Autumn was already far advanced, and the season for military operations would, soon be over.

It was necessary, therefore, either to take the city speedily or to give up the siege and retire.

Under these circumstances Sapor resolved on a last effort.

He had constructed towers of such a height that they overtopped the wall, and poured their discharges on the defenders from a superior elevation.
He had brought his mounds in places to a level with the ramparts, and had compelled the garrison to raise countermounds within the walls for their protection.

He now determined on pressing the assault day after day, until he either carried the town or found all his resources exhausted.