Miscellaneous Defenses
Qin Guli asked: "The enemy are numerous and fierce; they deliberately display their might to intimidate us. They bring firewood and earth together to pile up ramps (yangqian), building earthen platforms that tower over our troops and civilians. Advancing under cover of large shields, they press directly against the city walls, while weapons and crossbows fire simultaneously. What should be done about this?" Mozi replied: "Are you asking about the method of defending against ramps? The ramp is a relatively clumsy tactic among siege methods; it is enough to tire the soldiers but insufficient to harm the city. The method for countering ramps is this: if the enemy attacks from a distance, defend from a distance; if they approach the walls, defend at close quarters, preventing them from reaching the walls. Arrows and stones are shot without cease, firing rapidly left and right. Use lan wood as posts for support, and set up watchtowers to stabilize the defense. Inspire our elite soldiers, being careful not to let them look back; the defenders must strike down heavily, while the attackers withdraw lightly. Foster a brave and high-spirited morale, so the people’s hearts are a hundred times strengthened; capture many enemies and reward them repeatedly, and the soldiers will not grow lax. If the enemy continues their earthworks and cannot be stopped, allowing them to approach the walls, then counter them with the methods used against scaling ladders. In all cases of defending against smoke, battering rams, scaling ladders, and siege towers, the walls must be widened to defend. If time is insufficient, reinforce the walls with timber. For a hundred paces to the left and a hundred paces to the right, densely rain down arrows, stones, sand, and ash, supplemented by firewood and boiling water. Select elite troops, being careful not to let them look back; enforce strict rewards and punishments, prioritizing calmness, then follow with swift action; do not let them harbor doubts, inspire their fierce anger, and the people’s hearts will be a hundred times strengthened; capture many enemies and reward them repeatedly, and the soldiers will not grow lax. Battering rams, siege towers, and scaling ladders are all struck with battering rams. The qu (a defensive screen) is one zhang and five chi long, with three chi buried underground; the arrow (projectile) is one zhang and two chi long. The qu is one zhang and six chi wide; its ladder is one zhang and two chi long; the qu hangs down four chi; the erected qu should not have leaves attached for five cun. The ladder-qu is placed every ten zhang. The approximate number of ladder-qu and da (shields) is 258 qu and 129 da per li. All roads outside the city can be fortified at strategic points to block the enemy; at especially critical places, build three watchtowers arranged in a triangular pattern like the stars of the Weaver Girl, so they can support each other. All large mounds, forests, ditches, hills, field paths, outer city gates, and alleyways can be fortified at strategic points, and set up secret signals to scout and know the number of comings and goings and where the enemy hides.
To protect the populace, first count the official buildings, private houses, and rooms in the city, and assign shelter according to size. Among those being protected, if someone wishes to follow brothers, friends, or acquaintances, it may be permitted. Grain, livestock, goods, and all items from houses outside the city that can aid in defense should be brought into the city; when matters are urgent, have them piled up inside the city gates.
Scouts should not exceed fifty men; when the enemy arrives, they withdraw following signals (ye), only hiding in critical situations.
When the people contribute grain, cloth, coins, cattle, horses, and other livestock, set fair prices for them, give them certificates, and record everything. Enable everyone to use their strengths, and all under heaven will be well-managed; balance their duties, and all under heaven will be well-ordered; let them do what they enjoy, and all under heaven will be complete; assign the strong and weak their proper roles, and all under heaven will be perfect.
Build postal watchtowers in a circular shape, over three zhang high, with stairs built obliquely as removable ladders; the handrails on either side of the ladder are three chi long, and the connections at the door are three chi, fastened with ropes. Lay planks alternately to construct a drawbridge. Set up deaf-stoves (long zao?), with one drum per watchtower. Enemy beacons, alarm beacons, and confusion beacons are relayed in sequence to respond, until reaching the main city. When matters are urgent, raise or lower (the beacon). After the beacon is lit, beat the drum five times to transmit, then use fire to relay, reporting the direction of the enemy’s approach and their numbers, returning before dawn. If the enemy comes or goes continuously, the beacon should not stop. When the enemy is sighted, light one beacon; when they enter the border, light two beacons; when they approach the outer wall (she qi?), light three beacons and beat the drum once; when they reach the outer city gate, light four beacons and beat the drum twice; when they reach the inner city, light five beacons and beat the drum five times. At night, use fire according to this count. The beacon keepers, when matters are urgent, go out at dusk and have them all set secret signals. Large mounds and forests should be made scourable; scout at dawn, and if there are no traces, set up markers, with the city responding. Scouts go out and set up field markers; the scouts (chi hou) sit inside and outside the city walls, erect flags, with half the soldiers inside the city, so the enemy cannot know their numbers. If there is an alarm, raise the kong marker; when the enemy is sighted, raise the mu marker. On the city, use flags to direct; the scouts beat the drum to march, organize the flags for battle, and follow the flag commands. Men in the fields carry combat gear and follow the scouts; women quickly run into the city; upon seeing the signal, relay it until it reaches the city. Three men guard the markers, rotating to erect them and watch. The defenders repeatedly order cavalry or officials to patrol the surroundings, thereby knowing the enemy’s situation. Each group (cao) beats the drum once; when the enemy is sighted, beat the drum, relaying until it reaches the city.
