Aeneas Tacticus 38.1-2, 38.4-5: how to deal with the troops during an attack.

1. At times when assaults are being made on the wall either by machines or by actual storming parties, the fighting force of the city should be divided into three parts, so that there may always be one part in action, another off duty, and the third preparing for action: thus the troops will always be fresh. 2. A larger detachment of picked troops should go all round the walls with the general, relieving any part of the fighting force which is hard pressed. For the enemy are more afraid of a foe whose attack they know to be imminent than of one with whom they are actually engaged.

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4. During the fight you should encourage the men on the wall with tact and discrimination: give a word of praise to those who deserve it; make a special appeal to those who need it. Do not lose your temper with any of the rank and file: it will only dishearten them; if a reproof for negligence and insubordination is necessary, 5. single out the most wealthy and influential citizens; then it will serve as a warning to the others as well. The occasions on which these various offences should be passed over are mentioned in my manual on Addressing Troops.