the fwing wheel turns in an hard ruby, not for ornament but from neceffity; thefe ftones in fome measure fupplying the place of oil, which is ufually applied to clocks, to leffen the friction; but as part of the oil gradually hardens and becomes folid, thereby caufing irregularities in the movement, the best way was to get rid of it in fuch parts of the machinery as are most liable to be affected by its variation or cohesion. This was the primary motive for fubftituting rubies; and it is doubtless in confe quence of this, and other judicious alterations, fuch as cycloidal cheeks, that Mr. Arnold's time keepers are fo much fuperior to those of other artists. It has been found that agates are much too foft to answer the purpose of rubies; it is however to be wished, that fomething less coftly could be found out to anwer this purpose, and make the difcovery more generally useful.

When I fee, fays M. Mayer, that in the courfe of a year, Mr. Arnold's clock will vary no more than 3 or 4 feconds, my expectations are raifed, my pleafure is extreme; hereby aftronomers will have opportunities of difcovering fome ftill unknown irregularities in the diurnal rotation of the earth round her axis, in whatever fituation it may be through the whole year, at each distance from the fun.

It is greatly to be lamented, fays the Tranflator, that the few obfervatorics in Europe are not better provided with time-keepers, and inftruments of the most exact conftruction. There are ftill many material points in aftronomy to be fettled, and irregularities among the celeftial bodies whofe caufes are yet undifcovered, which probably might be investigated if greater exactnefs was employed in the obfervations. The variation of the places of feveral of the fixed stars, and the difference between the computed and obferved longitudes of the moon and planets, notwithstanding the late improvements, make this more than conjectural; and it is much to be regretted, that aftronomers have it not in their power to make farther and more accurate attempts, by being better provided with inftruments. To furnish fuch additional encouragements to fcience, is beyond the ability of moft private perfons; but, when confidered as a national expence, it is of all concerns the moft trifling. Unfortunately the examples of our gracious Sovereign, and the Bavarian Elector, are more admired than imitated.

You well know, fays M. Mayer, that, according to the experiments hitherto made, a change of 20 degrees in Reaumur's Thermometer makes an alteration of nearly 16 feconds in the daily going of common pendulum clocks; but in this, fuch alteration from the ift of September, to the 16th of December, amounted only to 1", 119; and yet this was the greatest error that happened in 131 days: a thing almoft incredible, and which does the highest honor to the English artift, Arnold!

W-db-e

Same as the preseding art!

ART.

ART. VII. Continuation of the Account of Mr. Gibbon's History of the Decline and Fall of the Roman Empire.

TH

THE twenty-feventh chapter of this History (the first of Vol. 3d.) opens with an account of the character and conduct of the Emperor Gratian, whofe fame, before he had accomplished the twentieth year of his age, was equal, Mr. Gibbon obferves, to that of the most celebrated princes. His gentle and amiable difpofition endeared him to his private friends, the graceful affability of his manners engaged the affection of the people: mcn of letters, who enjoyed the liberality, acknowledged the tafte and eloquence of their fovereign; his valour and dexterity in arms were equally applauded by the foldiers; and the cle gy confidered the humble piety of Gratian as the first and most useful of his virtues.

The victory of Colmar, continu ́s our Hiftorian, had delivered the Weft from a formidable invafion; and the grateful provinces of the Eaft afcribed the merits of Theodofius, to the author of his greatnels, and of the public fafety. Gratian furvived thofe memorable events only four or five years; but he furvived his reputation; and, before he tell a victim to rebellion, he bad loft, in a great measure, the refped and confidence of the koman world.

The remarkable alteration of his character or conduct, may not be imputed to the arts of flattery, which had befieged the fon of Valentinian from his infancy; nor to the headstrong paffions which that gentle youth appears to have efcaped. A more attentive view of the life of Gratian, may perhaps fuggeft the true caufe of the difappointment of the public hopes. His apparent virtues, instead of being the hardy productions of experience and adverfity, were the premature and artificial fruits of a royal education. The anxious tenderness of his father was continually employed to bellow on him thofe advantages, which he might perhaps eftcem the more highly. as he himself had been deprived of them; and the most skilful mafters of every science, and of every art, had laboured to form the mind and body of the young prince. The knowledge which they painfully communicated was difplayed with oftentation, and celebrated with lavish praife. His foft and tractable difpofition received the fair impreffion of their judicious precepts, and the abfence of paflion might easily be mistaken for the ftrength of reafon. His preceptors gradually rofe to the rank and confequence of minifters of ftate; and, as they wifely diffembled their fecret authority, he feemed to act with firmnefs, with propriety, and with judgment, on the most important occasions of his life and reign. But the influence of this elaborate inftruction did not penetrate beyond the furface; and the skilful preceptors, who fo accurately guided the fteps of their royal pupil, could not infufe into his feeble and indolent character, the vigorous and independent principle of action, which renders the laborious purfuit of glory effentially neceffary to the happiness, and almoft to the exiflence, of the hero. As soon as time and accident had removed thofe faithful counsellors from the throne, the emperor of the Weft infenfibly defcended to the level

