Zosimus, New History 1.53

Zosimus (Greek Ζώσιμος): Early Byzantine, pagan author of a history of the Roman Empire, published in the first quarter of the sixth century CE.

The translation of ZosimusNew History offered here was printed in 1814 by W. Green and T. Chaplin in London, and was probably prepared by J. Davis of the Military Chronicle and Military Classics Office. The translator is anonymous. The text was found at Tertullian.org. The notes were added by Jona Lendering.

[1.53.1] At the commencement of the engagement, the Roman cavalry receded, lest the Palmyrenes, who exceeded them in number, and were better horsemen, should by some stratagem surround the Roman army. But the Palmyrene cavalry pursued them so fiercely, though their ranks were broken, that the event was quite contrary to the expectation of the Roman cavalry. For they were pursued by an enemy much their superior in strength,

[1.53.2] and therefore most of them fell. The foot had to bear the brunt of the action. Observing that the Palmyrenes had broken their ranks when the horse commenced their pursuit, they wheeled about, and attacked them while they were scattered and out of order. Upon which many were killed, because the one side fought with the usual weapons, while those of Palestine brought clubs and staves against coats of mail made of iron and brass. 

[1.53.3] The Palmyrenes therefore ran away with the utmost precipitation, and in their flight trod each other to pieces, as if the enemy did not make sufficient slaughter; the field was filled with dead men and horses, whilst the few that could escape took refuge in the city.