The Roman History · Amm. 17.12.4

Therefore, after the vernal equinox was past, the emperor, having collected a strong body of soldiers, marched forth under the guidance of propitious fortune. Having arrived at a suitable place, he crossed the Danube, which was now flooded from the melting of the snow, by a bridge of boats, and descended on the lands of the barbarians, which he began to lay waste. They, being taken by surprise through the rapidity of his march, and seeing that the battalions of his warlike army were at their throats, when they had not supposed it possible that such a force could be collected for a year, had no courage to make a stand, but, as the only means of escaping unexpected destruction, took to flight.

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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