The Great Qin Empire---Qin Li

It has been two years since the 21st year of the reign of King Qin, when Yuan was awarded the title of a public official for making the "Anlu Pestle" and was noticed by the county engineer, who asked him to work as a craftsman in the county.

In the past two years, Yuan and his wife have settled down in the county. From the initial novelty and uneasiness to gradually getting used to it, life in the county is much richer than in the small village. They don't have to watch others eat. They can get a fixed annual salary. With the one hundred acres of land that Zhong has been helping to manage, the family can be considered to have no worries about food and clothing. They are already rich enough to eat meat every other day.

Yuan is satisfied and feels that this is what he has been pursuing in his life.

The only trouble is that as a craftsman in the government, he can't make whatever he wants. He must receive official documents and get the "Book of Life" for production permission before he can start work. Without this thing, he can't work, otherwise, including Yuan's superior engineer, will be fined two grades.

Even when Heifu asked Yuan to help make the stone wheel for squeezing sugarcane pulp, he had to find time to do it during his rest days, and he had to prepare all the materials by himself, and he didn't dare to take a piece of wood from the workshop. Because not long ago, a craftsman was severely punished for stealing materials from the workshop to do private work, and became a slave without freedom.

In addition to the stone wheel, when Heifu was about to leave Anlu in early January, he asked someone to bring a message to Yuan, asking him to take a leave to go back to his hometown for a few days. Yuan thought something had happened, and after hurriedly returning to the sunset, he found that Heifu had prepared a tree's wood for him, hoping that he would make something - something that had not yet appeared in this era!

Yuan was very skilled. Heifu only described the general appearance of the object, and he had an idea in his mind. As the axe and the saw danced quickly, the plane pushed out the curled wood flowers, and the copper nails and wooden zither were placed in the right place, the machine that Heifu needed gradually took shape: a small water wheel no taller than four feet...

Heifu asked Yuan to put the small water wheel on the ditch beside their field. When the brothers released water into the rice field, the horizontal board of the small water wheel was impacted by the water flow, driving the entire water wheel to roll counterclockwise. As long as the water flow did not stop, it would not stop.

"This thing is interesting."

Although Yuan thought it was interesting, he did not take it seriously and did not think it could have any practical use. As Heifu went to the county town, Yuan continued to devote himself to his daily work for the next month and forgot about this matter.

Until one day in early February, when Yu was teaching two apprentices to make a treadle, the county engineer called him over with a serious face and handed him a transfer order from the county. Yu felt that something was wrong...

"The county wants to transfer me to Ying County?"

Yu was a little confused. Although he was reluctant to give up his peaceful life, he dared not disobey the county's order. Under the nagging of his wife, he packed his bag and did not take any extra things. He only took the ruler, square, plane, saw and other tools that stone and wood craftsmen needed to eat.

"As long as you have these, you won't starve to death wherever you go, don't worry."

After patting his saddlebag and comforting his wife, Yu set off on his journey. This was the first time he left Anlu County in the thirty years since he was born.

While tossing and turning in the pavilion on the way, Yu also secretly thought: "Is the transfer of me to the county related to Heifu?"

Because two years ago, it was Heifu who gave him a big gift and let him go to the county.

Yuan thought that she would meet Heifu only when she arrived at the county town, but she never expected that Heifu was waiting there just after they crossed the wide Han River crossing.

"Brother-in-law!"

Heifu waved to the dusty Yuan from a distance. There was a young man who looked honest beside him, but the tattoo on the young man's face surprised Yuan a little. Heifu was now an official doctor, so why was he staying with a tattooed prisoner?

It turned out that Heifu had not been idle these days. He volunteered to go on a business trip to Jingling County, two hundred miles away, to determine the number of soldiers to be recruited in Jingling County, and visited Huaimu's widow and two brothers by the way.

He conveyed Huaimu's last words to Huaimu's widow, left ten taels of gold and said goodbye. As for Huaimu's two younger brothers, they have also regained their freedom. The younger uncle inherited Huaimu's title of "doctor", but the middle brother Sangmu got nothing and was worried about what to do in the future. Although Sangmu himself did not commit a crime, he once tried to escape, so his face was tattooed with ink. It was extremely difficult for him to make a living in other industries except hiding his official position.

Seeing that he looked very similar to Huaimu, Heifu couldn't help but miss his old friend, so he simply let Sangmu go back to Ying County with him.

"I just need a driver to drive the car."

Heifu did not discriminate against Sangmu, and patted him and said, "Sangmu said he can drive an ox cart. After going to school in the county for a month, he should be able to drive a horse carriage."

Yuan didn't say much, but the ink on Sangmu's face still made him feel glaring, because in Yuan's subconscious, those who break the law must not be good people. When they rested in the pavilion by the Han River, he finally found an opportunity to ask Heifu alone.

As a result, Hei Fu frightened Yu out of his wits with just one sentence!

