As Sun Yu expected, the whole canyon was already in full swing. There was a deep pool in the canyon, and there were nearly a hundred tents sitting beside the pool. When Jianpu City was almost done, a number of brick houses would have to be built here.

, these craftsmen are their own wealth.

Sun Yu had previously purchased a batch of saltpeter and sulfur through Jianzhou Trading Company. He only needed to make some charcoal and mix it in proportion to get gunpowder. The top priority right now is to cast cannons. Compared with muskets, cannons are less difficult to make.

It is powerful. The key is that the world has never seen it before. It can shock people's hearts. If it is unexpected, it can have miraculous effects on the battlefield.

"I see you, Your Majesty." As soon as Sun Yu arrived, the three master craftsmen hurriedly came to pay their respects. Their family members had not yet come here, waiting for the Lord to repair the house here.

"I'm here today to have a big event. I'll leave it to you. Let's take a look at the drawings first." Sun Yu gave them the drawings he had drawn with charcoal in advance.

The three master craftsmen took a look and found that the object was about four feet long, eight inches wide, and had an inner diameter of about four inches. Such a large iron casting had never been made before.

"Sir, this thing is too heavy and heavy. I don't know what its use is." Master He has cast some large bronze items before, but he has never made such large iron items.

"This thing is called a cannon. Let's try to cast one first and see if it can work." Sun Yu just roughly drew it based on the appearance in later generations' memories. As for its power, there is no way to judge.

"Sure, let's try it." The three master craftsmen didn't have much to say. If you ask me to do it, let's do it.

"The size remains unchanged, and the caliber can be slightly changed based on this. Then make a five-inch caliber and a six-inch caliber." Sun Yu thought for a while, and the four-inch caliber will definitely not explode. After all,

The wall thickness is two inches. If the caliber can be made larger, it will not only be more powerful, but also the gun body will be lighter. What is the saying in later generations, caliber is justice.

The three master craftsmen nodded. It was not difficult. Just change the size of the mold. They nodded immediately and went to make the mold first. The most difficult thing for casting large ironware is the mold. As long as the mold is made, then

Just melt the iron and pour it in.

"Don't worry, get me some fish hooks." Sun Yu took a look at the deep water, which is a good place for fishing, and he was also hiding here. He was also a fourth-level governor after all.

Fishing is also an elegant hobby in your spare time.

An hour later, Sun Yu held a small bench and sat on the edge of the pool to hook a fish. Sun Sandao was responsible for threading the bait.

"Holy shit." A fish was hooked on a fishing rod. Sun Yu mentioned that he couldn't pull it at all. It must be a big fish.

"Sir, let me help you." Sun Sandao saw this posture and became more energetic, ready to help Sun Yu pull it together.

"Go away, just watch." Sun Yu said angrily. This guy probably doesn't know what a blasting pole is. The thing in his hand is either a carbon fiber from later generations, or an ordinary bamboo, just cut from the mountain. If he

If you pull hard, it's strange that the bamboo pole won't stop. Sun Yu pulls and releases it, playing guerrilla with the fish. When it gets tired, he can pull it up.

Finally, when the fish got tired, it slowly dragged it towards the shore and finally emerged from the water.

"Sir, this fish must weigh more than ten kilograms, right?" Sun Sandao wiped the saliva from the corner of his mouth. Such a big fish is definitely delicious.

"Go down and catch the fish, don't let it escape." Sun Yu concentrated on staring at the big fish below.

Without a copy net, such a big guy would definitely not be able to be pulled up.

"Don't worry, sir, I can't run away." Sun Sandao went straight into the water without rolling up his trousers. The big fish felt Sun Sandao's movements and started tossing again. Sun Sandao tried to hug him, but he couldn't hold back his hand.

None of them succeeded. If Sun Yu hadn't done it well, he might have disappeared long ago.

"Idiot, knock him out, hurry up!" Sun Yu urged as he noticed that the big fish was making more and more noise and could escape at any time.

Sun Sandao raised his fist and punched the big fish on the head. The fish's eyes flashed and it fainted. Sun Sandao put his hand through the fish's gills and finally got the big guy up.

.

"Cook it clean and add some dinner tonight. I'll see if I can catch some more." Naturally, Sun Yu would not clean up the fish himself, and it was not the time to follow his master all over the mountains and plains.

"Okay." Sun Sandao took out a short knife from his waist. With his skills, he was no worse than a chef in cooking this fish. He cleaned it up in a short time.

"You really have three knives." Sun Yu didn't notice it before. The name of these three knives is apt. He usually hangs two swords at his waist, but he didn't expect that there was one hidden inside.

"This sword didn't exist originally. The name "Three Swords" was just a compliment among the brothers. They thought my two swords were like three swords. I was always called "Three Swords" and my subordinates felt that I no longer carry one. I'm sorry for this.

"Name. Later I got a salary from the Lord and became richer, so I bought this short knife." Sun Sandao said with a cheerful smile, the three swords were just because he could use the knife as fast as possible.

Later, Sun Yu caught a few more fish one after another, but none of them were that big. Sun Yu found a big pot and stewed two pots of fish soup for everyone to try.

