The Military Governor in Dream of the Red Chamber

As an experienced master craftsman, Lu Dahai knew very well that the coal in Datong was not suitable for direct iron smelting because the iron was of inferior quality and too brittle to be used in firearms, which would easily cause the barrel to explode.

The imperial court stipulated that iron used in the manufacture of firearms should be preferably from the south, such as Fujian iron.

That's because there are forests to the south with timber that can be used to make charcoal.

Charcoal is the best material for iron smelting.

The trees in Datong have long been cut down, and the price of charcoal is high, which has led to a surge in the cost of using charcoal to smelt iron.

Jia Chen knew the principle behind it. Coal contains many impurities, especially sulfur, which makes iron brittle and basically unusable for firearms manufacturing.

However, in order to save costs, the north could not use charcoal and could only use coal. The so-called wrought iron produced in this way was just scrap iron.

How can firearms made from such inferior scrap iron be of good quality?

Jia Chen's method involves coking and desulfurizing the coal, and then adding quicklime or limestone during ironmaking to allow it to react chemically with sulfur for further desulfurization.

In fact, Jia Chen knew that although the craftsmen of the Great Hong Dynasty did not know the underlying principles, they did know that better iron could be produced by using coking coal.

However, coking also incurs costs, and in the end, iron is often produced directly from coal.

Datong is rich in coal mines, so it's easy to get coal, and the price isn't high.

That's why Jia Chen wasn't too concerned about the pig iron He Liding gave him, because the cost was controllable.

"We'll know if it works after we try it out," Jia Chen said confidently.

Under Jia Chen's leadership, a simple kiln was built in Qianshanbao City.

Given the current conditions, we can only use traditional methods to produce coke.

However, Jia Chen believed that as long as he maintained strict standards and did not cut corners like the Da Hong Army, the quality would definitely be guaranteed.

Before coking the coal, Jia Chen also screened the coal.

Because coal with high sulfur content is heavier, after crushing the coal, it is poured into a water tank. The coal that floats is the coal with low sulfur content, while the coal that sinks to the bottom has high sulfur content and is discarded.

After the first screening step, these low-sulfur coals are used for coking.

After being refined into coking coal, it needs to be further desulfurized, which involves adding quicklime or similar materials to solidify the sulfur into coal slag.

After multiple desulfurization processes, although coal is used to smelt iron, the final iron produced can approach the quality of iron smelted with charcoal.

The greatest loss in the process of turning pig iron into wrought iron lies in the repeated heating and forging to remove impurities.

Because of the various desulfurization and impurity removal processes performed by Jia Chen, the subsequent heating and forging can be effectively reduced, thus greatly reducing losses.

In addition, Jia Chen optimized the blast air and increased the furnace temperature.

The original large wooden bellows was improved into a piston-type bellows, and the air duct was optimized to provide a more stable and stronger airflow, thereby increasing the furnace temperature, allowing for more thorough separation of impurities, and improving ironmaking efficiency.

Using Jia Chen's method, they indeed produced high-quality wrought iron, which could be called refined iron.

Lu Dahai was amazed.

Not to mention that the coal is usable, the loss of pig iron is also very low.

It's incredible that ten pounds of pig iron can be refined into six pounds of refined iron that can be used to make cannons.

Even with his extensive experience, ten pounds of pig iron could only yield about two pounds of wrought iron suitable for cannon making using charcoal.

Jia Chen's method more than tripled the output of wrought iron.

Moreover, because the number of forging operations is greatly reduced, labor costs are also reduced, and efficiency is higher.

Jia Chen entrusted Lu Dahai with the forging of refined iron and the manufacturing of the Tiger Crouching Cannon.

The rest of the team devoted themselves entirely to the construction of the walls and moats.

These are the most important things. As for other amenities within the city, Jia Chen doesn't care too much about them now. He just wants to build some earthen houses to provide shelter from the wind and rain.

Besides construction, Jia Chen also took time to have his subordinates participate in drills, especially some coordinated formations.

The current firearms density is insufficient. If the Northern barbarians do manage to scale the city walls, they will need to have people with spears and lances to assist them.

Jia Chen also attaches great importance to discipline, such as lining up.

