Res Gestae

And now, when the mounds were raised still higher, the garrison, fearing that destruction would soon be upon them unless they should rouse themselves, resorted to utter recklessness. Making a sudden rush through the gates, they attacked the foremost of our men, with all their strength hurling upon the rams firebrands and baskets made of iron and filled with flames.

But after fighting with shifting fortune the greater number were driven back within the walls without effecting anything. Then those same Persians, when they had taken their place on the bulwarks were assailed from the mounds, which the Romans had raised, with arrows, sling-shots, and fiery darts, which, however, though they flew through the coverings of the towers, for the most part fell without effect, since there were men at hand to put out the fires.

And when the fighting men on both sides became fewer, and the Persians were driven to the last extremity unless some better plan should suggest