As they were close, the people in the village saw that most of the returning people were dark and laughed in shock.

Coal is black, and anything sticks to it will definitely be covered with black and gray.

People and slaves carried sacks of coal all the way. The sacks were not sealed and would definitely fall from black and gray, and naturally they would become black people.

The people who were ridiculed were not annoyed.

They proudly raised their chests to those who laughed at them, and vividly told their hard work and the importance of black stones to sealing their thrones.

As a result, the ridiculed people stopped laughing and looked at the group of people who became black people enviously.

Lv Wu stood at the entrance of the village, watching the huge team enter the village, and loudly announced the rewards to the warriors and the people.

The reward is very generous.

The warriors and people who followed them out all smiled and opened their eyes.

In fact, whether it is a warrior or a people, it is natural for them to do things for the lord.

In other words, they are protected by the lord and work for the lord is a reward, and it is reasonable to have no salary.

Because the lord values ​​something, he believes that rewards should be made, which is another gain for the warriors and their people.

After announcing the reward, Lu Wu explained how to arrange the slaves he brought back, and he didn't have to worry too much about the rest.

For example, food, cloth and other items, Lao Zhuo will record and incorporate them into the warehouse.

Coal is sent to the workshop.

Cheng Ying was very curious about how Lu Wu would use the newly acquired slaves, so he asked him if he had any questions.

"The irrigation system in my territory is not good." Lu Wu actually didn't find any irrigation system, saying: "There are streams in the territory, and there is no shortage of water. You can dig ditches and distribute irrigation systems."

Not to mention, at this time, most countries in the Central Plains really do not have a perfect irrigation system, and they generally use water-loading tools to carry them on their shoulders and hands.

In the Chinese cultural circle, Qi State was the first vassal state to use national resources to build a systematic irrigation system. (It was established during the Guan Zhong period)

By the Warring States Period, Qin became the most complete power of irrigation system and far surpassed other countries.

However, for a long time, Qin's medical technology was far ahead of the rest of the country.

For a long time, Qin State relied on medical technology to improve diplomatic relations with various countries and maintain external friendly diplomatic relations. They had a team walking among the countries.

That medical team is called Bian Que from all countries.

(There was a miracle doctor named "Bian Que" during the Huangdi era. The medical organization in the Chinese cultural circle was also called Bian Que. Until a Qin Yue man with a very awesome medical skills were recognized, Bian Que was named by Qin Yue man)

Because there was no relevant concept, Cheng Ying was stunned when he heard this.

Lu Wu ignored Cheng Ying, who was confused, went back to wash, tied his ponytail casually, and rushed to the workshop with his wet hair.

The craftsman had seen the benefits of burning coal before. When he learned that Lu Wu had brought back a lot of coal this time, he was eagerly waiting.

The coal last time was only enough for Lu Wu to conduct a small experiment, and there was no big deal.

"Start the furnace!" Lu Wu ordered the fire to start, walked to a small hut, and carried a basket of charcoal himself when he came out. He needed too much to test, and ordered the craftsman and said, "Go and get some horse pee."

The craftsman didn't know what Lu Wu was going to do when he was urinating, so he went there with a confusion.

After thinking about it, Lu Wu asked those who didn't need it to leave, leaving only the craftsman they wanted to use, as well as the three warriors Qing, Lin and Zhi, who had been loyal to the old Lu family for many years.

Of course, he was to keep the necessary confidentiality, while the warriors were to keep their own safety.

Then, he asked him to get animal fat.

Of course, getting horse urine and animal fat is for quenching!

The furnace had been heated enough, and Lu Wu personally put the iron ingot in, waited for the iron ingot to melt, lifted the furnace with tools and poured the iron into the mold.

The next step is to forge.

Lu Wu's small body can certainly swing the hammer, but the strength is not enough and the endurance is not good.

He directed the craftsmen to perform repeated forging, and after cooling, he then put it into the furnace and melted it into molten iron.

It was melted and forged again and again, and repeated hundreds of times.

This is to remove the ore vein slag from the iron and make the iron purer.

This day passed through repeated forgings.

In the next few days, I was still performing repeated forging operations, and then I looked at the finished products separately, and conducted the remaining experiments.

For example, limestone is used to remove certain impurities from iron ore during the smelting process.

It was not until Lu Wu felt that the forged iron was enough that the second step was carried out.

On the twelfth day, Lu Wucai asked the craftsman to smash the charcoal and pound it into powder.

The iron was thrown into the furnace again, and a portion of weighed charcoal powder was added, and carefully stirred to make the two materials even.

When you take it out and forge it again, you no longer swing the hammer at will, but will make the iron into a long shape.

At this step, when heated again, it will not completely melt into molten iron again, and will only make the long shape burn red.

After taking it out, quenching is a double quenching method using horse urine and animal oil.

The craftsmen who participated stared at him by watching a series of steps.

They didn't know that there were so many steps to make a blacksmith and had to do so many tricks.

"Set it!" Lu Wu, with full expectations, put the long iron on the wooden table, immediately came over, stared at the things, and secretly commented: "It's like this to see the pattern. I don't know if the formula ratio is correct, and whether it has reached the desired hardness."

Whether it is hard depends on the experiment.

Lu Wu personally placed a long strip of iron on two stones with no force points in the middle, and said to the craftsman holding a hammer, "Smash."

Even if the craftsman has no culture, he knows that he needs to try his hardness, so he has set off a momentum and has struggled to continue.

A metal clash appeared.

The hammer hit the long iron, and the elastic force made the hammer swing open, and the long iron was bounced and dropped to the side.

Lu Wu, who was walking forward quickly, picked up a long strip of iron and took it in his hand to check it repeatedly.

The long iron curved to a certain extent, but it did not break.

Lu Wu once again placed the long strip of iron on the stone table and asked the craftsman to smash it repeatedly to see if it would crack or break.

After checking again, he couldn't control his excited heart and shouted: "I'm really awesome!"

The carbon content is 2.1~4.3% pig iron, which is hard and brittle, and can be cast but not forged.

The carbon content is 0.03~2.1% steel, which is characterized by hardness and toughness. It can be cast and forged.

The carbon content is less than 0.033% wax iron, and its characteristics are soft.

The carbon content of more than 4.3% is scrap iron.

The craftsman couldn't understand what Lu Wu was calling.

They could understand Lu Wu's expressions and actions, and became excited after they knew they had succeeded.

Although it took many days to divide it, the first time the production was successful made Lu Wu full of joy, but he did not finish the work immediately.

In the following period, he repeatedly changed the ratio of iron material to charcoal, or did not add charcoal, but instead added coal powder into the iron material.

At the same time, the double quenching method is no longer used, and horse urine or animal oils are used alone, and cold water quenching is also performed.

Different steps.

Different material proportions.

The results achieved each time are different.

One day, he was busy until late at night. Lu Wu, who was originally clean, once again turned into a dirty person, but he smiled extremely satisfied.

After learning that the work would be temporarily suspended, the craftsmen were no longer happy. They frequently looked at Lu Wu with dodging eyes, looking at him with worry and fear.
Chapter completed!