The Roman History · Amm. 23.5.14

On the other hand, the philosophers declared that the brilliancy of this sacred fire thus suddenly presented to the eye had no special meaning, but was merely the course of a fiercer breath descending by some singular power from the sky to the lower parts of the world; and that if any foreknowledge were to be derived from such a circumstance, it was rather an increase of renown which was portended to the emperor now engaged in a glorious enterprise; since it is notorious that flame, if it meet with no obstacle, does of its own nature fly upwards.

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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