The Roman History · Amm. 31.9.2

They hastened accordingly, that by a rapid march they might carry out their proposed plan; but Frigeridus, who knew as well how to command as to preserve his troops, either suspected their plans, or else obtained accurate information respecting them from the scouts whom he had sent out; and therefore returned over the mountains and through the thick forests into Illyricum; being full of joy at the success which an unexpected chance threw in his way.

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
Passage preview. Read in context for the complete text, notes and references.