Under the Helan Mountain, there are formations like clouds, and you can hear feathers flying across the sky day and night.
The envoy Sanhe recruited young men, and issued an edict to send out generals from the Five Ways.
Try to brush your iron clothes like snow, and talk about holding a sword to move the stars.
I wish I could have Yan's bow to shoot at the general, and I would be ashamed to have Yue Jia call my king.
Don't be afraid of the old days of guarding in the clouds, you can still win meritorious deeds in a single battle.
——Excerpt from "The Journey of a Veteran" by Wang Wei of the Tang Dynasty
…
Zhou Zhi, the puppet prime minister of Yan, once again assembled his army and attacked Beicheng. Li Guangbi immediately led the main force into Beicheng. Li Fei Yuanli gave Bai Fu five hundred elite swordsmen to follow Li Guangbi into Beicheng.
Li Guangbi climbed up the tower and looked at the Yan army's formation.
Li Guangbi took out his command arrows, assigned defensive tasks, and the generals took the order and left.
Li Guangbi asked Bai Fu's Modao Army to rest for a while and serve as a reserve team, ready to support the generals at any time.
Although Bai Fu was fighting, he was not tired at all. He took the opportunity to carefully observe the city structure of Heyang North City.
At the time of Lihentian, Master Zhongsi once explained the structure of the city in detail using the examples of the ten great passes of the Tang Dynasty, one of which was the Three Cities of Heyang.
Among the three cities in Heyang, the North City was designed by Master Zhongsi himself.
Beicheng is the strongest of the three cities in Heyang, so Li Guangbi stationed the main force of Shuofang's army here.
Outside the city, there was originally a moat that surrounded the entire city. The river was deep and long, and there was only a suspension bridge across the river at the city gate for passage.
Bamboo sticks and antler trees were placed at the bottom of the moat. If you fell into the river or tried to swim across the river, you would either die or be injured.
However, the Yan army besieged the city for many days, cut off the moat, and filled it with earth and sandbags.
This defensive barrier has been lost. Therefore, the Yan army dared to covet Beicheng today.
Most of the city walls in Tangzhou County are built with rammed earth, while Heyang North City is a city built with granite and blue bricks. The specifications of the city bricks are quite uniform, and they are bonded with a mortar mixed with lime, glutinous rice slurry and tung oil.
Extraordinarily strong.
Heyang City Wall covers a large area, and the city has blind spots for defense.
In order to effectively monitor and defend the enemy from attacking the city, when Master Tadatsuki designed the city, he built protruding corner pillar-shaped towers - "horse faces" - at intervals and at the corners of the city wall.
The "horse face" protrudes from the tower outside the wall, and is drilled with shooting holes to facilitate crossbowmen to attack the enemy from the front.
A platform called a "war shed" was built on the "horse face" to accommodate more soldiers and defensive equipment, and it could also be used as a beacon tower.
Except for the north city wall, there is also a curved arrow tower at the corner of the city wall, called the "Tuan Tower". Its structure and function are similar to the horse face.
With the combination of "horse face" and "tuan building", there is no defensive blind spot in the entire northern city wall.
Outside the north city gate is a semicircular urn city. If the rebels want to attack the city, they must first break through the urn city. But after entering the urn city, the rebels stuck between the urn city and the city gate will become the best arrows for the crossbowmen.
target.
Even though there is a dangerous barrier like Wengcheng outside the city gate, the city gate in Heyang Beicheng is still unique in its design.
There is an L-shaped protective wall in front of the North City Gate to cover the originally exposed city gate.
Master Zhongsi told Bai Fu not to underestimate this protective wall.
With this curved protective wall, in addition to using the added twists and turns on the route into the city to screen people entering and leaving, it also increases the defensive effect by reducing the space in front of the city gate that can be used for force application.
Even if the enemy's siege equipment such as rams and vehicles rushes to the door, they will be unable to take action due to lack of space, limiting the impact strength of the siege ram, and will eventually fail.
The gate of the North City is a double iron-clad wooden door. It is not easy to break through and drive straight in.
There is a trench in the walkway of the city gate. Inside the trench is a "thousand catty gate" made of giant stones. It is usually pulled up and suspended by a pulley and winch. Once the enemy invades, the "thousand catty gate" will drop quickly.
Cut off the retreat route, send out ambushes in all directions, separate the enemies inside and outside the city, and annihilate them separately.
The entire city gate and urn city have a dozen caves for hiding soldiers, which can accommodate two thousand troops for garrison.
There are ramps on the left and right sides inside the city gate for riding horses to climb the tower.
