as a mark of the Chriftians having been defeated.' To this may be added, that notwithstanding the Duke of Beaufort's rank, the Governor of the Baftile would never have shewa fo much refpect towards him as he fhewed towards this prifoner, and the detention of this nobleman would have been on the part of Lewis XIV. or his miniftry, a piece of cruelty equally useless and ridiculous. A fecond opinion is, that this perfonage was the Count de Vermandois, fon of Louis XIV. by Madame de la Valliere. This opinion, founded upon the relation of the author of Secret Memoirs, was fupported alfo by the Jefuit Griffet, a long time confeffor to the Bastile, who had an opportunity of fearching the most private archieves of that prison, and whofe evidence on this account may be confidered as having fome weight. In the Secret Memoirs, the following account is given of this affair. The Count 'de Vermandois, natural fon of Louis * XIV. one of his greatest favourites, and almost of the fame age as the • Dauphin, but of a quite different difpofition, forgot himself fo far one day, as to give the young Prince a box on the ear. This action having ⚫ been too public to remain unpunished, the King made him join the army, and fent word to one of his confidants to spread a report foon * after his arrival, that he was attack⚫ed by a contagious diforder, to prevent any one from being around him; afterwards, to give out that he was dead, and while his pretend⚫ed funeral should be celebrated with great pomp and fplendour before the eyes of the whole army, to convey him with the utmost fecrecy to ⚫ the ifle of St Margaret, which was punctually executed. The Count de Vermandois never quitted this 'prifon till he was conveyed to the Baftile, where he died fome years • after.' The relater of this anecdote be- gins by faying, that the Dauphin and the Count de Vermandois were almost of the fame age, but this is a mistake. The Dauphin was born in 1661, and was confequently fix years older than the Count de Vermandois, who was born in 1667. At the time when the pretended blow was given, the Count was fixteen years of age, and the Dauphin twenty-two; the latter was alfo married, and had a fon, known by the title of the Duke of Burgundy. They were therefore too far advanced in life to quarrel like mere children; besides, the Count de Vermandois was mild, affable, and polite, and his figure difplayed all the graces of his mo ther. Towards the end of the year 1682, Louis XIV. having difcovered that he had been engaged in fome extravagant debauch, after a fevere reprimand, banished him from the court for fome time. He did not appear there again till towards the end of October 1683, to take his leave before he fet out on his first campaign, which abfolutely refutes the ftory concerning the box on the ear given to the Dauphin. This circumitance is not faid to have happened before his difgrace; it must then have taken place after his return; but it is certain, that he remained at court only four days, which must have been otherwise employed, and that he was befides greatly mortified with the punishment he had fuffered, and far from being inclined to any excefs. It may be observed alfo, that there were too many attendants around the Dauphin, not to make fuch a rafh action immediately public. All the accounts of that time fay, that the Count de Vermandois was taken ill on the 12th of November in the evening, that a malignant fever appeared the next day, and that he died on the 18th. Louis XIV. and all his ministers, could not have communicated that fever to him. They must therefore therefore have been under the neceffity of perfuading this paffionate and rafh prince to act the fick man for fix days; they muft alfo have bribed or gained over his phyficians, and fecured the confidence of Goflas the priest, whom Madame de la Valliere engaged to attend her fon to the army, and who came back inconfolable for the lofs of his young master, after having feen him breathe his laft. All these improbabilities give us reason to disbelieve that the man with the iron mask was the Count de Vermandois. With regard to age, that of the man with the iron mask agrees as little with the age of the Count de Vermandois, as with that of the Duke of Beaufort; the one was by far too young, and the other by far too old. A third opinion is, that this prifoner was the Duke of Monmouth, natural fon of Charles II. king of England, by Lucy Walters. The great affection which the people of England entertained for this nobleman, and an idea he had conceived that they only wanted a leader to drive James II. from the throne, engaged him to undertake an enterprize, which might have perhaps fucceeded, had it been conducted with more prudence. Having landed at Lyme, in Dorfetfhire, with fcarcely an hundred followers, he foon faw his little army encreased to the number of fix thousand men. Several towns declared for him, and, encouraged by the favourable reception which he had met with, he affumed the title of King, maintained his legitimacy, and declared that he had proofs of the marriage of Charles II. with his mother. James alarmed at his progrefs, fent a confider M able body of men to oppofe him; battle was fought in the neighbour. hood of Bridgewater, in which Monmouth's party were at firft fuperior; but, being bafely deferted by Lord Gray, who commanded the cavalry, they foon began to give way, and, after a fhort conflict, were entirely defeated. The unhappy Monmouth, in attempting to effect his escape, was taken prifoner, and, being conveyed to London, was beheaded on the 15th of July 1685. This execution was attended with all the usual formalities; but Mr Hume tells