My younger brother Zhuge Liang

Chapter 494 You have a ladder, I have a plan

Jia Xu tried his best to stop Xiahou Yuan and prevent him from acting impulsively. But after all, Xiahou Yuan's nephew had just died, so how could he suppress his anger so easily?

So the day after Xiahou Shang was killed, Xiahou Yuan organized another frontal attack.

However, Wei Yan was not idle either. After a night of reinforcement, Wei Yan raised the southern section of the east wall of Diaoyucheng, which was originally exposed deliberately, by more than one foot, making up for the weakest short board a little bit.

In addition, countless rockets and rolling stones were transported to the top of Diaoyu Mountain, which is close to the southern section of the east wall, to replenish various supplies for the city defense war.

After all, Cao's army had just been annihilated yesterday, with several thousand men killed, and many soldiers were burned by the flames and fled back miserably. As a result, the morale of Cao's army was generally much lower than the day before.

Therefore, Xiahou Yuan's frontal attack ultimately failed to make any progress.

Wei Yan, the defender, showed a far more resolute will than the day before, personally supervising the battle, and the crossbow firepower of the defenders on the wall was even more intense than on the first day. Wei Yan also personally led the reserve team to patrol the top of the wall to plug leaks, and blocked the Cao army that occasionally climbed up the wall with ladders.

This also proves that if Wei Yan wanted to hold out against Cao's attack, it would not be impossible given the strength of the current fortifications and the completeness of the enemy's siege equipment.

For Cao's army, the only thing to be thankful for in the second day's siege was that the troops were not surrounded and annihilated as a whole - if you couldn't break through the wall and your troops didn't penetrate deep into the encirclement, how could you be surrounded and annihilated?
In a direct contact war, a thousand casualties a day would be enough. Compared to a one-time annihilation war involving thousands of people, this loss was still within an acceptable range.

Xiahou Yuan personally supervised the siege, but still failed. He was finally calmed down by the cold water poured on his head, and realized that it would be impossible to succeed without catapults, Ge Gongche and ladder trucks.

In the last two days of September, Xiahou Yuan finally came to his senses and changed his tactics, stopping the quick attack and giving his troops ten days to half a month to prepare and slowly build heavy siege weapons.

……

Xiahou Yuan stopped the attack, but Wei Yan certainly would not sit idle either.

After confirming that Xiahou Yuan had shifted his focus to building siege weapons, Wei Yan immediately seized the time to continue strengthening the city's defenses and building new defensive facilities.

Sharpening the knife does not delay the chopping of wood. Before starting, he did not forget to hold a military meeting to discuss the construction plan with Zhuo Ying and other deputy generals and military officers so that he could have a clear goal.

Wei Yan got straight to the point and asked, "What do you think Xiahou Yuan will focus his manpower and resources on when he is temporarily dormant?"

Everyone present immediately started discussing and brainstorming, and they quickly sorted out several possibilities.

Finally, Zhuo Ying summarized and analyzed, "Xiahou Yuan will probably focus on building ladders, chariots, and catapults. As for battering rams, there is only one tower and gate on the east wall, so they probably won't be used much. And the siege towers will probably not be used."

After all, Wei Yan was young and it was impossible for him to think comprehensively about tactics. He did not react for a moment to why the well guard could not be used, so he asked another question.

Zhuo Ying pointed to the main peak of Diaoyu Mountain nearby and said, "The well guardrail is only useful for plain cities. It must be high enough to overlook the city walls. But Diaoyu City has a main peak to the south. No matter how high the well guardrail and watchtower are, they will be suppressed. Xiahou Yuan's efforts should not be in vain."

Wei Yan was slightly stunned, but soon realized that he was blind to the truth. Fortunately, he had sorted out these blind spots during the military meeting before the war, so that the subsequent efforts would not be wasted.

It was normal for a young general who was less than 25 years old to be unable to think of it for a while, and he had to continue to grow in actual combat. Although Zhuo Ying was not a famous general, he was more than ten years older than Wei Yan, so he could naturally provide some experience to supplement Wei Yan.

After Wei Yan sorted out the enemy's preparation ideas, he began to discuss how to carry out targeted defense.

The first thing he thought of was to use this time to continue raising the height of the east wall.

However, after this idea was put forward, everyone discussed it and felt that it was very difficult and the results would not be very good.

"Captain Wei, no matter how high this earth wall is, as long as Cao's army has the Ge Gongche, they can still reach the top. It will take Cao's army at most half a month to build siege equipment.

With tens of thousands of us, how high can we make the three hundred zhang wall in half a month? It is more than ten zhang now, and it will be more than two zhang by then, but Ge Gongche can easily make it thirty or four zhang high. "

Wei Yan listened to the advice and thought it made sense.

To raise the city wall, you cannot simply increase the height, because the cross-section of the wall is a trapezoid. If you want to ensure its stability, you must create a gravity dam. If you double the height, the cross-sectional area becomes four times larger.

It can be said that the construction volume of a two-and-a-half-meter-high wall can be four times that of a two-foot-high wall.

Moreover, if the defenders want to raise the wall, they need to raise the entire wall, but the attackers only need to break through a small part. This method of strengthening defense is obviously not suitable for quickly improving combat effectiveness in a short period of time. However, after the war, if there is an opportunity to slowly strengthen the city defense in peacetime, they can try to raise the wall generally and then cover it with bricks and stones.

