The Prætorian bands, whose licentious fury was the first symptom and cause of the decline of the Roman empire, scarcely amounted to the last-mentioned number.* They derived their institution from Augustus. That crafty tyrant, sensible that laws might color, but that arms alone could maintain, his usurped dominion, had gradually formed this powerful body of guards, in constant readiness to protect his person, to awe the senate, and either to prevent or to crush the first motions of rebellion. He distinguished these favored troops by a double pay and superior privileges; but, as their formidable aspect would at once have alarmed and irritated the Roman people, three cohorts only were stationed in the capital, whilst the remainder was dispersed in the adjacent towns of Italy. But after fifty years of peace and servitude, Tiberius ventured on a decisive measure, which forever rivetted the fetters of his country. Under the fair pretences of relieving Italy from the heavy burden of military quarters, and of introducing a stricter discipline among the guards, he assembled them at Rome, in a permanent camp, which was fortified with skilful care, and placed on a commanding situation. Such formidable servants are always necessary, but often fatal to the throne of despotism. By thus introducing the Prætorian guards as it were into the palace and the senate, the emperors taught them to perceive their own strength, and the weakness of the civil government; to view the vices of their masters with familiar contempt, and to lay aside that reverential awe, which distance only, and mystery, can preserve towards an imaginary power. In the luxurious idleness of an opulent city, their pride was nourished by the sense of their irresistible weight; nor was it possible to conceal from them, that the person of the sovereign, the authority of the senate, the public treasure, and the seat of empire, were all in their hands. To divert the Prætorian bands from these dangerous reflections, the firmest and best established princes were obliged to mix blandishments with commands, rewards with punishments, to flatter their pride, indulge their pleasures, connive at their irregularities, and to purchase their precarious faith by a liberal donative; which, since the elevation of Claudius, was enacted as a legal claim, on the accession of every new emperor.