Late Ming sea owl

Chapter 260: Vauban Siege Methods

The second parallel trench was dug at 3:00 p.m. on the second day after the massacre, which means that the excavation of the eight diagonal communication trenches took nearly a day and a night.

In terms of total length, the eight diagonal trenches combined are only about one and a half times the length of the first parallel trench, but the total time taken is more than twice as long.

This is because Zheng's army began shelling while digging the diagonal trench. Although the efficiency was not high due to the angle of the trench, it still caused great trouble to the trench construction work.

With each step forward in the trench, the threat from the artillery fire on the city walls would increase exponentially. Fortunately, Xiamen City was not a bastion, and the power of the artillery on the city walls was not strong enough. So far, only a dozen prisoners of war who were repairing the trenches had died, and a supervisor with a bird gun was seriously injured.

Of course, the Huiyou Company did not just take the beating without fighting back. The seven-jin cannons in the twenty artillery batteries continued to fire at the city walls in order to disperse the enemy's firepower.

The gunners of the Navy took turns to fight, and the battle was very difficult. Compared with the artillery of the Zheng army, these seven-jin cannons had limited power advantages, and the temporary simple artillery forts were not very strong. In addition, the gunners of the Zheng army had the advantage of being on high ground.

Despite this, a small part of the battlements of Xiamen's east city wall was destroyed, and more than 20 pirates on the city wall were killed. The Huiyou Company still had a slight advantage in the artillery duel, which could only be attributed to the gunners' artillery skills.

Soon after the second parallel trench was dug, Zheng Zhilong called Wang Mengxiong to the tower of Qiming Gate. Seeing that he would have to leave the city for a decisive battle tomorrow after the sword was put down tonight, the 23-year-old Minhai bandit hesitated again.

Zheng Zhilong pointed outside the city and said to his brother, "I don't think this trench is used to besiege the city. It seems to be used to cover the enemy troops approaching the city wall. Do you think that Lin is still planning to attack by force?"

"What the boss said seems to make some sense. Bandit Lin's tactics are so imaginative and unconventional. I may have misjudged him..."

Wang Mengxiong had to admit that his judgment was wrong. Lin Hai did not try to surround the city with trenches, but instead used the diagonal trenches to advance towards the city walls. This tactic was something he had never heard of.

This is certainly not because Wang Mengxiong is ignorant. This Z-shaped trench siege tactic did not appear until nearly half a century later in Western Europe. It is generally called the Vauban siege method or trench siege system, which was mainly used to counter the increasingly difficult to conquer bastions.

The person who summed up this set of tactics was a Frenchman named Sebastien Le Prestre de Vauban. He was the most famous military engineer in the artillery era and the culmination of the bastion fortification system after more than a hundred years of evolution. After all, only those who understand shields best can design the best spears.

The Vauban siege method was originally a combination of siege and siege. Generally speaking, the first parallel trench would surround the enemy city, and then several attack directions would be selected based on the weaknesses of the opponent's defense system, and then the artillery positions would be pushed forward in the attack direction through Z-shaped trenches.

However, Lin Hai had no plans for a long-term siege. He was eager for Zheng Zhilong to come out of the city for a decisive battle, so he only used part of the Vauban siege tactics, which made Zheng and Wang see through his intentions.

"How do you think Lin the bandit will attack? Will he just keep digging trenches all the way to the foot of the city wall?" Zheng Zhilong asked.

"This... I dare not say for sure..." Wang Mengxiong did not dare to speak too confidently this time. He continued, "But I think it won't happen. The further you dig the trench, the more dangerous it will be. After a hundred steps, even a bird gun can kill people. It's better to rush over directly than to dig the trench with great effort."

"Zheng thought so too. This zigzag trench is mainly for artillery defense. It is meaningless to dig too close. The cannons on the city walls can't reach that close..." Zheng Zhilong was talking about the depression angle of the city defense artillery. In fact, if the attackers rushed to the base of the city wall, even the muskets and bows and arrows would have no range of fire. The only useful weapons are throwing weapons. This is also the reason why the digging corner tactic can exist. The Later Jin Dynasty once relied heavily on this siege tactic.

"If the thief Lin is really planning to attack by force, I, Zheng, would like to postpone leaving the city for the decisive battle and first dampen the thief Lin's fighting spirit in the battle to defend the city." Zheng Zhilong went on to say, while looking at Wang Mengxiong with an inquiring look.

"I think it's okay..."

Wang Mengxiong just agreed, but Zheng Zhilong said: "I am afraid that Lin will push the cannons too close, first destroy the city wall and then attack. In that case, our army will be self-defeating and the morale that has been boosted with great difficulty will collapse again."

"That's impossible. What kind of cannon can bring down a city wall? The cannons that Lin Bandit used were used to attack the battlements. Their purpose was to blast the city wall bare and reduce casualties among the attackers."

"You may not understand that those under the city are not Lin Bandit's largest cannons. He also has cannons weighing several thousand pounds."

"Forget thousands of pounds, even tens of thousands of pounds will be useless. The most we can do is knock down the corner tower. Do you want to break down the city wall? No way." Wang Mengxiong was very confident this time. He didn't believe that the power of the artillery could be that great.

This is not blind confidence, as Chinese city walls are indeed difficult to knock down with artillery fire. Unlike the traditional European straight stone city walls, the main body of Chinese city walls is made of rammed earth that is wide at the bottom and narrow at the top, and some are covered with bricks on the outside.

Rammed earth can absorb kinetic energy better than stone, and the gravity dam structure, which is wide at the bottom and narrow at the top, is not easy to collapse. In contrast, the high and thin stone walls in Europe can be crushed by their own weight as long as a large hole is drilled at the bottom.

This is why Europe came up with bastion technology more than a hundred years ago. The actual bastion system also used a gravity dam structure, and most of the city walls were built with rammed earth. However, European geometry was indeed far ahead of the East. The design of the bastion also eliminated blind spots for shooting and maximized the advantages of crossfire, which was much more advanced than the Eastern horse-faced gun.

However, Eastern city-building science did not stand still in the artillery age. Looking at the city wall structure over the past 5,000 years, the city walls in the cold weapon era were built higher and higher, reaching their peak in the Tang and Song dynasties.

In the era of hot weapons, the city walls went from being built higher and higher to being built thicker and thicker. In the Ming Dynasty, many city walls were only two meters high, but the thickness at the bottom was four meters. In addition, the shape of the battlements was also optimized compared to the Tang and Song dynasties.

The height of Xiamen's city wall without the battlements is 22 feet, with urn walls at all four gates and turrets at all four corners. The urn walls and turrets are like horse-faced forts, and can also exert crossfire to a certain extent, but they are not as completely effective as bastions in eliminating blind spots.

In addition, there is a deep enough moat around the city wall, which together with the city wall forms a three-dimensional city defense system. All these give Wang Mengxiong the confidence to defend the city.

"In that case, let's hold off on leaving the city for the final battle. Let Lin the bandit suffer enough under the city wall first!"

Zheng Zhilong said it very firmly, but the uneasiness in his heart had not dissipated. He didn't know whether the reason for making this decision was to delay it for a day or two.

(End of this chapter)