Shouchenglu 守城錄 "On the defence of a city" is a military treatise written during the Southern Song period 南宋 (1127-1279) by Chen Gui 陳規 xxx and Tang Shou 湯璹 xxx. 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 with a length of 1 juan, and Tang Shou's 2 juan-long Jianyan De'an shouyu lu 建炎德安守禦錄 "On the defence of De'an during the Jianyan reign-period (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 was to make excursions and to attack the besieger's troops. For contemporary warfare it was necessary to rebuild city gates, walls and moats to make them stronger. The towers at the corners of the city wall, for instance, should be equipped with light 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, and 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 better.