In the next few days, Sun Yu took three knives and kneaded the gunpowder with his own hands. In order to ensure the power, he kept changing the ratio based on the approximate memory of later generations, and finally got the optimal ratio. This thing must be kept extremely confidential.

, even the craftsmen cannot know that this is Sun Yu's biggest secret, which is enough to change the pattern of war. Sun Yu will never move this thing out until it changes the general trend of the world. As long as this thing is spread, sooner or later it will be

After all, there are many alchemists who know how to imitate gunpowder, but they have never thought of using it in war.

Ten days later, Sun Yu finally arrived with the artillery he had been dreaming of. Three black artillery pieces were lined up neatly, and three master craftsmen were polishing the barrels. There were also several apprentice craftsmen polishing iron balls next to them.

The outside of the iron ball is covered with a layer of lead, which is the artillery shell. The role of lead is to expand at high temperature during firing to improve air tightness, because the closer the barrel of the artillery is to the exit, the larger the size.

After the entire artillery was polished and mounted on the artillery cart that had been prepared long ago, it was pushed directly to the edge of the pond. When everything was settled, except for Sun Yu and Sun Sandao, only three master craftsmen were left to observe.

"This one should be loaded with some powder first." Sun Yu pointed to the artillery with the thickest barrel and said. He didn't know how much powder should be loaded in this one. Anyway, let's do it this way and try it slowly.

"Light the fire, retreat!" When Sun Sandao compacted the shells, Sun Yu and the three master craftsmen retreated dozens of steps, leaving Sun Sandao to light the fire. Sun Sandao took out the fire stick, lit it and walked leisurely towards

Go later.

"San Dao, hurry up!" Sun Yu and the three master craftsmen lay on the ground.

"Sir, I'm not talking about you, am I right?" Sun Sandao disagreed. How powerful could it be and how powerful it could be? It could catch up with a trebuchet. After all, this size can't be compared with a trebuchet.

.

"You bastard, get down!" Sun Yu was extremely angry. He was raised like a donkey, but he still didn't take it seriously despite all the warnings. He was at such a distance that it would be dangerous if his body exploded.

There was a loud "boom" sound, like thunder on the ground, the cannonball whizzed past, and then hit the water, raising a tall water column.

After firing "Three knives, three knives", Sun Yu came over and kicked Sun Sandao twice as he was lying on the ground.

"What?" Sun Sandao felt his ears were deafened and looked at Sun Yu in confusion.

Sun Yu was too lazy to worry about him, and he would be fine after a while. He walked to the cannon and took a closer look. The range of the cannon just now was about one mile, which was similar to that of a trebuchet. If he wanted to have an advantage in range, he had to add more medicine.

Sun Yu experimented with each artillery piece, constantly changing the amount of gunpowder used to find the best solution.

Throughout the afternoon, the sound of cannons continued in the Grand Canyon. If they had not known that the governor was testing new equipment here, the craftsmen would have been furious, thinking that the God of Thunder was angry.

After an afternoon of testing, Sun Yu finally figured out that the most suitable gun was the No. 2 gun, which was the five-inch caliber gun. With the same charge of one and a half parts, the four-inch caliber gun had a range of about 800 meters, and the five-inch caliber gun was about seven meters.

100 meters. But considering the power of the shells, the five-inch caliber is definitely more powerful and relatively lighter. As for the six-inch caliber, it charges one and a half parts and explodes directly. Fortunately, it is far away.

No one was hurt.

"Just like this cannon, how long will it take to cast fifty of them first?" Sun Yu asked the three master craftsmen, pointing to the five-inch caliber cannon.

"If we stop everything else and focus on casting, it will only take three months, provided there is sufficient iron supply." Master He counted on his fingers.

"There's no rush, other things can't be delayed. It doesn't matter if the artillery thing is a little slower." Sun Yu shook his head. No matter the various tools or armors and weapons, he can't stop. The artillery can't be used by himself for the time being, but he must prepare some.

Some gunners must also be arranged for training so that they can be used when needed.

"I'm afraid it will take a year. After all, just making molds takes a long time." After all, this craftsman camp has constant orders every day, and many skilled apprentices stay in Longmen Village. The output here cannot increase for the time being. Casting large parts, and finally

What matters most is the mold. It is too difficult to train a qualified mold master.

"What if we use iron molds?" Sun Yu seemed to remember that there was a book that mentioned that the method of casting cannons with iron molds is much faster than using clay molds. After all, clay molds are disposable.

"Iron mold? How to take it out?" Master He was stunned after hearing this. If the molten iron is poured in, it will stick together. How can it be used?

"What if we paint a layer of clay on the inside of the mold? If that doesn't work, just add some plant ash." Sun Yu didn't quite understand. It seemed like plant ash was used. Anyway, just separate the mold from the molten iron.

"You can give it a try." Master He's eyes lit up. Yes, you just need to use something to separate the mold from the molten iron. Wait until the molten iron cools, open the mold and clean it. Even if the gun body is rough, polish it.

Just click.

"Well, don't worry and try it boldly. The two masters will also follow you. If this succeeds, it will be a great achievement." Sun Yu looked at the other two master craftsmen and said, "Three cobblers, just like Zhuge Liang, if this can be done

After the iron mold casting method is completed, and there is enough iron material, it will be much easier to make large quantities of artillery.
Chapter completed!