Bai Fu looked around and couldn't help but sigh. Master Zhongsi was indeed a famous general with both civil and military skills. He was not only good at fighting, but the Heyang North City he designed was also well-deserved. No wonder it was called the first important city to guard the transportation between the north and the south.
Bai Fu finally understood the reason why Li Guangbi would rather abandon Luoyang, the eastern capital, and garrison Heyang.
Not only is the city strong and dangerous, easy to defend but difficult to attack, it is also protected by the heroic soul of General Zhongsi!
…
Zhou Zhi, the puppet prime minister of Yan, led a group of marching commanders and stood in the chariot to look at the northern city of Heyang.
The nest car is located on a large eight-wheeled trolley. Two strong long poles are erected on the chassis of the carriage. The top of the long poles is a cross beam. There are rotating axes at both ends of the cross beam and a rope in the center. The ropes of the cross beam are connected with the ropes on the chassis of the carriage.
The windlass is connected.
Similar to the principle of using a bucket to draw water from a well, a box-shaped wooden house can be hoisted with a hemp rope and raised to the top of the pole by winding or unwinding the wire.
Because the hut hanging on the top of the pole resembles a bird's nest, it is called "nest cart", also known as "lou cart", "linche" or "watchtower cart". It is used for attackers to climb the tower and look into the distance, and to look out at the defenders.
military situation.
Zhou Zhi and the marching commanders carefully surveyed the city structure of Heyang North City and believed that it would be very difficult to attack Wengcheng by using rams, boxcars, etc. and directly break through the North City from the city gate.
For the current plan, we can only rely on giant siege equipment such as ladders, towers, and parapets to break through the city wall.
After the siege strategy was decided, the Yan army's drums and cannons were blasted, and the horns of the horns were blasted.
The soldiers of the Tang army were refreshed and knew that the Yan army was about to launch an attack.
The Yan army dispatched large-scale siege equipment - ladders and troughs.
Thousands of soldiers pushed dozens of ladders and troughs slowly towards the city wall. The dozens of ladders and troughs were like dozens of giant beasts, with ferocious faces, which frightened the soldiers guarding the city.
The ladder is huge, as high as the city wall, and is indestructible. The middle layer of the ladder is a siege tower, which can accommodate 200 elite soldiers. The top is an arrow tower and a springboard.
There are wooden wheels at the bottom of the ladder. Soldiers can hide behind the bunker of the ladder and push the ladder towards the city wall.
…
The floor trough, also known as the "well railing", is about ten feet high. It is similar to a wooden movable arrow tower. It is made of strong bamboo wood and then erected or pushed to the city wall. The crossbowmen mounted on it can condescendingly descend from
Shoot arrows from high places to shoot at the defenders.
The trough is divided into several floors. In addition to archery and stone throwing, there are also springboards that can be used to build the city wall after approaching, allowing soldiers to directly climb the city, which has a multi-functional compound combat capability.
The tower trough is combined with rams, ladders and other weapons to attack the city. It is powerful, and the offensive with rain of arrows can cause the defenders to suffer a lot.
…
Li Guangbi looked at the Yan army's siege equipment swarming towards the city, stroking the tiger's beard with his hand, sneered, and decisively ordered: "Prepare the trebuchet!"
Suddenly, he heard dozens of loud noises and looked for the sound. He saw flames rising into the sky and thick smoke billowing from the top of the city.
"Commander, it's not good!" A messenger stumbled over.
This messenger had been following him for many years, and if something big had not happened, he would not have lost his composure. Li Guangbi's heart tightened, and he suddenly had a bad premonition.
"Why are you panicking?" Li Guangbi asked in a deep voice.
"Commander, trebuchet... trebuchet..." The ordering soldier was frightened, hesitating and unable to express what he meant.
"What happened to the trebuchet?" Li Guangbi was worried.
"There has been a raid in the city, and more than half of the trebuchets have been destroyed!" The messenger gritted his teeth and told the bad news.
"Oops!" Even though Li Guangbi was always calm, he felt dizzy at this moment.
It turns out that during the Battle of Taiyuan, two brothers, Sun Dashan and Tu Xingsun, built a giant trebuchet for the Tang army based on the design drawings of Khwarizmi.
Compared with the trebuchets in the Central Plains, this kind of trebuchet was larger, had a longer range, more accurate projection, and infinite power, which caused Shi Siming to suffer a lot.
Shi Siming took advantage of the fierce fighting in Zhongli City to transfer Li Guangbi away from the North City and attract the Tang army's attention to Nancheng and Zhongli City.
Then, they secretly sent dead soldiers and craftsmen to destroy many trebuchets on the city at all costs.
This is the real reason why the Yan army dared to attack Beicheng.
Without trebuchets, how to defend against large siege equipment such as ladders and troughs?