, if the Comments which I now fubmit to the public fhall, in any other hands, contribute materially to a more complete edition of our inimitable poet.'

Mr. Monk Mafon fome time fince publifhed an edition of Maflinger, of which we did not fpeak to his fatisfaction. He fays,

My having unfortunately afferted, in the Preface, that this edition of Maflinger would be found more correct than the best

of