Appian of Alexandria Civil Wars 2.11.78

[78] While they were waiting and looking at each other the day was advancing. All the Italian troops stood motionless in their places, but when Pompey saw that his allied forces were falling into confusion by reason of the delay he feared lest the disorder should spread from them before the beginning of the battle. So he gave the signal first and Caesar reëchoed it. Straightway the trumpets, of which there were many distributed among so great a host, aroused the soldiers with their inspiring blasts, and the standard-bearers and officers put themselves in motion and exhorted their men. The latter advanced confidently to the encounter, but with stolidity and absolute silence, like men who had had experience in many similar engagements. And now, as they came nearer together, there was first a discharge of arrows and stones. Then as the cavalry were a little in advance of the infantry they charged each other. Those of Pompey prevailed and began to flank the tenth legion. Caesar then gave the signal to the cohorts in ambush and these, starting up suddenly, advanced to meet the cavalry, and with spears elevated aimed at the faces of the riders. The latter could not endure the enemy’s savagery, nor the blows on their mouths and eyes, but fled in disorder. Thereupon Caesar’s men, ¹ who had just now been afraid of being surrounded, fell upon the flank of Pompey’s infantry which was denuded of its cavalry supports.