Treatise on Armament Technology, Volume 97

original: 武備志卷之九十七 — Wǔbèi Zhì Juǎn zhī Jiǔshíqī. The Wǔbèi Zhì is the most comprehensive military encyclopedia in Chinese history, compiled by Mao Yuanyi in 1621.

Plum Blossom Formation Diagram of the Miscellaneous Military Schools

original: 雜兵家梅花陣圖 — Zábīngjiā Méihuā Zhèn Tú

The Plum Blossom Formation (original: 梅花陣 — Méihuāzhèn) is a versatile tactical arrangement modeled after the five petals of a plum blossom. This "quincunx" layout—one unit in the center and four at the cardinal points—was favored for its symmetry and balance. It allows for a "circular" defense where the units can rotate or shift to support one another, ensuring that the formation has no "back" or vulnerable flank.

original: 前 — Qián

original: 右 — Yòu

original: 中 — Zhōng

original: 左 — Zuǒ

original: 後 — Hòu

In this diagram, the Miscellaneous Military Schools (original: 雜兵家 — Zábīngjiā)—the tactical theorists who blended various classical strategies—demonstrate how a force is divided into five modular groups. These labels do not just represent directions, but specific sub-commands within the army that must maintain their relative positions even while the entire formation is in motion.