us, that his partifans flattered themfelves, and not without fome foundation, that the perfon put to death was not the Duke of Monmouth, but one of his most faithful adherents, who refembled that nobleman, and who, being caught, had the courage to die in his ftead, and to give him that proof of his zeal and attachment. It is certain, that a report prevailed in London, that an officer of his army had fuffered for him, and, on this report, a lady of great quality having, by the force of money, prevailed upon those who had it in their power to open the coffin, and, having examined the right arm of the body, inftantly exclaimed, Ah, It is not he! But without dwelling on popular reports, the timorous character of James II. and the political circumftances of the times, feem to corref pond very well with this opinion. With regard to another perfon fubftituting himself in the place of the Duke of Monmouth, there is nothing impoffible in this, when it is confidered how much he was beloved and adored by his friends. An Account of the Principal Ancient Measures and Weights. a work, entitled, Metrologie; or, and hd Meafüres of the ancients, and, in a particular manner, for determining the value of the Greek and Roman money, and the proportions thefe bear to the prefent weights, measures, and money of France. A work of this kind is very remote from the fubjects about which the author is, in general, converfant, but the whole time of this celebrated naturalift is dedicated to labour; he lofes none of it in cringing at Court, in intriguing, caballing, and foliciting places. Accordingly, say the editors of Rozier's Journal, M. Romé de L'Isle, whose name will last as long as fcience fhall be cultivated, though honoured by foreigners, and affociated with the most learned focieties of Europe, has still been elected a member of no Academy in France, nor has he any place. Places and penfions, our academicians have now contrived to lavish away with the prodigality and partiality of courtiers. But the public efteem will undoubtedly indemnify this valuable citizen for an injuftice which the nation difavows. Academical aristocracy is not lefs injurious to the republic of letters, than patrician ariftocracy to political conftitutions. From the above work the follow. ing is a fhort extract : A knowledge of the proportions of ancient measures with our own, fays the author, is fo neceffary to the understanding of ancient hiftory, that many learned men have made it the object of investigation. A knowledge of these measures is not foreign to the phyfical fciences, and it confirms us in our high opinion of the knowledge of the ancients. The different foot-meafures, which they made ufe of, may be referred to two principal ones, the pes geometricus and the pes pythicus. The geometric foot was fixed at the four hundred thousandth part of a degree of the meridian. This foot was 10 inches, 3,31 lines, 400,000 of which give, according to the most exact modern measures, 570667 toifes for the extent of a degree of the meridian. The cubit of the Nile was equal to two geometric feet confequently there were 200,000 of them in a degree. The Alexandrian ftadium contained 800 geometric feet, and 400 cubits of the Nile, confequently a degree contained 500 of thefe.Each fide of the great pyramid was the length of an Alexandrian stadium, or the part of a degree. The pythic, or delphic foot, was calculated by the length of a pendulum. M. Bouguer has fhewn, that the length of the pendulum, which vibrates in a fecond, ought to be under the equator 36 inches 7,21 lines, and, at Paris, 36 inches 8,67 lines. The quarter of the fecond pendulum would therefore at Paris be 110,17 lines, or 9 inches 2,17 lines. Now, the pythic foot is 9 inches 1,48 lines, a fmall difference, which is occafioned by the difference of latitude between Egypt and Paris. From this we may fee how profound the knowledge was which the ancients poffeffed. The weights were taken from the cubes of the measures. Thus the Roman foot confifted of 10 inches, 10,60 lines, the cube of which, viz. 1292 inches, gave the amphora, which weighed 80 pounds. The culeus contained 20 amphoræ, and weighed 1600 pounds. The urna was the half of the amphore, and weighed 40 pounds. The congius was the eighth part of the amphora, and weighed 10 pounds. The congius contained 6 fextarii, 12 heminæ, 24 quartarii, 48 acetabula, 72 cyathi, 144 demi-cyathi, and 288 ligula. The Roman pound weighed 10 ounces 4 drachms of the French poids de marc. It confifted of 12 Xx 2 Bunces. ounces. Each ounce was compofed of 8 drachms, or 24 fcruples, and each scruple of 21 grains. M. Romé de L'Ifle, has certified himself of the juftness of these weights, by accurately weighing the medals in the fine collection of M. d'Ennery. It has been long talked of in Europe, fay the authors of this Journal, to have an uniform standard of meafures. What can we do better than to imitate the measures of the an cients, either by adopting the geometrical foot taken from the measurement of a degree of the meridian, or the pythic foot taken from the length of a pendulum vibrating feconds, which ftill fubfifts at Marseilles (and at Genoa, under the name of Palm. We might fubftitute the word fadium for mile. Defcription of Coalbrookdale, and of the Iron Bridge over the Severn, THE THE valley of Coalbrookdale is fituated in Shropshire, eastward of Wales. It is fomewhat narrow, and is watered by the river Severn. It is one of the principal places for the manufacture of iron in England. You go to it through Shrewsbury, the capital of Shropshire; or, by the way of Ludlow, the ancient refidence of the Princes of Wales, whofe caftle