Notwithstanding the policy of Diocletian, it was impossible to maintain an equal and undisturbed tranquillity during a reign of twenty years, and along a frontier of many hundred miles. Sometimes the barbarians suspended their domestic animosities, and the relaxed vigilance of the garrisons sometimes gave a passage to their strength or dexterity. Whenever the provinces were invaded, Diocletian conducted himself with that calm dignity which he always affected or possessed; reserved his presence for such occasions as were worthy of his interposition, never exposed his person or reputation to any unnecessary danger, insured his success by every means that prudence could suggest, and displayed, with ostentation, the consequences of his victory. In wars of a more difficult nature, and more doubtful event, he employed the rough valor of Maximian; and that faithful soldier was content to ascribe his own victories to the wise counsels and auspicious influence of his benefactor. But after the adoption of the two Caesars, the emperors themselves, retiring to a less laborious scene of action, devolved on their adopted sons the defence of the Danube and of the Rhine. The vigilant Galerius was never reduced to the necessity of vanquishing an army of barbarians on the Roman territory.[1257] The brave and active Constantius delivered Gaul from a very furious inroad of the Alemanni; and his victories of Langres and Vindonissa appear to have been actions of considerable danger and merit. As he traversed the open country with a feeble guard, he was encompassed on a sudden by the superior multitude of the enemy. He retreated with difficulty towards Langres; but, in the general consternation, the citizens refused to open their gates, and the wounded prince was drawn up the wall by the means of a rope. But, on the news of his distress, the Roman troops hastened from all sides to his relief, and before the evening he had satisfied his honor and revenge by the slaughter of six thousand Alemanni.[1258] From the monuments of those times, the obscure traces of several other victories over the barbarians of Sarmatia and Germany might possibly be collected; but the tedious search would not be rewarded either with amusement or with instruction.
The conduct which the emperor Probus had adopted in the disposal of the vanquished, was imitated by Diocletian and his associates. The captive barbarians, exchanging death for slavery, were distributed among the provincials, and assigned to those districts (in Gaul, the territories of Amiens, Beauvais, Cambray, Treves, Langres, and Troyes, are particularly specified)[1259] which had been depopulated by the calamities of war. They were usefully employed as shepherds and husbandmen, but were denied the exercise of arms, except when it was found expedient to enroll them in the military service. Nor did the emperors refuse the property of lands, with a less servile tenure, to such of the barbarians as solicited the protection of Rome. They granted a settlement to several colonies of the Carpi, the Bastarnae, and the Sarmatians; and, by a dangerous indulgence, permitted them in some measure to retain their national manners and independence.[1260] among the provincials, it was a subject of flattering exultation, that the barbarian, so lately an object of terror, now cultivated their lands, drove their cattle to the neighboring fair, and contributed by his labor to the public plenty. They congratulated their masters on the powerful accession of subjects and soldiers; but they forgot to observe, that multitudes of secret enemies, insolent from favor, or desperate from oppression, were introduced into the heart of the empire.[1261]
While the Caesars exercised their valor on the banks of the Rhine and Danube, the presence of the emperors was required on the southern confines of the Roman world. From the Nile to Mount Atlas Africa was in arms. A confederacy of five Moorish nations issued from their deserts to invade the peaceful provinces[1262] julian had assumed the purple at carthage.[1263] Achilleus at Alexandria, and even the Blemmyes, renewed, or rather continued, their incursions into the Upper Egypt. Scarcely any circumstances have been preserved of the exploits of Maximian in the western parts of Africa; but it appears, by the event, that the progress of his arms was rapid and decisive, that he vanquished the fiercest barbarians of Mauritania, and that he removed them from the mountains, whose inaccessible strength had inspired their inhabitants with a lawless confidence, and habituated them to a life of rapine and violence.[1264] Diocletian, on his side, opened the campaign in Egypt by the siege of Alexandria, cut off the aqueducts which conveyed the waters of the Nile into every quarter of that immense city,[1265] and rendering his camp impregnable to the sallies of the besieged multitude, he pushed his reiterated attacks with caution and vigor. After a siege of eight months, Alexandria, wasted by the sword and by fire, implored the clemency of the conqueror, but it experienced the full extent of his severity. Many thousands of the citizens perished in a promiscuous slaughter, and there were few obnoxious persons in Egypt who escaped a sentence either of death or at least of exile.[1266] the fate of busiris and of coptos was still more melancholy than that of Alexandria: those proud cities, the former distinguished by its antiquity, the latter enriched by the passage of the Indian trade, were utterly destroyed by the arms and by the severe order of Diocletian.[1267] the character of the egyptian nation, insensible to kindness, but extremely susceptible of fear, could alone justify this excessive rigor. The seditions of Alexandria had often affected the tranquillity and subsistence of Rome itself. Since the usurpation of Firmus, the province of Upper Egypt, incessantly relapsing into rebellion, had embraced the alliance of the savages of Aethiopia. The number of the Blemmyes, scattered between the Island of Meroe and the Red Sea, was very inconsiderable, their disposition was unwarlike, their weapons rude and inoffensive.