of

of his natural genius; abandoned the reins of government to the ambitious hands which were ftretched forwards to grafp them; and amufed his leifure with the moft frivolous gratifications. A public fale of favour and injuftice was inftituted, both in the court, and in the provinces, by the worthlefs delegates of his power, whose merit, it was made facrilege to question. The confcience of the credulous prince was directed by faints and bishops; who procured an Imperial edict to punish, as a capital offence, the violation, the neglect, or even the ignorance, of the divine law. Among the various arts which had exercifed the youth of Gratian, he had applied himfelf, with fingular inclination and fuccefs, to manage the horfe, to draw the bow, and to dart the javelin; and thefe qualifications, which might be useful to a foldier, were prostituted to the viler purposes of hunting. Large parks were inclosed for the Imperial pleasures, and plentifully stocked with every fpecies of wild beafts; and Gratian neglected the duties, and even the dignity, of his rank, to confume whole days in the vain display of his dexterity and boldness in the chace. The pride and wish of the Roman emperor to excel in an art, in which he might be furpaffed by the meanest of his flaves, reminded the nume rous spectators of the examples of Nero and Commodus: but the chafte and temperate Gratian was a stranger to their monftrous vices; and his hands were ftained only with the blood of animals.

The behaviour of Gratian, which degraded his character in the eyes of mankind, could not have difturbed the fecurity of his reign, if the army had not been provoked to refent their peculiar injuries. As long as the young emperor was guided by the inftructions of his mafers, he profeffed himself the friend and pupil of the foldiers; many of his hours were spent in the familiar converfation of the camp; and the health, the comforts, the rewards, the honours, of his faithful troops, appeared to be the object of his attentive concern. But, after Gratian more freely indulged his prevailing tafte for hunting and fhooting, he naturally connected himself with the most dexterous ministers of his favourite amufement. A body of the Alani was received into the military and domestic service of the palace; and the admirable skill, which they were accustomed to display in the unbounded plains of Scythia, was exercifed, on a more narrow theatre, in the parks and inclofures of Gaul. Gratian admired the talents and customs of thefe favourite guards, to whom alone he entrusted the defence of his perfon; and, as if he meant to infult the public opinion, he frequently fhewed himself to the foldiers and people, with the dress and arms, the long bow, the founding quiver, and the fur garments, of a Scythian warrior. The unworthy spectacle of a Roman prince, who had renounced the dress and manners of his country, filled the minds of the legions with grief and indignation. Even the Germans, fo Atrong and formidable in the armies of the empire, affected to disdain the ftrange and horrid appearance of the favages of the North, who, in the space of a few years, had wandered from the banks of the Volga to thofe of the Seine. A loud and licentious murmur was echoed through the camps and garrifons of the Weft; and as the mild indolence of Gratian neglected to extinguish the firft fymptoms of difcontent, the want of love and respect was not supplied by the influence of fear. But the fubvertion of an eltablished government is always a

