New Treatise on Military Efficiency, Volume 122: Defending the City

Assign either two or three men [to each battlement]. Their names must be written clearly upon the battlement wall original: 朶牆 (duoqiang); the parapets or crenellated sections of the wall providing cover for defenders.. They are to rotate their shifts every day and night.

Furthermore, for every hundred battlements—or every fifty—select one reliable and capable individual to serve as the Squad Leader, along with one assistant to aid him. original: 甲長 (jiazhang); this term refers to a head of a small administrative or paramilitary unit, usually chosen from the local "substantial" or well-to-do (yinshi) households to ensure accountability. They shall be dressed in blue clothing, and each must carry a waist sword and one signal flag.

As for the common laborers, each must prepare a uniform jacket original: 號衣 (haoyi); a simple surcoat or tabard used to identify personnel on a crowded battlefield., either in red or yellow. They are also required to have one long-handled spear or blade, as well as an iron axe; an iron hammer is also acceptable. If even one piece of this equipment is missing, the individual shall be bound and punished.

If there are surplus regular soldiers available, they should be deployed to reinforce strategic locations. original: 衝要 (chongyao); these are critical points of the fortification most likely to be targeted, such as gates, corners, or sections of the wall that are lower or easier to scale.

Establishing the Schedule

During periods when there is no urgent alarm, signals shall be sounded original: 吹打 (chuidia); literally "blowing and hitting," referring to the military music of horns, trumpets, and drums used for communication. every morning at dawn, at which point the city defenders may descend from the wall. Every evening, the signals shall be sounded again, and the defenders must ascend the wall to take their posts. On days when there are reports of enemy activity, the Drum Tower... The text likely continues on the next page regarding specific signaling protocols during an active siege.