History of the Peloponnesian War

Thus on the side of the Athenians some were even now being defeated, and others coming up unconquered for their first attack. A large part, too, of the rest of their forces had only just ascended, and others were still ascending; so that they did not know on what point to advance. For in consequence of the rout which had taken place, every thing in front was now in confusion, and it was difficult to distinguish orders through the uproar.

For the Syracusans and their allies, on gaining the advantage, were cheering each other with no little shouting, (it being impossible during the night to express themselves in any other way,) and at the same time were receiving the charge of their assailants: and the Athenians were in search of one another, and thought that whoever met them was a foe, even though he might be a friend, belonging to those who were now flying back. And by their frequently asking for the watchword, because they could not by any other means distinguish them, they both caused great confusion on their own side by all asking at once, and made it known to the enemy;