[1268] yet in the public disorders, these barbarians, whom antiquity, shocked with the deformity of their figure, had almost excluded from the human species, presumed to rank themselves among the enemies of Rome.[1269] such had been the unworthy allies of the Egyptians; and while the attention of the state was engaged in more serious wars, their vexatious inroads might again harass the repose of the province. With a view of opposing to the Blemmyes a suitable adversary, Diocletian persuaded the Nobatae, or people of Nubia, to remove from their ancient habitations in the deserts of Libya, and resigned to them an extensive but unprofitable territory above Syene and the cataracts of the Nile, with the stipulation, that they should ever respect and guard the frontier of the empire. The treaty long subsisted; and till the establishment of Christianity introduced stricter notions of religious worship, it was annually ratified by a solemn sacrifice in the Isle of Elephantine, in which the Romans, as well as the barbarians, adored the same visible or invisible powers of the universe.[1270]
At the same time that Diocletian chastised the past crimes of the Egyptians, he provided for their future safety and happiness by many wise regulations, which were confirmed and enforced under the succeeding reigns.[1271] one very remarkable edict which he published, instead of being condemned as the effect of jealous tyranny, deserves to be applauded as an act of prudence and humanity. He caused a diligent inquiry to be made «for all the ancient books which treated of the admirable art of making gold and silver, and without pity, committed them to the flames; apprehensive, as we are assumed, lest the opulence of the Egyptians should inspire them with confidence to rebel against the empire.»[1272] but if diocletian had been convinced of the reality of that valuable art, far from extinguishing the memory, he would have converted the operation of it to the benefit of the public revenue. It is much more likely, that his good sense discovered to him the folly of such magnificent pretensions, and that he was desirous of preserving the reason and fortunes of his subjects from the mischievous pursuit. It may be remarked, that these ancient books, so liberally ascribed to Pythagoras, to Solomon, or to Hermes, were the pious frauds of more recent adepts. The Greeks were inattentive either to the use or to the abuse of chemistry. In that immense register, where Pliny has deposited the discoveries, the arts, and the errors of mankind, there is not the least mention of the transmutation of metals; and the persecution of Diocletian is the first authentic event in the history of alchemy. The conquest of Egypt by the Arabs diffused that vain science over the globe. Congenial to the avarice of the human heart, it was studied in China as in Europe, with equal eagerness, and with equal success. The darkness of the middle ages insured a favorable reception to every tale of wonder, and the revival of learning gave new vigor to hope, and suggested more specious arts of deception. Philosophy, with the aid of experience, has at length banished the study of alchemy; and the present age, however desirous of riches, is content to seek them by the humbler means of commerce and industry.[1273]
1257
He complained, though not with the strictest truth, «Jam fluxisse annos quindecim in quibus, in Illyrico, ad ripam Danubii relegatus cum gentibus barbaris luctaret.» Lactant. de M. P. c. 18.
1258
In the Greek text of Eusebius, we read six thousand, a number which I have preferred to the sixty thousand of Jerome, Orosius Eutropius, and his Greek translator Paeanius.
1260
There was a settlement of the Sarmatians in the neighborhood of Treves, which seems to have been deserted by those lazy barbarians. Ausonius speaks of them in his Mosella:- «Unde iter ingrediens nemorosa per avia solum, Et nulla humani spectans vestigia cultus;… Arvaque Sauromatum nuper metata colonis."
1261
There was a town of the Carpi in the Lower Maesia. See the rhetorical exultation of Eumenius.
1262
Scaliger (Animadvers. ad Euseb. p. 243) decides, in his usual manner, that the Quinque gentiani, or five African nations, were the five great cities, the Pentapolis of the inoffensive province of Cyrene.
1263
After his defeat, Julian stabbed himself with a dagger, and immediately leaped into the flames. Victor in Epitome.
1264
Tu ferocissimos Mauritaniae populos inaccessis montium jugis et naturali munitione fidentes, expugnasti, recepisti, transtulisti. Panegyr Vet. vi. 8.
1266
Eutrop. ix. 24. Orosius, vii. 25. John Malala in Chron. Antioch. p. 409, 410. Yet Eumenius assures us, that Egypt was pacified by the clemency of Diocletian.
1267
Eusebius (in Chron.) places their destruction several years sooner and at a time when Egypt itself was in a state of rebellion against the Romans.
1268
Strabo, l. xvii. p. 172. Pomponius Mela, l. i. c. 4. His words are curious: «Intra, si credere libet vix, homines magisque semiferi Aegipanes, et Blemmyes, et Satyri."
1270
See Procopius de Bell. Persic. l. i. c. 19. Note: Compare, on the epoch of the final extirpation of the rites of Paganism from the Isle of Philae, (Elephantine,) which subsisted till the edict of Theodosius, in the sixth century, a dissertation of M. Letronne, on certain Greek inscriptions. The dissertation contains some very interesting observations on the conduct and policy of Diocletian in Egypt. Mater pour l'Hist. du Christianisme en Egypte, Nubie et Abyssinie, Paris 1817-M.
1271
He fixed the public allowance of corn, for the people of Alexandria, at two millions of medimni; about four hundred thousand quarters. Chron. Paschal. p. 276 Procop. Hist. Arcan. c. 26.
1273
See a short history and confutation of Alchemy, in the works of that philosophical compiler, La Mothe le Vayer, tom. i. p. 32–353.