The Roman History · Amm. 21.13.2

But while still undecided, he was detained by various causes. Sapor also remained on the other side of the Tigris till the sacrifices should become propitious to his moving. For if after crossing the river he found no resistance, he might without difficulty penetrate to the Euphrates. On the other hand, if he wished to keep his soldiers for the civil war, he feared to expose them to the dangers of a siege; having already experienced the strength of the walls and the vigour of the garrison.

Ammianus Marcellinus · translated by C. D. Yonge · 1911 reprint
C. D. Yonge translation (preface dated February 1862); G. Bell and Sons, 1911; Project Gutenberg #28587
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