Wubizhi Volume 82

Drill Practice for Chariots and Vehicles, Part 6

When the battalions original: 哨 Shao and the Command Staff original: 中軍 Zhongjun combine, they form the outer camp. When four battalions set up camp, the Left and Right divisions of each unit form the outer layer, while their respective Command Staffs form the inner layer original: 子層 Ziceng; literally "child-layer," referring to a nested defensive circle.

If five battalions set up camp, the outer four units follow the same layout as the four-battalion model to form the exterior. The inner circle consists of two layers: the command staff forms the second layer, and the Central Battalion original: 中哨 Zhongshao forms the third, innermost layer. This formation constitutes a camp of fifteen thousand soldiers and is known as a "Small City" original: 小城 Xiaocheng.

Upon the striking of the gong, all soldiers dismount. The troops of the outer camp must tether their horses together according to the established drill. Simultaneously, Crouching Tiger cannons original: 虎蹲礮 Hudunpao; a light, mobile mortar stabilized by support legs, shaped like a crouching tiger and other artillery pieces are positioned in the open spaces in front of the unit flags.

The troops must listen for the rhythmic beating of the drums. Those carrying firearms original: 火器 Huoqi shall march forward on foot, stopping approximately ten paces in front of the horses. When the hand-gong sounds, the drumming ceases.

The gunners must be organized in advance: within every five-man squad original: 伍 Wu, three men are designated as a firing section original: 班 Ban. The second squad becomes the second section, and the third squad becomes the third section.

When it is estimated that the enemy has reached a distance of fifty paces approximately 75–80 meters, the Command Staff fires a single signal cannon. The trumpets original: 喇叭 Laba then sound a "sky-piercing" blast. As soon as the trumpet blast concludes, the first squad fires its cannons in unison. From this point forward, the Command Staff does not fire any more signal cannons, and the trumpets sound the high blast again this signal likely prompts the next squad in the rotation to fire.