Titus Livius (Livy), The History of Rome, Book 42
Evan T. Sage, Ph.D. and Alfred C. Schlesinger, Ph.D., Ed.

66. When the first standards of their fellows came in sight of the beleaguered, the spirits of the Romans indeed were revived from the depths of despair. [2] Perseus, whose best course of all would have been to be satisfied with his chance success in capturing and killing a certain number of foragers, and not to waste time besieging the guard, [3??] or, as second best, after trying the latter enterprise too in some fashion, when he became aware that he had no strength on his side, to depart unscathed while he might —Perseus, puffed up by success, both awaited the approach of the enemy himself and sent men hastily to summon the phalanx; [4] this being brought up later than circumstances required and in haste, would have come in confusion from its [p. 501]forced march against men in formation and ready.¹ The consul, arriving first, immediately joined battle. [5] At first the Macedonians stood fast; then, as they were in no respect equally matched, with a loss of three hundred infantry and twenty-four of their finest cavalrymen from the squadron which they call sacred,² among whom also fell Antimachus the squadron commander, they attempted to retreat. However, the march was almost more of a hurly-burly than the battle itself. [6] While the phalanx, summoned by an alarmed messenger, was being hastily led up, first meeting the column of prisoners and the wagons laden with grain in some narrows, it was stuck. [7] Thereupon there was great turmoil on both sides, with no one waiting till somehow or other the column should be disentangled, but with the men-at-arms hurling the obstructing wagons down the steep slope —for the road could not otherwise be cleared —and the draft-animals, as they were goaded, lashing out at the crowd. [8] Hardly had they freed themselves from the disorganized column of prisoners when they ran into the king's column and the routed cavalry. Then indeed the shouting of those ordering a retreat also produced an alarm almost like a complete disaster, so that if the enemy, daring to enter the narrows, had pursued farther, a great loss might have been incurred. [9] The consul, having picked up the guard from the hill and being satisfied with a moderate success, led his troops back to camp. There are those who declare that a great battle was fought on that day, that eight thousand of the enemy [p. 503]were killed, among them Sopater and Antipater,³ officers of the king, that there were taken alive about two thousand and eight hundred, and that twenty-seven military standards were taken. [10] Nor was the victory bloodless, they say; more than four thousand and three hundred of the consul's army fell, and five standards of the left squadron were lost.