Yet by the impregnable fortifications with which the emperor encompassed his camp, he appeared to decline, rather than to invite, a general engagement.

It was the object of Magnentius to tempt or to compel his adversary to relinquish this advantageous position; and he employed, with that view, the various marches, evolutions, and stratagems, which the knowledge of the art of war could suggest to an experienced officer.

He carried by assault the important town of Siscia; made an attack on the city of Sirmium, which lay in the rear of the Imperial camp, attempted to force a passage over the Save into the eastern provinces of Illyricum; and cut in pieces a numerous detachment, which he had allured into the narrow passes of Adarne.

During the greater part of the summer, the tyrant of Gaul showed himself master of the field.

The troops of Constantius were harassed and dispirited; his reputation declined in the eye of the world; and his pride condescended to solicit a treaty of peace, which would have resigned to the assassin of Constans the sovereignty of the provinces beyond the Alps.