The Roman History · Amm. 22.15.7

A more common opinion is, that during the continuance of the wind from the north, called the Precursor, and of the Etesian gales, which last forty-five days without interruption, they drive back the stream and check its speed, so that it becomes swollen with its waves thus dammed back; then, when the wind changes, the force of the breeze drives the waters to and fro, and the river growing rapidly greater, its perennial sources driving it forward, it rises as it advances, and covers everything, spreading over the level plains till it resembles the sea.

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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