Since the idea of raising the city walls completely has been ruled out, there are not many options left.

Wei Yan and Zhuo Ying discussed for a while, and finally they put their heads together and brainstormed, and Wei Yan had a flash of inspiration and came up with a trick:
"Got it! Although the Ge Gongche is powerful, its center of gravity is relatively unstable. This weakness is also what Mr. Zhuge has repeatedly warned us about, so the Ge Gongche cannot be used on steep terrain! It may fall over by itself with a little push! On the hillside, we can only use equipment such as ladders and wooden donkeys to propel it.

Therefore, we might as well leave the east wall as it is and not raise it any higher, so as to paralyze Cao's army. But in fact, our army secretly raised and widened the second antler trench defense line behind the east wall to create a second "east wall".

The advantage of this is that the East Wall was originally located at the edge of the steep slope of Diaoyu Mountain, and most of the land outside the East Wall was soft and flat. After passing the East Wall, continuing to the west, the terrain between the East Wall and the original second antler has gradually become higher and the slope is relatively steep.

Once Cao's army uses the Ge Gongche, they can only use it to attack the first east wall. The second wall is on a steep slope, and the Ge Gongche cannot be pushed up at all. Other heavy equipment will also be useless if the center of gravity is unstable. "

After listening to this, Zhuo Ying and others thought about it for a while and admired Wei Yan for being a quick learner. He actually came up with a new defensive tactic for him.

The Ge Gongche can only be pushed over from the plains to attack Pingcheng! It is impossible to push it under the wall in the mountainous area with a larger slope!

Of course, some readers may find it strange: Since Wei Yan could think of this, why didn't he just move the wall back a hundred steps or so and build it to a relatively steeper position on the hillside when he dug the "East Wall" to resist Xiahou Shang for the first time?
If we retreated to the steep slope the first time, wouldn't we have saved ourselves the trouble a second time?
But if you look closely, you will find that Wei Yan's approach was clever.

When he built the first wall, he really couldn't just retreat to the steep slope to build it.

Because the land on the plain is relatively soft, it is suitable for quickly digging a large amount of earth. At that time, Wei Yan had to race against time and dug deep trenches on both sides of the east wall. The outer trenches were used as pits to delay the enemy, and the inner trenches were used to bury firewood and fish paste, and to facilitate the fire and stone arson on the top of Diaoyu Mountain.

If you build a wall directly on a steep slope, the loose soil on the ground is very thin, and you will immediately find the rocks on the mountain when you dig deeper, and you can't dig it out at all. In that case, you can neither make a deep enough pit nor get enough soil on the spot.

But now it is different. Wei Yan can equip the first wall with a deep pit that can delay siege weapons, so the second wall does not need a deep pit. He can specialize in one thing.

Moreover, we have much more time now, so digging soil and transporting it from somewhere else is no longer a big deal.

After comprehensively considering all the above factors, Wei Yan decided on a defense plan of "two rammed earth walls inside and outside" and upgraded the second line of defense while Xiahou Yuan was building siege weapons for half a month.

After having a plan, Wei Yan naturally acted decisively and began to expand the deer horn trench behind the east wall that day and transform it into a new inner city wall.

During the construction process, some new optimization and adjustments naturally emerged with the practice.

For example, on the fifth day of construction, as the second earth wall began to take shape, Wei Yan suddenly realized that the first wall and the second wall could be connected with a longitudinal earth wall corridor, so that the front and back walls could form a "U" shape, achieving an effect similar to that of a urn city.

Of course, a normal 瓮城 should be in the shape of a "口", with longitudinal connecting walls on both sides.

But Wei Yan considered the actual terrain of Diaoyu Mountain and thought that there was no need to do so. Because the north side was a cliff close to the Jialing River, there was no need to build another wall there. Only the corridor on the south side near Diaoyu Peak would be left. With one less road, it would be easier to defend.

With the connecting corridor on the top of the wall, the stairs leading to the top of the wall on the back of the first east wall can be completely removed. In this way, even if Cao's army broke through the city gate and rushed into the inside of the first wall, they would not be able to run to the top of the wall through the stairs.

Just like other 瓮城, there is no staircase to the outer wall. One can only climb to the top of the wall from the inside and then go to the outer wall through the connecting corridor.

Of course, wall stairs have their pros and cons, and connecting corridors have their pros and cons.

The disadvantage of the connecting corridor is that if the enemy does not break through the outer wall by breaking through the door, but instead climbs directly to the top of the outer wall by climbing up the ladder or using a siege weapon, they can also run directly to the inner wall along the corridor.

However, considering the specific terrain of Diaoyu Mountain, the only connecting corridor built by Wei Yan happened to be within the range of the rolling stone attack suppression of Diaoyu Peak.

Therefore, even if Cao's army captured the outer wall with the help of Ge Gongche, they would be hit by boulders along the way if they wanted to run to the inner wall along the corridor, and the road might even be blocked by boulders.

Wei Yan had thoroughly mastered the treacherous terrain of Diaoyu Mountain.

Xiahou Yuan spent half a month frantically upgrading siege equipment, thinking that he could rely on heavy equipment to steadily break into the city. However, he didn't know that Wei Yan's defensive fortifications were improved faster than his.

When Xiahou Yuan was finally able to end his seclusion and launch a general offensive, what he had to face was a Diaoyu City that was completely different from the one he had faced half a month ago.

(End of this chapter)