Yu Ren passed. Sure enough, the person who had been hiding in the shadows and quietly peeking at their words and deeds was none other than Xu Shichang, the son of the Xu family. However, he didn't have a retinue with him at this time.

Xu Fatzi was startled when he saw Yu Ren walking towards him.

Only then did he remember that he had discovered such an important secret of others, but he was still stupidly and openly screaming for the other party to find out. It seems that this little life of his own may not be guaranteed. But he also knew that with his own speed of action, if he wanted to race against Yu Ren and them, it was absolutely hopeless.

So in the end, Xu Fatzi made the wisest choice - sit back and wait.

Yu Ren walked up to Xu Fatzi, he didn't draw his knife or pull out his dagger. Xu Fatzi kept staring at Yu Ren's hands with a nervous expression. Although he did not intend to run, he did not give up his resistance. He was anxiously awaiting Yu Ren's verdict against him.

When Xu Fatzi didn't know how Yu Ren was going to deal with him, he saw Yu Ren suddenly stretch out his hand to him.

"Do you want to do it with us?"

Xu Fatzi was stunned for a long time, as if he didn't understand Yu Ren's words, and then nodded heavily.

"Okay, then let's study the next hot air balloon together!"

In this way, Yu Ren easily tricked Xu Fatzi out of the woods where he was hiding, and pulled him onto their thief ship.

Although Huang Wu and Cao An were both opposed to Xu Fatzi's participation, Yu Ren was determined to let Xu Fatzi participate. Huang Han did not speak. In the end, the two had to give in.

That night, several people studied all night in this small stone house in the mountains, and no one went back. When it was almost dawn, Yu Ren felt that he should have thought it through. He then re-marked his design on a piece of paper, then marked the dimensions on it, and finally wrote down the materials used in each part of the paper together.

After doing all this, Yu Rencai lay down on a straw mat in the house.

The next day, Yu Ren got up after three strokes. When he woke up, he found that only he and Cao An were left in the room. He still thought that what happened to him yesterday was just a dream at night.

"What about them?"

"They all went down the mountain to collect materials. Xu Fatzi was afraid that the fifty taels of silver in Huang Han's hand would not be enough, so he went home to get the money again. ”

Yu Ren was taken aback. "Fifty taels isn't enough?"

"My lord, what's so strange about this. You don't want to think about it either. What kind of materials did you choose? The shelves were to be made of light and strong iron, and the balloon cloth was to be sewn from animal skin, and then sealed at the seams. Just to make such a big hot air balloon, how much skin does it take?

This is also the most expensive one of our productions. Even with the worst skin, I estimate that it should cost at least sixty or seventy taels of silver. ”

"That's a lot!"

Yu Ren began to regret his decision to choose animal skins for hot air balloons, but for the time being, he couldn't think of a better alternative. In this dynasty, he really didn't have a better material to replace animal skins, which could be breathless and not too heavy. Therefore, he could only secretly warn himself in his heart that this time, he must be careful not to let the hot air balloon fall into the mountain stream again.

He spent a lot of money to make it, and even if it didn't work out this time, he had to reuse the material in every way possible. Otherwise, it won't take a few times, and they will go bankrupt.

On this day, Yu Ren felt that time had passed a little long. The three who went down the mountain, except for Huang Wu, who went up the mountain at noon, brought back some food and sundries; Huang Han and Xu Fatzi have not yet returned. Yu Ren began to feel more and more the inconvenience of not having a phone call in this era. So he had no choice but to take out the drawings he had designed again and again and scrutinize them again and again. He hopes that this time, they can succeed at once. Otherwise, after failing again and again like this, he feared that he would soon become a poor bastard again.

In the afternoon, Xu Fatzi rushed back to the mountain. He said that he went to help Huang Han buy materials, so he came back late. Yu Ren didn't blame him, so they sat down together again and studied the possible problems with this drawing.

It was almost evening when Huang Han returned to the mountain. He also brought two other teenagers with him. Both of them were also the opposite of his age.

"This is Li Fu. Their family is a family of carpenters, and the strange wooden tools in my house, which are now useless, are from him. Huang Han pointed to a tall, lean young man.

Yu Ren nodded at Li Fu, he knew him.

"This is Liu Datou. Their ancestors were iron-struck. The big head's craftsmanship is no worse than his father's. Several of us are iron buddies who have grown up together. When I was a fire dragon, they all came to see me many times and helped me a lot. I told them that we were going to make a big ball that could fly into the sky. They listened and wanted to participate. As he spoke, Huang Han looked at Yu Ren. Obviously, although he is the master of this place, he thinks that Yu Ren is their real head now.

"Welcome, welcome!" Yu Ren was happy about the arrival of Li Fu and Liu Datou from the bottom of his heart.

With the addition of Li Fu and Liu Datou, Yu Ren's research team has grown a lot, especially because one of these two people is engaged in carpentry and the other is iron, they have enough understanding of the current level of craftsmanship. This also helped Yu Ren to know which designs could be done when designing hot air balloons, and which ideas were not yet available in the current process, and needed to find alternative methods.

For several days, Yu Ren spent time in the mountains, and in order to get a hot air balloon out, he could almost be said to have forgotten to sleep and eat. Yu Ren now realized that it was very expensive to make this thing, and in order to save money, he asked Cao An to return the high-end inn they lived in the west of the city the day after he went up the mountain, and the luggage was also moved to Huang Han's shop.

A few people nested on the mountain, vowing to realize this dream of flying.

Their meals were delivered every day by a member of Xu Fatzi's family. This family is Xu Fatzi's follower since he was a child, and he is also a person who absolutely believes in it. Therefore, you don't have to worry that their affairs will be discovered by the adults of each family, and then come and drive them back.

Of course, because except for Yu Ren and Cao An, the rest of them have homes in the city, and every day they go up the mountain early in the morning and go down before closing the city gate. At night, Yu Ren and Cao An were left in the stone house.

Early in the morning, Yu Ren was revising the design drawings for a location that was not properly designed, and Xu Fatzi rushed up the mountain in a hurry.

"Why are you so happy. Are you picking up gold, or are you picking up your daughter-in-law? Yu Ren didn't look up, still revising his design drawings. Can you help me see if it will be safer after this change? ”

Yu Ren invited Xu Fatzi to join at first, to be honest, it was all because he fell in love with him, the God of Wealth. Hopefully, he can help them solve some financial problems with their research. However, he soon realized that he was completely wrong. Although this Xu Fat Man is not very good-looking, he is absolutely ingenious, and he also has a strong interest in tinkering with these novel things.

What makes Yu Ren most relieved is that this Xu Fat Man must have read a book. Although the four books and five classics are poor, Xiucai did not pass the exam, but the foundation is still there. In the past few days, Yu Ren asked him to go home and read more practical books on science such as "Nine Chapters of Arithmetic". During the day, when he was in the mountains, he told him some common principles of modern physics.

Every time he talks about some principles of modern physics, Yu Ren always brings everyone together.

Soon, Yu Ren discovered that Xu Fatzi's understanding in all aspects had gradually surpassed Huang Han, and it was even more obvious to Huang Wu and Li Fu and Liu Datou.

When he first joined, Xu Fatzi was still very low-key. Everyone only looks at him as an errand runner. Soon, however, several people began to discover his talent. So much so that in just a few days now, he has faintly become the first deputy of Yu Ren for this project, and he has begun to command Huang Han and several of them.

But today, Xu Fatzi didn't come to talk to Yu Ren about hot air balloons. He walked up to Yu Ren and whispered to him, "There is a lively scene by the West Lake this afternoon, do you want to go and see it?" ”