Liber III, Pars III — Quomodo resistendum est munitioni factae per cuniculos, et qualiter machinis lapidariis, et aliis aedificiis obsessi debeant obviare. Cap. XXII.

Liber III, Pars III — Quomodo resistendum est munitioni factae per cuniculos, et qualiter machinis lapidariis, et aliis aedificiis obsessi debeant obviare. Cap. XXII.

Three specific methods for attacking besieged fortifications were outlined. One method was through tunnels and underground passages. Another method involved using stone-throwing machines. The third method was through buildings pushed up to the walls of the besieged castle or city. Therefore, if we have discussed how to invade the besiegers using the aforementioned methods, it remains to explain how the besieged can defend themselves against these attacks. First, we will discuss remedies against attacks through tunnels. We can identify two remedies regarding this matter. One remedy is to create deep ditches filled with water. If there are deep ditches filled with water around the besieged fortification, the attackers are hindered; so they can't assault the besieged through tunnels and underground passages. However, if the ditches are so deep that they can't be filled with water, they sufficiently hinder the underground passages; for this type of assault cannot breach the besieged fortifications unless those underground passages are deeper than the ditches. Therefore, the fortification must be defended either on solid rock above, or then, due to the hardness of the stones, it is not easy to conquer it through tunnels. Or it must be above easily collapsible rock, or above ground that can be easily dug; and then the fortification must be strengthened with deep ditches, so that it cannot be conquered through tunnels. The second remedy against tunnels and underground passages is to create another corresponding passage in the besieged fortification that matches the underground passage made by the attackers. For in our times, many of the besiegers have been in such peril; therefore, if this has happened before, we should not consider it impossible that it could happen again. The besieged should also have large containers filled with water or even urine near the entrance to the underground passage; and when they fight against the attackers, they should pretend to flee and exit that pit, so that they can pour all the accumulated water or urine over the attackers from the tunnels. For many of the besiegers have been in peril in our times; therefore, if this has happened before, we should not think it impossible that it could happen again. Now that we've seen how to resist attacks made through tunnels, we need to consider how those under siege should respond to assaults made by stone-throwing machines. However, there are four ways to counter these attacks. First, because sometimes a large group of armed men suddenly emerges from the besieged fortification and attacks the machine; and before the army can come to its aid, they can take it. But if the defenders do not dare to leave the fortification, then at night some men, bound with ropes, are sent out through the walls, carrying hidden fire without others noticing, to attack the machine; once this is done, they are pulled back up to the fortification. A third way to destroy machines is by making arrows, which they call bolts. This bolt is like a cage in the middle, where a strong fire made from oil, sulfur, pitch, and resin is placed; this fire, wrapped in a wick, was called incendiary by the ancient warriors. Such a bolt, launched from a strong ballista, often ignites the machine. Finally, another way to resist stone-throwing machines is by making other machines inside, striking them, and destroying them. Among other things, the best remedy is to create a foundation inside the machine using iron chains or a plate of iron, and to build a structure next to that machine where a large piece of iron can be well heated, which, when heated, can be placed on the iron foundation and thrown at another machine or any wooden structure. However, raw hides are not strong enough against this, and wood does not have resistance: for any wooden structure can be burned in this way. There are also many other specific precautions that are effective for defense against siege engines: but since such things do not fall completely under narration, they should be left to the judgment of the prudent. Now we need to explain how to resist against tunnels and stone-throwing machines; it remains to declare how to counter other structures that are pushed against the walls of the besieged fortification. To this end, anything that can be said against the resistance of machines would be valid. For just as stone-throwing machines can be destroyed by a sudden assault from the besiegers, and by men sent out secretly at night, and by an arrow carrying a strong fire, and by other machines throwing stones, or by pouring heated iron on them, so can wooden structures be attacked in all these ways. In fact, it has been proven that against each of these wooden structures, it is most effective to throw heated iron at them using other machines or in some other way. However, we can assign special remedies against such structures, so that a Wolf can be set against a Ram. It was said that a heavy iron beam striking the walls of a besieged fortress is called a ram due to the hardness of its head. To counter this, a certain curved iron with sharp teeth is constructed, bound with ropes, which captures the head of the ram or the head of that iron beam; once captured, either the ram is pulled upwards or it is suspended in such a way that it cannot harm the walls. Thus, ancient warriors called this kind of iron a Wolf, because it could capture a ram with its sharp teeth. However, against fortifications, heated iron is very effective; yet, there is a special remedy against them, because tunnels and underground passages are made, and the earth is secretly dug up from where the fortress should pass; once dug up, and the fortress submerged in it due to the weight, the fortress must be rebuilt, as it cannot be removed intact from the pit. Against vineyards, however, and also against small structures, heated iron is very effective. If, however, it should happen that the walls of the besieged fortress are pierced by such buildings: since there is doubt about this, before it happens, wooden structures should be erected next to those walls, or (if possible) stone walls should be built: so that if the attackers happen to enter the fortress, they may be kept enclosed between those walls; and unable to defend themselves due to being trapped by the walls, they may be buried under stones. It should be noted, however, that sometimes the attackers pretend to flee, and thus through ambushes and cunning, they invade the besieged fortress. Therefore, the fortifications should not be abandoned immediately after the enemy retreats, and the guard should not be neglected. Rather, the conditions of the enemy must be investigated, so that what they could not openly possess, they cannot obtain through ambushes and cunning.