"I told the county lieutenant that as long as you give your brother-in-law manpower and money, you can transform the treadle that still needs human operation into a magical tool that can operate automatically without human hands, which can save ten times the manpower!"

Yu's eyes widened, and he murmured honestly: "Is there really such a device? Why don't I know about it?"

...

Yu couldn't eat again. He was worried about this "impossible task" that Hei Fu had taken on for him.

Hei Fu was not worried, but asked Yu to follow him to the bank of the Han River in the evening.

"The Han River is so wide that it cannot be swam; the Yangtze River is so long that it cannot be thought of."

The boatmen who paddled their boats to transport pedestrians still sang the ballads that had been circulated hundreds of years ago. Under the setting sun, the water surface dyed red by the sun was endless.

"Water flows through the earth, including the Yangtze River, Huai River, and Han River." The Han River, along with the Yangtze River, the Great River, and the Huai River, is listed as one of the four major water systems of this era. It is more than two or three times wider than the Ru River that Heifu once crossed.

There was a group of young people playing naked by the water. Unlike the landlubbers in the north, they have been swimming in and out of the water since they were young and have learned to swim well. These young people swam happily, either down the river or upstream. Those who were in good shape could even cross the Han River back and forth. They would be the main targets of the three thousand "shipmen" in Nanjun.

Heifu also saw waves of women washing clothes, waving their mallets by the water, pounding and washing clothes while loudly talking about family matters. Some old women were washing baskets and earthenware jars in the river...

Hanshui is the mother river of the people of Nanjun. Tens of thousands of families live on both sides of the Hanshui River, relying on the Hanshui River to irrigate their fields and relying on the inexhaustible aquatic life in the river to supplement their meat.

However, in summer and autumn, the Hanshui River is not as gentle as it is now. It is the "Hanshui River" that everyone fears. Floods occur every year, destroying some fields and houses in low-lying areas, making residents by the water tremble with fear.

"At that time, the real Jing River will be so big that you can't tell cattle and horses between the two banks and cliffs."

After walking more than a hundred steps along the Hanshui River and saying a bunch of seemingly unrelated words, Heifu asked Yu: "But brother-in-law, have you ever thought that if this Jing River, which is faster than cattle and horses, can also be used to work for people like livestock, how great it would be!"

"Control... Jing River?" Yu couldn't imagine.

"I dare not say control."

A good swimmer is prone to drowning, so we should still be respectful of nature. Hei Fu smiled and said, "I just hope that He Bo will share a little of the wasted power of flowing water with us, that's all."

Yuan still thinks Hei Fu's idea is whimsical. They can scoop water from rivers to drink, and they can build water conservancy dams to separate runoff and let it flow into dry fields, but let the water flow directly like cattle and livestock to help people work?

"That's something that only He Bo, Xiang Jun and other water gods can do. How can humans have the ability of water gods?" Yuan questioned. The idea is good, but he doesn't think that such a thing can be done with just human power.

Hei Fu shook his head and said, "No, I heard that in ancient times, people also thought that fire was a gift from the gods, until a sage named Suiren made fire with his own hands. Nowadays, any child can make fire with flint and a knife. Does anyone still think this is a miracle?"

He knew that the history of human use of energy, that is, the history of human understanding and conquest of nature, the first stage was the discovery and use of fire; the second stage was the use of natural power such as animal power, water power, and wind power; and then came fossil fuels, electricity, and atomic energy...

Today's China is still in the early stage of the second stage. It has fully utilized the power of livestock, but the use of water power and wind power is still extremely limited. On the land of China, thousands of streams and rivers rush into the sea, and their potential energy is wasted, and no one thinks of using it. Only countless slaves and common people are still desperately using their own labor to do those heavy jobs. They are miserable under such heavy labor, and many people do not live beyond the age of thirty or forty...

So Hei Fu thinks that it is time to upgrade technology from 2.1 to 2.2. The time traveler should not only make up for those historical regrets, but also liberate productivity to the best of his ability, and liberate more people from monotonous heavy work, which is also his historical mission.

And all this started with this conversation by the Han River.

"Brother-in-law, do you still remember the small water wheel you and I made in Anlu?" Hei Fu said.

"I remember." But Yuan only regarded it as a toy to amuse children.

Hei Fu pointed out: "It is actually a sharp tool for using water power. The water flow hits the horizontal wood on the water wheel, making the water wheel rotate day and night. If a wooden shaft is installed on the water wheel, and a wooden pestle is placed on the wooden shaft... In this way, there is no need for people to step on it with their body weight. Wouldn't the wooden pestle move by itself under the drive of the water wheel?" Seeing that Yuan showed a look of sudden enlightenment, Hei Fu knew that he finally understood, so he said: "This is the magic weapon I mentioned that can pound ore and grain by itself without human power." "This thing moves with water, so how about calling it a water pestle?"