2. The next object of Ca'rus was to punish the murderers of Pro'bus, and procure public tranquillity. Several nations of the west having revolted, he sent his son Cari'nus against them, and advanced himself against the Sarma'tians, whom he defeated, with the loss of sixteen thousand men killed, and twenty thousand prisoners. Soon after this he entered Persia, and removed to Mesopota'mia. Vera'nes the second, king of Persia, advancing against him, was defeated, and lost Ctes'iphon, his capital. This conquest gained Ca'rus the surname of Per'sieus; but he had not enjoyed it long, when he was struck dead, by lightning, in his tent, with many of his attendants, after a reign of about sixteen months. Upon the death of Ca'rus, the imperial power devolved on his sons Cari'nus and Nume'rian, who reigned jointly. In the first year of their accession, having made peace with the Persians, Cari'nus advanced against Ju'lian, who had caused himself to be proclaimed in Vene'tia,[5] and whom he defeated; when he returned again into Gaul. 3. Cari'nus was at this time in Gaul, but Nume'rian, the younger son, who accompanied his father in his expedition was inconsolable for his death, and brought such a disorder upon his eyes, with weeping, that he was obliged to be carried along with the army, shut up in a close litter. 4. The peculiarity of his situation, after some time, excited the ambition of A'per, his father-in-law, who supposed that he could now, without any great danger, aim at the empire himself. He therefore hired a mercenary villain to murder the emperor in his litter; and, the better to conceal the fact, gave out that he was still alive, but unable to endure the light. 5. The offensive smell, however, of the body, at length discovered the treachery, and excited an universal uproar throughout the whole army. 6. In the midst of this tumult, Diocle'sian, one of the most noted commanders of his time, was chosen emperor, and with his own hand slew A'per, having thus, as it is said, fulfilled a prophecy, that Diocle'sian should be emperor after he had slain a boar.[6] [Sidenote: U.C. 1057. A.D. 284.] 7. Diocle'sian was a person of mean birth; he received his name from Dio'clea, the town in which he was born, and was about forty years old when he was elected to the empire. He owed his exaltation entirely to his merit; having passed through all the gradations of office with sagacity, courage, and success.