ftill remains there. After having passed over a few hills, that fingular valley comes all at once into view, from whence, night and day, there arife clouds of fire and smoke, forming a picture more eafily imagined than defcribed. Nothing would be more difmal than this fcene, if it did not exhibit the image of industry, and confequently make one conclude the condition of its inhabitants to be comfortable. Vegetation here is feeble and fcanty, as in all countries where there are mines; the grafs has not that beautiful verdure fo admired in England, and which is become in fome degree a mark of the national luxury; for it is incredible to think what facrifices are made by the nobility and gentry of England, for the perfecting and keeping in repair the turf of their parks and of their grafs walks. The trees are few in this valley, they are funted in their growth, and bare of leaves; the ground, at every step, prefents fragments of iron and coal, and the dark orifices of the pits dug for the extraction of these useful minerals. The birds, that animate and enliven country fcenes, fly from this bleak and barren fpot; and the most comfortless filence would reign throughout the whole valley, were it not disturbed by the noife of forges, of fire-engines, and of furnaces. This first impreffion is foon effaced by the interefting spectacle of a numerous and hardy race of people, the efforts of whofe industry have been fo fuccefsfully employed in taking advantage of thofe materials which Nature here offers for the use of the arts. Houfes are feen scattered on all hands filled with a prodigious number of workmen, enormous maffes of iron and of coal, vaft furnaces, forges continually at work, iron waggons loaded with manufactures of the fame metal; and, lastly, the famous iron bridge which joins the two banks of the Severn, a monument unique in its kind. At the extremity of this bridge ftands the inn of Coalbrookdale; above which the ground rifes to a great height in the form of a cone; on the fummit of this eminence an elegant elegant temple has been built in the antique tafte, which forms a very agreeable vifta. Nature feems to have bestowed on this valley every thing that is neceffary for the manufacture of iron: the ores of this metal are often contiguous to the coal; they are fometimes found in alternate ftrata; limeftone, which abounds here, is a valuable flux for the melting of the oar; the neighbouring hills furnish abundance of wood; a rivulet, which falls into the river, is fufficient for turning the different wheels, and working the different hammers for which there is occafion; and, lastly, the river, which has a communication with various canals, facilitates the tranfportation of these valuable manufactures. Coal is fo abundant in Coalbrookdale, that a ton, weighing two thoufand two hundred pounds, coft a few years ago only two fhillings and fixpence; but the price is now advanced to four fhillings the ton. Nature, no doubt, has done much for this valley; but what means has Art not fallen upon to profit by her gifts! one cannot fufficiently admire its refources. Here we have a full view of the astonishing effects of thofe fire, or fteam-engines that were brought to perfection by Meffrs Watt and Bolton, by means of which, advantage has been taken of the immenfe power of vapour to operate what no other mechanical force was equal to. The principal improvement, invented by these illuftrious artifts, confifts in making use of the action of the fteam to force down the pifton, which formerly was allowed to fink by the mere weight of the atmofphere, while now the force of the team feels no refiftance but from the cylinders in which it is contained. One of these steam-engines is em ployed in raifing the water of the rivulet I mentioned above to the height of an hundred feet. It is collected into a refervoir at a small distance from its fall; a fubterraneous canal conducts it back again by a gentle declivity, immediately under the machine, which, by railing the water, augments the volume of the rivulet and increases it, so to fpeak, at pleasure, in proportion to the number of wheels it is wanted to turn. The cylinder of this fteamengine is 66 inches in diameter: I faw one of eight feet in diameter, which was deftined for the bellows of one of the forges. At a fmall diftance from the house is a large furnace in which the ore is melted. This furnace, in the year 1787, had been kept burning for ten years without interruption a remarkable circumstance, for these furnaces, in general, do not last so long. The fufed matter is made to run out twice a-day on a stratum of fand, where it follows the courfe that has been marked out for it, and forms long roads called Sows, which the workmen divide into pigs before it be quite cooled. The vaft bellows that maintain this fire make a noise which one cannot, without having heard it, form any idea of. They are managed by a fingle man, who proportions the force of the blast to the degree of ftrength that is meant to be given to the fire. In thefe workhoufes there reigns a fuffocating heat, which custom enables the workmen to endure close to the furnace, while other people are obliged to remain at a confiderable diftance: but the ftrength of this dazzling fire is equally injurious to the eyes and to the lungs of the workmen, who have generally a weak and broken voice, and a languid appearance. From this you pass to the forges, where the melted matter, known by the name of fes, is fubjected to a fecond procefs. In this operation it is not reduced to the ftate of fufion, but only foftened by the action of the fire; and it is then laid below hammers, which are |