In order to prevent tunnel attacks, people in the city usually dig a deep ditch around the city and introduce water, which can effectively prevent the enemy from digging tunnels. Cave attack is to dig tunnels and destroy cities. The technology of point attack and anti-point attack is the same, but the latter is more complicated.
"Mozi prepares the cave" records the method of anti-cave attack in detail: set up a lookout at the height of the city to closely monitor the enemy's movements. Once you find signs of tunneling such as abnormal accumulation of earthwork and turbid water flow, immediately dig wells in the corresponding direction of the city near the wall root.
Five-step well or three-foot well, put a new clay pot at the bottom of the well and cover it with thin cowhide for people with sensitive hearing to listen to. When the enemy digs a tunnel, the sound travels very fast in the underground, with little attenuation, which is easy to cause the resonance of the cylinder, so the direction of the tunnel can be detected by this method.
Anti-point attack technology
Mozi? "Prepare the Cave" says: When drawing the enemy, prepare a "continuous version", that is, a large board made of wood strips, the height and width of which are consistent with the tunnel to stop the smoke; Dig holes in the board to make the spear shoot outward and prevent the enemy from blocking the smoke pipe; If the enemy blocks the smoke pipe, cut the smoke pipe behind the board and then quickly lead the board back. It is conceivable that the confrontation in the tunnel is also quite fierce.
Cave attack and counter-cave attack technology are closely related to the developed mining technology in Shang and Zhou Dynasties. Digging a siege tunnel or an anti-tunnel is the technology of tunneling. Archaeological excavation of the Shang and Zhou copper mine site in Tongling, Ruichang, Jiangxi Province shows that during the Shang and Zhou dynasties, there were many kinds of tunnel excavation forms, such as vertical shaft, drift, inclined lane and trough pit, which were used in combination with life and residence.