Titus Livius (Livy), The History of Rome, Book 37
Evan T. Sage, PhD professor of latin and head of the department of classics in the University of Pittsburgh, Ed.

41. The king himself was on the right flank; he placed his son Seleucus and Antipater the son of his brother on the left; the centre of the line was entrusted to three commanders, Minnio and Zeuxis and Philippus, the master of the elephants.¹

[2] A morning mist, lightening into clouds as the day advanced, caused a fog; the moisture from this, like a rain brought on by the west wind, covered everything; [3] these conditions brought absolutely no discomfort to the Romans, but at the same time they were very inconvenient for the king's army; for the faintness of the light, in a line of moderate frontage, [p. 411]did not deprive the Romans of a view in all directions,² and the moisture, in a force almost entirely composed of heavy infantry, did not at all dull the swords and spears; [4] the king's troops, with their line so widely extended, could not see the flanks even from the centre, much less one flank from the other, and the moisture had softened the bowstrings and slings and the thongs³ of the javelins. [5] The scythe-bearing chariots also, by which Antiochus had expected to cause panic in the hostile line, turned their terror upon their own men. [6] They were in general equipped in the following fashion: they had points along the pole, projecting like horns ten cubits from the yoke, with which to pierce whatever they encountered, and [7??] on the ends of the yokes there were two scythes standing out in two directions, one in line with the yoke, the other pointed downward towards the ground, the former to cut up whatever was near it on the sides, the latter to wound men who had fallen and came under the chariot; also from the hubs of the wheels on both sides two other scythes, pointing in different directions, were similarly fastened.⁴ [8] The chariots so equipped, because, if they were stationed on the flanks or in the centre, they would of necessity have been driven through their own ranks, had been posted by the king, as has been said, in the front rank. [9] When Eumenes saw this, being not unaware how uncertain was this sort of fighting and this kind of auxiliary, if one could frighten the horses rather than meet them in regular battle, he ordered the Cretan archers with the slingers and dart-throwers, with some [p. 413]troops of cavalry, not in mass-formation but as widely⁵ separated as possible, to rush out and shower weapons upon them from all sides at once. [10] This storm, as it were, partly by the wounds dealt by weapons hurled from all directions, partly by the discordant shouts, so frightened the horses that, as if they were set free from the reins, they rushed in every direction, not knowing where they were going; [11] their charges were easily avoided by the light infantry and the lightly-equipped slingers and the swift-footed Cretans; and the cavalry pursuing increased the confusion and fright of the horses and camels, these too being overcome with terror, while added to it all were the manifold cries of the throng of bystanders.⁶ So the chariots were driven away from the space between the two lines and, this idle show being ended, then at length the signal was given on both sides and the clash of regular battle began.