Plutarch Antony 45

[1] On the following day they went forward under better protection; and the Parthians met with a great surprise when they attacked them. For they thought they were riding up for plunder and booty, not battle, and when they encountered many missiles and saw that the Romans were fresh and vigorous and eager for the fray, they were once more tired of the struggle.

[2] However, as the Romans were descending some steep hills, the Parthians attacked them and shot at them as they slowly moved along. Then the shield-bearers wheeled about, enclosing the lighter armed troops within their ranks, while they themselves dropped on one knee and held their shields out before them. The second rank held their shields out over the heads of the first, and the next rank likewise. The resulting appearance is very like that of a roof, ¹ affords a striking spectacle, and is the most effective of protections against arrows, which glide off from it.

[3] The Parthians, however, thinking that the Romans dropping on one knee was a sign of fatigue and exhaustion, laid aside their bows, grasped their spears by the middle and came to close quarters. But the Romans, with a full battle cry, suddenly sprang up, and thrusting with their javelins slew the foremost of the Parthians and put all the rest to rout. This happened also on the following days as the Romans, little by little, proceeded on their way.

[4]
  Famine also attacked the army, which could provide itself with little grain even by fighting, and was not well furnished with implements for grinding. These had been abandoned, for the most part, since some of the beasts of burden died, and the others had to carry the sick and wounded. It is said that one attic choenix ² of wheat brought fifty drachmas; and loaves of barley bread were sold for their weight in silver.

[5] Resorting, therefore, to vegetables and roots, they could find few to which they were accustomed, and were compelled to make trial of some never tasted before. Thus it was that they partook of an herb which produced madness, and then death. He who ate of it had no memory, and no thought for anything else than the one task of moving or turning every stone, as if he were accomplishing something of great importance.

[6] The plain was full of men stooping to the ground and digging around the stones or removing them; and finally they would vomit bile and die, since the only remedy, wine, was not to be had. Many perished thus, and the Parthians would not desist, and Antony, as we are told, would often cry: O the Ten Thousand! thereby expressing his admiration of Xenophon’s army, which made an even longer march to the sea from Babylon, and fought with many times as many enemies, and yet came off safe.