The Roman History · Amm. 25.3.2

And while our flanks were strongly guarded, and the army proceeded onward in as good order as the nature of the ground would allow, being formed in squares, though not quite closed up, suddenly news was brought to the emperor, who had gone on unarmed to reconnoitre the ground in front, that our rear was attacked.

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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