However, there is also good news, that is, the Daming Arsenal in Nanjing is already trial-producing Hongyi cannons, and they are produced according to the technology of the Macau Bugalao Cannon Factory, which means that standardization is about to be achieved.

Looking at Jiannu on the opposite side, he has already begun to push out the Hongyi cannon.

The scene was really huge. A large number of Hongyi cannons were lined up at a distance of about a thousand steps. The distance between two adjacent Hongyi cannons was about ten feet. The total length of the artillery position was more than two miles.

[Note: One mile in the Ming Dynasty = 150 feet = 480 meters]

Judging from this length, there are at least 300 Hongyi cannons.

Jin Shenghuan said in a deep voice: "Your Majesty, it seems that Jiannu is going to attack with the Hongyi cannon this time."

"It's expected." Chongzhen smiled and added, "However, Jiannu will soon realize that this is in vain. If he wants to break through Xuzhou's defense line, he still has to pay for it with human lives."

The bastion was specifically designed for anti-cannon use.

Because since the emergence of cannons, the traditional high-walled and thin-walled castles in Europe have become vulnerable. In order to strengthen the defense of the castle, the strategy of building bastions outside the castle came into being.

The bastion can easily withstand cannon fire due to its low, inward-sloping and extremely thick walls.

Moreover, there is usually a slope protection outside the trench of the bastion, and the height of the slope protection is usually the same as or even higher than the fort wall, which makes it difficult for cannons to hit the bastion wall.

Because the slope protection outside the bastion must be cleared first, and the cannon's firing interface must be cleared.

However, in the process, the bastion must be covered by firepower, so the attacker usually needs to spend a lot of time and pay a lot of casualties to destroy a bastion.

With the human resources of the small European countries at that time, the bastion tactic was basically unsolvable.

Combined with the current Xu Zhan War, the human resources of Jiannu are not much stronger than those of European countries. Therefore, not to mention the bulldozing of more than 600 gun towers with twelve levels outside Xuzhou City, there are only two gun towers on the outermost perimeter.

It's enough for them to drink a pot.

Even the most conservative estimate is that each gun platform can take away at least one thousand to two thousand slaves.

So Chongzhen wanted to see how far the slaves could endure? How many casualties could they endure?

After the Eight Banners Han Army set up the Hongyi cannon, they began to fire the cannons one after another under the command of the Han army generals.

The scene was really astonishing. More than 300 cannons fired one after another, and the muzzles of the cannons sprayed out balls of flames, followed by a huge roar.

The ground shaking can probably be felt from the nearest musket stations.

Chongzhen adjusted the sight of the telescope and saw that most of the shells fired by the Jiannu Hongyi cannon landed on the slope protection of the first turret on the outermost side, leaving patches of black soil.

A small number of shells also fell into the gun platform at the rear.

However, there were no casualties, and the Ming army was hiding in the bunker at this time.

Therefore, despite the excitement of the Jiannu and Hongyi artillery fire, the killing effect was actually zero.

Such a bombardment, even if Jiannu used up all the gunpowder and lead bullets, would not be able to destroy the outermost slope protection.

"A worm can shake a tree." Chongzhen finally felt relieved, put down his telescope and said with a smile, "Let the Jiannu waste their gunpowder and lead bullets. We'd better hurry up and make preparations."

"Yes." All the officers and men agreed.
Chapter completed!