Individual spacing and formation frontage
Generally speaking, four typical Chinese soldier would occupy a five chi (approx. 5.35 feet or 1.63 m) by five chi square. In other word, space between two soldiers, measured from shoulder to shoulder, is roughly 2.1 feet. For example, an early Mandarin Duck squad employed by Qi Ji Guang (戚繼光) would occupy a rectangular space of five chi wide and one zhang five chi long (5.35 feet × 16.05 feet).
Ming period military theorists preferred this spacing probably due to the significance of number five in Chinese culture (Five Elements, Five Classics, five appendages, etc.) more than anything else, although it did serve a more practical purpose — five chi was a good spacing for fighting in narrow, maze-like trails, footpaths and paddy field ridges, all common geographical features of South China, as it maintained a fine balance between formation density, maneuverability, and situational awareness. A battle in such terrain required an army to be able to quickly disperse into numerous small units and occupy as many trails as possible. At the same time, individual small units must maintain coherence without losing contact with each other, while checking for potential ambush (hence the emphasis on small unit tactics in Ming infantry doctrine). Once the fighting took place, occupied trails could be used for reinforcement, flanking maneuver, ambush and counter ambush (whilst preventing the enemy from doing the same).
A densely packed and relatively inflexible formation would find it extremely difficult, if not outright impossible, to maneuver such terrain, while a loose skirmishing formation would be quickly overpowered by the combined arms of Mandarin Duck squad.
Modern double file formation and hallway saturation tactic used by special ops can be seen as the contemporary application of similar concept.
|Aerial photo of paddy fields during harvest time. Zhejiang, China.|
Other spacing were also used. Xu Guang Qi (徐光啟) for example chose four chi, five chi and six chi spacing for some of his formations.
Gaps in the formation
Like ancient Romans, many Ming armies employed gaps in the formation, albeit on a much smaller scale. Instead of using large gaps equal to the width of entire maniple of legionaries (hundreds of men) like the Romans, Chinese armies utilised small gaps of approximately one zhang wide (approx. 10.5 feet) that could only accommodate five to twenty men. Nevertheless, the purpose of maintaining such gaps were essentially the same — to facilitate unit rotation.
While Chinese had faced many different enemies, both trained armies, savage hordes and undisciplined mobs, the risk of enemy troops penetrating into the gaps never seems to occur to most Chinese military thinkers. In other word, they never thought of these gaps as potential weak points. It is possible that these gaps were simply too narrow to be exploited, or generally consisted of untraversable terrains such as flooded paddy field patches.
Besides, many Chinese armies often made area denial weapons such as caltrops and cheval de frise standard issue (for example, Qi Ji Guang's army had six cheval de frise and ninety caltrops for every twelve men, in addition to one cloth wall). Presumably, these area denial weapons could be deployed quickly to punish any enemy foolish enough to attempt to penetrate into the gaps.
Default to Hollow Square
|A hollow infantry square formed by eighty-eight Mandarin Duck squads, or 880 troops (not counting porters, reserve force and commanding officers positioned at the centre). From 'Lian Bing Za Ji (《練兵雜紀》)'.|
Chinese armies utilised both large, regiment-sized square as well as multiple smaller squares working in tandem with each other. However, Chinese squares were relatively immobile and generally ill-suited for offensive role (unlike later Napoleonic squares).
|Example of a fortified camp, from second edition 'Ji Xiao Xin Shu (《紀效新書》)'.|
Whenever time and resource permit, Chinese armies would construct incredibly fortified military camps known as Cheng Ying (城營, fortress camp) complete with multiple layers of wooden and earthen walls, watchtowers, trenches, ditches, abatisses and punji pits, as well as defensive trebuchets and hundreds of crossbow traps. If building such sophisticated camp was not possible, they would opt for simpler palisade fencing and ditches. For truly simple camps or fortified positions that could be build hastily, Bu Cheng (布城), cheval de frise, caltrops and anti-cavalry trip ropes were used instead.