Anyway, I can't leave the house for the time being, and I have time. Although his father asked him to prepare for the township exam, he knew very well that no matter how hard he tried, he would not be able to pass the exam.

Because of the township test, Li Ying's matter cannot be mentioned to his father for the time being. Yu Ren was a little depressed. He decided to send someone to Hangzhou to send a letter to Li Ying. The best candidate for this letter delivery is naturally Cao An. But Cao An can't be sent out now. Otherwise, he will really be locked up by his father every day and can't get out.

It seems that it is better to ask Huzi and them to help, and find someone to deliver a letter on his behalf.

After thinking about Li Ying's matter, Yu Ren then thought about the problem in front of him.

It is no problem to add a propeller to a small boat. This kind of small boat, as long as you add a rocker-type one, you can do it. Very simple. But when it comes to the big ship, the propeller will have to increase in size. In this case, this motivation becomes a big problem. Regarding the question of whether it can be pulled by mules and horses, Yu Ren has always been unconfident.

He didn't come from a science or engineering degree, and he still couldn't quite figure out the amount of conversion of this force. As a result, he wasn't quite sure what size he needed to make. It can only be roughly estimated. Luckily, his current guests didn't ask him too specifically.

In the end, Yu Ren decided to make the propeller of the small boat first, and then set the size of the big boat according to its size.

As for the steam engine, we will have to wait until the two ships are sold. Not only because of lack of time, but also because of lack of money.

Liu Xi stared at the darkness in the distance, and he felt that in such silent darkness, his head became unusually clear. Some of the formulas in middle school physics class a few years ago began to enter his mind. This helped him design the size of the propeller in front of him. He wanted to write them down, but he didn't have a pen or paper or a lamp.

Yu Ren found a branch and wrote down the formula he thought of on the ground.

When Liu Xi came back, he saw from a distance that there seemed to be no one in the grass shed. Liu Xi was a little worried. He thought that Yu Ren had gone out. This is outside the city, and Yu Ren doesn't know much about the road. It's easy to go to the wrong place with such a black light.

What's more, it's close to the city. But it's also very close to the mountains, and sometimes wolves are infested.

"Brother Ren?" Liu Xi called twice, but no one answered, Liu Xi put the pen and paper in his hand and a bag of food on the table, and hurriedly went out with a lantern to find someone.

As soon as he went out, he saw a figure squatting on the sand outside the hut. When he came in, he was stopped by a pile of wood in front of him, and he didn't see it.

Liu Xi hurriedly walked over with the lantern.

"Stop!" A voice suddenly shouted.

Yoo Hee was taken aback. But then he was relieved. Because the person who called him was indeed Yu Ren. Yu Ren did not go out.

"Just stand there and don't move!" Yu Ren said, walking out cautiously, as if to avoid something on the ground.

Liu Xi thought that there was something like a poisonous snake on the ground, but after looking at it for a long time, he didn't see anything.

Yu Ren walked through the "danger zone" like a flower, and then he relaxed, threw down the branch in his hand, and said to Liu Xi, "Let's go!" ”

Liu Xi led the way in front with a lantern, but finally couldn't help but look back at the land again, but he still didn't see anything.

When Yu Ren returned to the grass shed, he immediately spread out the pen and paper, and wrote down the formulas he had just thought of one by one. Then he drew his designs one by one on paper.

This night, Yu Ren was busy until the second watch before falling asleep. When he woke up, Huzi had already returned, and he also brought breakfast for the two of them.

"How? Did you borrow a boat? Yu Ren asked when he met.

"Borrowed it. As you ask, it's an old ship, very small. ”

"Let's go, let's go!" Yu Ren didn't eat breakfast anymore, so he led Huzi and Liu Xi to see the boat first.

The boat really met Yu Ren's requirements, and he was very satisfied.

After seeing the boat, the three of them went back to the grass hut for breakfast.

After breakfast, Yu Ren took the two of them and began to rebuild the boat according to the drawings he designed.