An army without discipline and unable to obey orders is ineffective in combat.

After finishing the construction work each day, Jia Chen would set aside time to do these things.

At first, Wang Baisheng and the others didn't understand, but under Jia Chen's strong orders, they gradually got used to it.

Jia Chen did not give up on the idea of ​​improving the musket, but Lu Dahai told him that he was not proficient in muskets.

He's fine if it's just some minor repairs.

He was powerless to do anything about major repairs, let alone rebuilding.

According to Lu Dahai, most of the craftsmen skilled in making muskets were in the capital, while the border towns could only produce some simple firearms, and the more advanced ones were transferred by the imperial court from other places.

The artisans in the capital are not easy to recruit; I can't very well go there and poach them, can I?

Speaking of which, my future father-in-law works in the Ministry of Works, so he can barely be connected to these matters.

However, Qin Ye doesn't have much real power, so he probably doesn't have much of a chance.

As for the Jia family, Jia Chen only thought about it for a moment before giving up.

The Jia family probably won't get involved in these matters.

Besides, I'm just a minor official; it's not worth putting the Jia family at such a risk.

In addition, Jia Chen thought of some firearms craftsmen in the southeastern coastal areas.

For example, Zhejiang was on the front line of the fight against Japanese pirates and had advanced firearms.

Fujian's Min Tie (Min Iron) is famous for its expertise in manufacturing large cannons, such as imitations of the Hongyi Cannon.

Also, in Guangdong, due to Macau, people had access to some Western firearms.

Unfortunately, his social status was still too low, making it unrealistic to recruit craftsmen from those places.

Putting aside whether we have the means to attract these people, we should at least offer them sufficient wages, right?

Jia Chen doesn't have much money right now.

The most important point is that the distance is too far, and it is impossible for Jia Chen to go to the southeast coast.

This path seems to be only a pipe dream.

The weather was getting colder and colder, and Jia Chen brought his hidden gold and jade jewelry to Desheng Fort to find Lin Heqing again.

He wanted to buy a batch of cotton-padded coats this time.

Originally, winter cotton-padded clothes were issued by the imperial court, but unfortunately the imperial treasury was empty, and with layers of deductions, the lower-ranking border troops had not had new clothes for many years.

The tattered cotton-padded jackets worn by Wang Baisheng and the others looked to be from several years ago; they were worn out and patched up.

Those who have tattered cotton-padded coats are considered lucky; some don't have any at all.

Liu Tianwang provided some, but unfortunately, the quantity was far from enough. There was still a shortage of 300 people, so Jia Chen had to find a solution himself.

Lin Heqing mainly deals in grain here, but he also deals in other aspects of daily life such as clothing, food, housing, and transportation.

An ordinary cotton-padded jacket costs a little over 0.3 taels, so 300 sets would cost around 100 taels. Lin Heqing would give Jia Chen half price, which would be 50 taels.

Jia Chen also took out his gold and jade jewelry, wanting Lin Heqing to help him exchange it for silver.

Here, Jia Chen could only trust Lin Heqing.

At least Lin Heqing showed me enough kindness.

Lin Heqing was surprised. Jia Chen had only said that these were spoils of war obtained from the Chahar tribe.

Lin Heqing was willing to believe this claim, after all, Jia Chen had previously beheaded many Northern barbarians.

In the end, Lin Heqing accepted the jewelry for 1100 taels of silver.

"Manager Lin, are you going back now? Have you finished dealing with the properties here?" Jia Chen was somewhat surprised to hear that Lin Heqing was preparing to leave Desheng Fort and return to Jiangnan in a couple of days.

"No, it's still dragging on," Lin Heqing shook his head and said. "The Sun family is busy with other things lately, and their minds aren't on me. Since that's the case, I won't waste time with them. I'll come back next year when the weather is warmer."

"What are they busy with?" Jia Chen asked, somewhat curious.

Sun Shaozu wanted him dead, so Jia Chen naturally didn't want to let go of any news about Sun Shaozu.

"What else could it be?" Lin Heqing shook his head and said, "It's just transporting things north. This time it's on a large scale; the Sun family is secretly stockpiling goods."

Jia Chen understood; it was still smuggling.