The good sense of Vespasian engaged him indeed to embrace every measure that might confirm his recent and precarious elevation. The military oath, and the fidelity of the troops, had been consecrated, by the habits of a hundred years, to the name and family of the Cæsars; and although that family had been continued only by the fictitious rite of adoption, the Romans still revered, in the person of Nero, the grandson of Germanicus, and the lineal successor of Augustus. It was not without reluctance and remorse, that the prætorian guards had been persuaded to abandon the cause of the tyrant. The rapid downfall of Galba, Otho, and Vitellus, taught the armies to consider the emperors as the creatures of _their_ will, and the instruments of _their_ license. The birth of Vespasian was mean: his grandfather had been a private soldier, his father a petty officer of the revenue; his own merit had raised him, in an advanced age, to the empire; but his merit was rather useful than shining, and his virtues were disgraced by a strict and even sordid parsimony. Such a prince consulted his true interest by the association of a son, whose more splendid and amiable character might turn the public attention from the obscure origin, to the future glories, of the Flavian house. Under the mild administration of Titus, the Roman world enjoyed a transient felicity, and his beloved memory served to protect, above fifteen years, the vices of his brother Domitian. Nerva had scarcely accepted the purple from the assassins of Domitian, before he discovered that his feeble age was unable to stem the torrent of public disorders, which had multiplied under the long tyranny of his predecessor. His mild disposition was respected by the good; but the degenerate Romans required a more vigorous character, whose justice should strike terror into the guilty. Though he had several relations, he fixed his choice on a stranger. He adopted Trajan, then about forty years of age, and who commanded a powerful army in the Lower Germany; and immediately, by a decree of the senate, declared him his colleague and successor in the empire. It is sincerely to be lamented, that whilst we are fatigued with the disgustful relation of Nero’s crimes and follies, we are reduced to collect the actions of Trajan from the glimmerings of an abridgment, or the doubtful light of a panegyric. There remains, however, one panegyric far removed beyond the suspicion of flattery. Above two hundred and fifty years after the death of Trajan, the senate, in pouring out the customary acclamations on the accession of a new emperor, wished that he might surpass the felicity of Augustus, and the virtue of Trajan.