work

work of fome real, and of much apparent, difficulty; and the throne of Gratian was protected by the fanctions of cuftom, law, religion, and the nice balance of the civil and military powers, which had been established by the policy of Conftantine. It is not very important to inquire from what caufes the revolt of Britain was produced. Accident is commonly the parent of diforder; the feeds of rebellion happened to fall on a foil which was fuppofed to be more fruitful than any other in tyrants and ufurpers; the legions of that fequeftered ifland had been long famous for a fpirit of prefumption and arrogance; and the name of Maximus was proclaimed by the tumultuary, but unanimous voice, both of the foldiers and of the provincials. The emperor, or the rebel, for his title was not yet afcertained by fortune, was a native of Spain, the countryman, the fellow-foldier, and the rival of Theodofius, whofe elevation he had not feen without fome emotions of envy and refentment: the events of his life had long fince fixed him in Britain; and I should not be unwilling to find fome evidence for the marriage, which he is faid to have contracted with the daughter of a wealthy lord of Caernarvonshire. But this provincial rank might justly be confidered as a ftate of exile and obfcurity; and if Maximus had obtained any civil or military office, he was not invested with the authority either of governor or general. His abilities, and even his integrity, are acknowledged by the partial writers of the age; and the merit must indeed have been confpicuous, that could extort fuch a confeffion in favour of the vanquished enemy of Theodofius. The difcontent of Maximus might incline him to cenfure the conduct of his fovereign, and to encourage, perhaps, without any views of ambition, the murmurs of the troops. But in the midst of the tumult, he artfully, or modeftly, refufed to afcend the throne; and fome credit appears to have been given to his own pofitive declaration, that he was compelled to accept the dangerous prefent of the Imperial purple.'

In the remaining part of this chapter we have an account of the death of Gratian, the ruin of Arianifm, the first civil war against Maximus, the character, adminiftration, and penance of Theodofius, the death of Valentinian the fecond, the fecond civil war, against Eugenius, and the death of Theodofius.

The final deftruction of paganifm, and the introduction of the worship of faints and relics, among Chriftians, are the subjects of the twenty-eighth chapter. Mr. Gibbon introduces it with obferving that the Chriftians, more especially the clergy, had impatiently fupported the prudent delays of Conftantine, and the equal toleration of the elder Valentinian, and that they could not deem their conqueft perfect or fecure, as long as their adverfaries were permitted to exift. The influence, which Ambrofe and his brethren had acquired over the youth of Gratian, and the piety of Theodofius, was employed to infuse the maxims of perfecution into the breafts of their Imperial profelytes. Two fpecious principles of religious jurifprudence were established, we are told, from whence they deduced a di

rect and rigorous conclufion, against the fubjects of the empire, who still adhered to the ceremonies of their ancestors; that the magiftrate is, in fome measure, guilty of the crimes which he neglects to prohibit, or to punish; and that the idolatrous worfhip of fabulous deities, and real dæmons, is the most abominable crime against the fupreme majefty of the Creator. The laws of Mofes, and the examples of Jewifh hiftory, were haftily, perhaps erroneously, (Mr. Gibbon fays) applied by the clergy, to the mild and univerfal reign of Chriftianity. The zeal of the emperors was excited to vindicate their own honour, and that of the Deity: and the temples of the Roman world were fubverted, about fixty years after the converfion of Conftantine.

The philofophic reader will have peculiar fatisfaction in an attentive perufal of this chapter. The hiftorian's general reflections thew evidently that he has a clear and comprehenfive view of his fubject, and afford ftriking proofs of his fagacity and difcernment.

The twenty-ninth chapter contains an account of the final divifion of the Roman empire between the fons of Theodofius, of the reign of Arcadius and Honorius, the administration of Rufinus and Stilicho, the revolt and defeat of Gildo in Africa.

The revolt of the Goths, the two great invafions of Italy by Alaric and Radagaifus, the ufurpation of Conftantine in the Weft, the difgrace and death of Stilicho, are the fubjects of the thirtieth chapter.-In the thirty-firft, we have an interefting and original picture of the manners of Rome from Ammianus Marcellinus, who prudently chofe the capital of the empire, as the refidence the best adapted to the hiftorian of his own times, and who has mixed with the narrative of public events, a lively reprefentation of the fcenes with which he was familiarly converfant. The judicious reader, Mr. Gibbon obferves, will not always approve the afperity of cenfure, the choice of circumftances, or the ftyle of expreffion; he will perhaps detect the latent prejudices, and perfonal refentments, which foured the temper of Ammianus himself; but he will furely obferve, with philofophic curiofity, the ftriking picture of the manners of Rome.

Our hiftorian explains, in a note, the liberties he has taken with the text of Ammianus-he has melted down into one piece the fixth chapter of the fourteenth, and the fourth of the twenty-eighth book-he has given order and connexion to the confufed mafs of materials-he has foftened fome extravagant hyperboles, and pared away fome fuperfluities of the originalhe has developed fome obfervations which were infinuated, rather than expreffed. With thefe allowances, his verfion will be found, he thinks, not literal indeed, but faithful and exact,