"In this way, it is not enough to just defend the city, now that the control of Hanshui has been obtained, the fortress line north of Fancheng has been broken, and now the fortress line south of Xiangyang should also be broken and land transportation should be restored." Sun Hui said, and the situation map of the battlefield quickly appeared in his mind.

"Lao Lu and Lao Jia discussed with everyone, and they also thought that it should be like this, so after resting for a day, they started to act early yesterday morning, Lao Lu led the army, Lao Jia led the water army, Sister Chu Chu and Linlin went to the water army to help, Lili went to Fancheng to help defend the city, and Sister Chu Chu asked me to protect you here." Xiao Tiantian looked at Sun Hui, her eyes were a little red, "I'm afraid you won't wake up, so I'll call you every once in a while to see if I can wake you up......."

"I haven't woken up for the past two days, you're worried about it, aren't you?" Sun Hui was moved in her heart, and shook her fingers with a smile.

"Hmm......" Seeing that Sun Hui was doing as usual, Xiao Tiantian became happy again, "Brother Sun, don't you want to see the cannon?" Sister Chu Chu has built a total of two doors, one in Fancheng and one in Xiangyang. ”

"Where? I'll take a look. Sun Hui was also very excited when she heard her say this.

"At the south gate, but it was not placed on the city tower, because the recoil was too great for the city tower to bear." Xiao Tiantian smiled and said, "Lili has built a sturdy fort there. However, because of the tight construction deadline and the fact that the steel is not too easy to get, Sister Chu Chu contributed her ironclad ship. ”

"Oh, it's hard for her." Sun Hui also regretted that the iron ship that was indestructible on the river had now become a cannon.

"Also, the cannonballs are also made according to the drawings you drew Brother Sun, not to mention, Brother Sun, your design is really great." Xiao Tiantian said, "How did you come up with it?" ”

"Hehe, it's just two key historical designs." Sun Hui smiled, "If you want me to think about it myself, I really can't think of it." ”

The two of them immediately got up and went to the fort, in order to test whether their ability had recovered, Sun Hui once again turned into a fire meteor, and inspired by Sun Hui, Xiao Tiantian also got a big water balloon for himself, which could fly in the sky like Sun Hui.

The two soon flew to the top of the fort, and the gunners on the platform saw the two falling from the sky, and immediately they all bowed to the ground.

Sun Hui asked them to get up and asked the gun commander about the process of manipulating the gun, the gun commander first took out a piece of paper full of gun procedures and gave it to him, and then asked him to question the gunner, the gunners answered like a stream, Sun Hui observed their actual operation again, and found that although it was only a little more than two days, these people were already able to master the gun operation process, and they couldn't help but be very pleased.

Then Sun Hui looked at Ye Chuchu's DIY shells according to his drawings, and found that these huge spherical grenades were made exactly as he required, and couldn't help but secretly admire Ye Chuchu's cleverness.

The historical "Urban Cannon" fired a solid huge spherical stone projectile, but this time he designed Ye Chuchu to make it with his hands, but it was a real flowering cannonball, that is, a hollow explosive projectile, the predecessor of the modern grenade.

A grenade is an explosive bomb, which is caused by fragments of the shell after the explosion of gunpowder. In the early days, due to the material, the inner wall of the cartridge case could not be too thin to withstand the chamber pressure generated by the gunpowder in the enclosed space of the barrel, or it would explode in the barrel. However, if the inner wall is thick and the charge is too small, it will form a stew explosion, and it will not be able to explode the shell to cause damage. The grenade created after such a compromise has a small charge, and the power of black powder is enough to choke, resulting in very few fragments after explosion, and the lethality is very limited.

In actual combat, the spherical grenade is ignited by the powder twist, and the grenade is divided into two steps: igniting the powder twist and igniting the fire rope at the end of the gun, the operation is complex and dangerous, the powder twist fuse must be placed in the direction of the muzzle, otherwise the fuse is ignited in advance, it is the end of the cannon destruction and death, and in the fierce battle, the shell is placed in the wrong direction is a common thing. So until the 18th century, cannons and solid shells were the mainstream of the battlefield, and howitzers played a supporting role for a long time, until the advent of wooden conical tubes and wooden cartridges.

The wooden conical tube and the wooden cartridge technology were two inventions that were easily overlooked by the people of the time, but they had a great effect, and they had a huge impact on the history of artillery.

The technology of the wooden conical letter tube is very simple, that is, the hollow conical wooden stopper, the wooden plug hole is loaded with gunpowder, the letter tube is plugged from the ignition hole of the hollow shell, slightly higher than the surface of the sphere, when fired, because there is a certain clearance between the smoothbore gun and the shell, the high temperature of gunpowder burning will pass through the gap between the shell and the gun wall, igniting the front of the letter tube, which not only saves the trouble of igniting the shell fuse and firing the gunpowder bag at the same time, but also avoids the danger caused by misoperation.

The wooden conical letter tube was invented as early as the late 18th century, but it was buried because the field howitzer of the time was too low to be taken seriously.

Early wooden cartridges were also used on solid bullets, and later gradually applied to flowering bullets; The wooden cartridge butt seems simple, but Sun Hui has always believed that its role is not inferior to the invention of the wooden conical letter tube, especially when firing hollow grenades on guns with a longer diameter of the gun. Due to its low strength, the early cast iron-hulled blasting shells could not withstand the high chamber pressure of long-barreled cannons, so they could only be used on low-chamber pressure howitzers. In addition to effectively sealing the gas leakage, the soft wooden support on the tail of the shell can also play a buffering role on the hollow grenade when fired, and the grenade launched will cause the "badminton principle" self-stabilizing structure of the head and tail due to the light wooden support, which makes the trajectory more accurate, there is a grenade and shrapnel during the American Civil War is this structure, of course, the kind of shrapnel has belonged to the modern industrial production of weapons, the wall is thinner, the manufacturing requirements are higher, and the structure is more complex.

In fact, the fixed shell is a further refinement on the basis of the wooden conical tube and the wooden butt. Traditional artillery firing needs to determine the amount of gunpowder with a measuring tool or experience, and it is easy to blow up the chamber if there are fewer shells. The artillery of the 17th century required an experienced gunner to operate, and it was not something that could be played by just anyone. The fixed artillery shells that appeared in the 19th century are based on the wooden cartridge butt, the gunpowder required for firing is packed into a package, and the shell, the cartridge stock, and the cartridge are fixed into a whole, and the fixed shell is ignited as long as it is stuffed into the fixed shell when fired, without the need for a complex charging process, and a soldier can operate it after simple training. As a result, the rate of fire of the artillery increased significantly.

Because Ye Chuchu's ability to control metal has greatly changed the material of this super cannon, it almost has a generational advantage over the famous "Urban Cannon" in history.