338 THE DECLINE AND FALL c H A P. glorious prosecution of the Persian war. He reconi- XVIII c 1 !_ mended the care of the east to his lieutenants, and afterwards to his cousin Gallus, whom he raised from a prison to a throne ; and mai'ched towards Europe, with a mind agitated by the conflict of hope and fear, of grief and indignation. On his arrival at Heraclea in Thrace, the emperor gave audience to the ambassa- dors of Magnentius and Vetranio. The first author of the conspiracy, Marcellinus, who in some measure had bestowed the purple on his new master, boldly accepted this dangerous commission ; and his three colleagues were selected from the illustrious personages of the state and army. These deputies were instructed to soothe the resentment, and to alarm the fears, of Con- stantius. They were empowered to ofter him the friendship and alliance of the western princes ; to ce- ment their union by a double marriage, of Constantius with the daughter of Magnentius, and of Magnentius himself with the ambitious Constantina; and to acknow- ledge in the treaty the preeminence of rank, which might justly be claimed by the emperor of the east. Should pride and mistaken piety urge him to refuse these equitable conditions, the ambassadors were or- dered to expatiate on the inevitable ruin which must attend his rashness, if he ventured to provoke the sove- reigns of the west to exert their superior strength ; and to employ against him that valour, those abilities, and those legions, to which the house of Constantine had been indebted for so many triumphs. Such pro- positions and such arguments api)eared to deserve the most serious attention ; the answer of Constantius was deferred till the next day ; and as he had reflected on the importance of justifying a civil war in the opinion of the people, he thus addressed his council, who list- ened with real or affected credulity. " Last night," said he, " after I retired to rest, the shade of the great Constantine, embracing the corpse of my murdered brother, rose before my eyes; his well-known voice awakened me to revenge, forbade me to despair of the i