By almost noon, Tian Jia had also returned. Said that the things have been ordered, and they can get it before noon tomorrow.

Yu Ren was very happy, so the four of them worked together, and before dark, the boat was finally renovated. Now, everything is in place, only the east wind is owed, and only the propeller is waiting.

Early the next morning, Yu Ren went with Tian Jia to get the spiral pulp.

When Yu Ren saw the propeller that he had ordered, he realized that his prior explanation was still not clear enough. The spiral that had just been made was cast with copper and iron, but it was not polished. In this way, the resistance will increase considerably.

There was no way, Yu Ren had to ask the blacksmiths to polish the surface again.

This time, in order to prevent further accidents, Yu Ren stayed in the blacksmith shop.

When the propeller is polished, it will be dark again. Although this copper-iron alloy thing does not look big, it is not light at all. Yu Ren originally wanted to find a carriage and help them send it over. But Tian Jia was unwilling, he went to his house to find a wheelbarrow, put the propeller on the car, and pushed the cart back by himself.

When we got to the place, it was dark again. A few young people couldn't wait any longer. They set up a few fires outside to light up and set about loading the ship with propeller.

It took half a day of hard work to finally load the propeller. Everyone breathed a sigh of relief.

Looking at this device that he had never seen before, Liu Xi asked with some suspicion, "Brother Ren, is this thing really okay?" In fact, this is also a question shared by the three of them. As for whether this thing made by Yu Ren is really useful, the three of them are not very confident. It's just that there is no better way for them to do it at the moment, so they can only let Yu Ren toss. Dead horses should be live horse doctors!

"Okay, no. Let's try it in the water! ”

The four of them then dragged the converted boat into the water.

Sitting on the boat, Huzi and Tian Jia each held a piece of boat pulp in their hands, and Liu Xi sat on the bow of the boat carrying a lantern for everyone.

"Now, let's compare. How about you paddle fast with the paddle, or if I use this propeller to make the boat run faster? ”

"Forget it! It's so dark, let's wait until tomorrow to compete! I'll borrow a boat again tomorrow. Let's make a formal comparison. If you win. I'll go and ask the historian to come and see him. Sun Menghu said.

"Alright then!" Yu Ren said as he reached out and picked up the crank and shook it. To be honest, Yu Ren's heart was also nervous. After all, this was the first time he had designed it. Whether it will succeed or not, he is not very sure.

However, the facts eventually proved that Yu Ren's plagiarism of other people's designs was very clever. The boat was pushed forward by the manual propeller.

At this time, the three of them finally completely convinced Yu Ren. The speed of the boat is significantly faster than that of traditional wood pulp.

"Great. Tomorrow I'll go out and see the historian. Huzi said excitedly.

"Yes, but you'll have to borrow another boat first. Only by contrasting can we show the superiority of our ship. Yu Ren said while rocking the boat.

"Brother Ren, let me try it too!" Tian Jia on the side felt itchy when he saw it.

So, the four of them each itched, and then went back to sleep satisfied.

The next day, several people divided their work again and acted separately.

In the afternoon, the historian really came. This time, he had brought someone with him, a shrewd and capable young man. The young man is the nephew of Shi Yuanwai, named Shi Youcheng. Shi Youcheng helped Shi Yuan take care of business outside the city of Nanjing. Therefore, I have a good understanding of the situation in Nanjing.

The historian took his nephew with him, and the meaning was obvious. That is: Don't think that we outsiders are all wronged, I know a lot more about Nanjing than you. In fact, in the final analysis, this historian will still be skeptical of the kind of ship that Yu Ren boasted about to him. And his nephew, after hearing his uncle's account, was even more unconvinced.

In the distance, the historian saw two small boats parked by the river. There was no ship pulp on one of them.

"Is that the boat you're talking about?"

"Yes." Yu Ren was by the side of Shi Yuanwai, and from Shi Yuanwai's tone, Yu Ren could clearly feel that he did not trust him.