For in the battle the left wing under Parmenio was thrown back and in distress, when the Bactrian cavalry fell upon the Macedonians with great impetuosity and violence, and when Mazaeus sent horsemen round outside the line of battle to attack those who were guarding the Macedonian baggage. Therefore, too, Parmenio, much disturbed by both occurrences, sent messengers to Alexander telling him that camp and baggage were gone, unless he speedily sent strong reinforcements from front to rear
Edition :
Plutarch. Plutarch's Lives. with an English Translation by. Bernadotte Perrin. Cambridge, MA. Harvard University Press. London. William Heinemann Ltd. 1919. 7.