The Shouchenglu 守城錄 "On the defense of a city" is a military treatise written by the Southern Song period 南宋 (1127-1279) scholars Chen Gui 陳規 and Tang Shou 湯璹. The book is composed of three parts, namely Chen Gui's Jiankang chaoye yeqian houxu 靖康朝野僉言後序 and Shoucheng jiyao 守城機要, both 1 juan "scroll" long, and Tang Shou's 2 juan long Jianyan De'an shouyu lu 建炎德安守禦錄 "On the defense of De'an during the Jianyan reign (1127-1130)". The three parts were unified into one book during the reign of Emperor Ningzong 宋寧宗 (r. 1194-1224) and printed in this form. The three texts were written as the results of personal observations and experiences by the two authors. Chen Gui, for instance, describes firearms, a kind of hand cannon made of bamboo canes he had personally seen in use in 1132. This is the earliest mentioning of firearms in China.
Weapons and tools are described, as well as tactics to defend a city during a siege. Very essential for the beleaguered city is to make excursions and to attack the besieger's troops. For contemporary warfare it was necessary to modernize city gates, walls and moats. The towers at the corners of the city wall, for instance, should be equipped with artillery. The gates should be more simple and not be accompanied by secondary towers. Height and width of the city wall were also to be adapted to modern warfare, the moat was to be broader to impede the enemy from applying climbing tools or machines. Artillery, with or without the use of fire, was to be posed on the city wall from which the target could be fixed at better.
The earliest extant copies are a manuscript version from 1775, which provided the text in the collectaneum Siku quanshu 四庫全書, and two prints from the early 19th century.
Source: Huo Yinzhang 霍印章 (1989). "Shouchenglu 守城錄", in: Zhongguo da baike quanshu 中國大百科全書, Junshi 軍事, vol. 2, p. 936. Beijing/Shanghai: Zhongguo da baike quanshu chubanshe.