The military fame of Comentiolus is the object of satire or comedy rather than of serious history, since he was even deficient in the vile and vulgar qualification of personal courage. His solemn councils, strange evolutions, and secret orders always supplied an apology for flight or delay. If he marched against the enemy, the pleasant valleys of Mount Hæmus opposed an insuperable barrier; but in his retreat he explored with fearless curiosity the most difficult and obsolete paths, which had almost escaped the memory of the oldest native. The only blood which he lost was drawn, in a real or affected malady, by the lancet of a surgeon; and his health, which felt with exquisite sensibility the approach of the barbarians, was uniformly restored by the repose and safety of the winter season. A prince who could promote and support this unworthy favourite must derive no glory from the accidental merit of his colleague Priscus. In five successive battles, which seem to have been conducted with skill and resolution, 17,200 barbarians were made prisoners; near sixty thousand, with four sons of the chagan, were slain. The Roman general surprised a peaceful district of Gepidæ, who slept under the protection of the Avars; and his last trophies were erected on the banks of the Danube and the Theiss. Since the death of Trajan, the arms of the empire had not penetrated so deeply into the old Dacia; yet the success of Priscus was transient and barren, and he was soon recalled, by the apprehension that Baian, with dauntless spirit and recruited forces, was preparing to avenge his defeat under the walls of Constantinople. STATE OF THE ROMAN ARMIES The theory of war was not more familiar to the camps of Cæsar and Trajan than to those of Justinian and Maurice. The iron of Tuscany or Pontus still received the keenest temper from the skill of the Byzantine workmen. The magazines were plentifully stored with every species of offensive and defensive arms. In the construction and use of ships, engines, and fortifications, the barbarians admired the superior ingenuity of a people whom they so often vanquished in the field. The science of tactics, the order, evolutions, and stratagems of antiquity, were transcribed and studied in the books of the Greeks and Romans. But the solitude or degeneracy of the provinces could no longer supply a race of men to handle those weapons, to guard those walls, to navigate those ships, and to reduce the theory of war into bold and successful practice.