One meal per day (sheng shi): 36 shi per year; three meals per day (can shi): 24 shi per year; four meals per day (si shi): 18 shi per year; five meals per day (wu shi): 14 shi and 4 dou per year; six meals per day (liu shi): 12 shi per year. One meal per day is 5 sheng per meal; three meals per day is 3 and 1/3 sheng per meal; four meals per day is 2.5 sheng per meal; five meals per day is 2 sheng per meal; six meals per day is 1 and 2/3 sheng per meal; eat two meals per day. During the period of famine relief, eat 2 sheng per day for 20 days, 3 sheng per day for 30 days, and 4 sheng per day for 40 days; thus the people can survive a 90-day grain limit.
When the enemy approaches, quickly collect metal implements from the villages, such as copper and iron, and other items that can aid in defense. First, count the county officials’ houses and government buildings for non-urgent items, noting the size, length, and total quantity of materials, and requisition them urgently when needed. When the enemy is near, dismantle houses and cut down trees; even if someone requests otherwise, do not comply. Bring in firewood but do not pile it in fish-scale patterns; place it on the roadside so it is easy to access. Timber that cannot be fully brought into the city should be burned, so the enemy cannot use it. When piling timber, sort it by length, size, and quality; on all four sides outside the city, pile it inside the city walls; all large timber should have rings (guan bi) made and then be stacked.
Officials ranked above Cheng Shou Sima must have their parents, brothers, wives, and children held as hostages by the ruler before they can take up their posts. Appoint Du Sikong: four for a large city, two for hou. County hou: one per side. Ting Wei and Ci Sikong: one per ting. Officials serving at the defense posts must be of sufficient means, incorruptible, and trustworthy, with parents, brothers, wives, and children in protected palaces, before they can serve as shi li. All officials must have hostages before they can assume their duties. Two men guard the main gate, standing on either side of the door, allowing pedestrians to pass quickly from outside. Each holds four ji (halberds), standing by the door, and these men sit under the ji; officials inspect them five times daily, reporting the names of any who flee.
At strategic points along the outer bank of the moat, set up dummy figures, and have night patrols shoot at them, to deal with any negligent individuals. In the water outside the wall, set bamboo arrows; the arrows are placed every chi for a width of two bu, inserted five cun below the water, mixing lengths; the outer bank has three rows, with the outer ones facing outward and the inner ones facing inward. Every thirty bu, set up a crossbow hut (nu lu); the hut is ten chi wide and one zhang and two chi long. Every one hundred bu, station a squad; if one squad faces an emergency, urgently dispatch a nearby squad to assist, with the next squad taking their place.
When using tallies for entry and exit during city defense, the officer in charge of the tallies must write detailed records, noting the circumstances, comparable to that matter, and await the return report to verify with a sword. When a tally is issued, the person being let out must report the name of the one holding the tally.
The watchtowers connect to the officers' quarters, intersecting and interpenetrating the rooms. Build covered passageways, construct walls, and finish the tops of the walls well.
Gather vegetables, ensuring that households have three years' worth of vegetable reserves to guard against floods, droughts, and irregular harvests. Have border counties pre-plant and store yuanhua (Daphne genkwa), yuncao (a type of grass), wutou (Aconitum), and qiuye (Catalpa leaves). Ditches and wells in dwellings outside the city may be filled; if they cannot be filled, place these items inside them.
In times of stability, display danger; in times of danger, display stability.
When the enemy arrives, all doors and gates must be chiseled into similar hole-like shapes, each made in two forms: one chiseled with a rope attached, the rope four feet long and as thick as a finger.
When the enemy arrives, first slaughter cattle, sheep, chickens, dogs, wild ducks, geese, and pigs. Skin them all and collect their hides, sinews, horns, fat, feathers, and quills.
Officials use jia wood (Catalpa) and tong wood (Paulownia) as materials, make iron arrowheads, thick bamboo slips as crossbar supports. In urgent times when haste prevents long-distance travel, order the felling of trees in dwellings outside the city, estimate the quantity, and construct attack equipment as if repairing the city walls, doing so on three sides, with items weighing over five jin. All timber submerged in water should not exceed one raft. Plaster thatched roofs or piled firewood with mud to a thickness of over five cun.
Officials each report the material goods within their jurisdiction that can assist in defense preparations, and submit them.
There are slanderers, the beneficial, the malevolent, the virtuous, the noble, strategists, warriors, skilled artisans, envoys, insiders, outsiders, the good, and those skilled in guarding gates. The defender must examine the reasons why they are so, accepting them only if their name matches their reality. If the people mutually hate each other, or discuss the officials, the content of the officials' defenses must be written on wooden slips and stored, awaiting the arrival of the accuser for cross-verification. Those under five chi in height who cannot immediately serve are appointed as clerks, serving in government offices or lodgings.
Thunder stones and sharp arrows, all materials and equipment must be carefully deployed, each with a set quantity in reserve. Make siege carts using tai wood (a type of wood), use light carts on the city walls, with wheels and hubs ten chi wide, shafts one zhang long, make three spokes, six chi wide. Make plank boxes, with length matching the shafts, four chi high, with a covered top, and arrange the interior so it can hold arrows.
Mozi said: "In total, there are five situations in which defense is impossible: the city is large but the defenders are few—this is the first impossibility. The city is small but the defenders are many—this is the second impossibility. The population is large but grain is scarce—this is the third impossibility. The market is far from the city—this is the fourth impossibility. Stored supplies are outside the city, and the wealthy are outside the city—this is the fifth impossibility. In general, with ten thousand households, the city should be three li square."