The Roman History · Amm. 18.8.2

But we met with a sad disaster, worthy to be buried in profound silence. For two squadrons of cavalry, of about seven hundred men, who had just been sent from Illyricum to Mesopotamia as a reinforcement, and who were guarding the passes, becoming enervated and timid, and fearing a surprise by night, withdrew from the public causeways in the evening, a time above all others when they most required watching.

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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