The Roman History · Amm. 25.6.12

But the emperor and his officers opposed this demand, and showed them that the river, now just at the time of the rising of the Dogstar, was much flooded, entreated them not to trust themselves to its dangerous currents, reminding them that most of them could not swim, and adding likewise that the enemy had occupied the banks of the river, swoln as it was at many parts.

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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