After leaving Fuzhou for more than half a year, Zhao Jiaren returned to Fuzhou City again, and what he saw was still the same cityscape. It's just that the city hasn't changed, and the people in the city still change. For example, the number of people in Zhao Jiaren's school has increased by more than 3,000.

"Hurry up!" A group of people moved the furniture from the prison residence to the shipyard base in Mawei. Of course, the furniture is all Zhao Jiaren's furniture, and those that were originally in it have not moved at all. Zhao Jiaren, who was standing in the courtyard, suddenly had a trace of nostalgia, even if he basically did not work hard in his own business in the past three years, that is, he did not care about supervising taxes at all, but this position did have advantages that Quanzhou Zhizhou could not match.

It turns out that the so-called number one feels so good, the power is in hand, and people from all walks of life must obey the will of the number one. Touching the bypass, Zhao Jiaren was finally able to imagine the characteristics of the system outside the Great Song Dynasty.

The new Fujian Road Prison has not yet arrived in Fuzhou, and in theory, Zhao Jiaren can wait or not. He still chooses to wait, there are still many things to do in Fuzhou.

"Congratulations to the principal." At the school base in the city, the class leaders took the lead, and everyone else followed. The atmosphere looks very lively.

Zhao Jiaren waved his hand, "Thank you." However, there are many important things at this time, and the most urgent thing is to recommend a reliable, unassuming, and hard-working person in each class. I have a craft that I need someone to learn. ”

Upon hearing this request, all the cadres became excited. Over the years, everyone has learned a lot of knowledge, especially a lot of crafts. After having a craft, you can rely on your craft to eat, which is not only a matter of this life, but also can pass on the craft to children and grandchildren, so that they will not live without food.

"Headmaster, let's sort out the level of reliability before you leave. We did, how reliable is it to be this time? Li Hongjun, the leader of the first class, asked.

Zhao Jiaren Zhengse said: "This craft is not allowed to be passed on for thirty years, according to this standard." ”

The next day, ten students were sent to Zhao Jiaren. From his teens to his thirties, he is a reliable member of the family who came to Zhao Jiaren. The contract was given to them, and the study committee guided them to figure out the contents of the contract one by one. Thirty years of not being allowed to spread the word means that the product must be purchased within thirty years. In this era when forty years old is considered to be entering old age, thirty years of security means that this life is stable.

Another half a month has passed, and the new Fujian Road Tidian Prison has not yet arrived. In Zhao Jiaren's factory, three of the ten people said they couldn't do it. Zhao Jiaren can fully understand their thoughts, burning glass is a very terrifying thing. The inside of the glass furnace is thousands of degrees Celsius, and the staff also have to wear thick anti-scald clothing and use long steel bars to constantly stir the glass solution in the furnace. When you sweat profusely, you have to wear thick clothes, which is really like being in hell. Everyone basically insists on changing shifts for half an hour, and if you exceed this time, you really can't stand it.

"Twenty more!" Zhao Jiaren ordered.

However, stirring is extremely useful, and the chemical reaction of calcium and sodium glass will form bubbles. If you want to make clear glass that can be used as a mirror, you must constantly stir it to release as much air bubbles as possible from the viscous melt. The high-intensity working environment is not to make things difficult for anyone, Zhao Jiaren has fully absorbed the experience of later generations and made a lot of improvements to the working conditions. In Europe, when a glass mixer tied himself to an iron pillar in the middle of a large glass pool, it was not like hell, but he was actually in hell.

The trainees who used urea to make ammonia said that this could be used as torture against the enemy in the future. If it weren't for Zhao Jiaren's order, everyone would not have thought of doing this anyway. Zhou Xing, who made steel molds two years ago, said there was no pressure on the blacksmith department.

By 18 February, the first batch of silver-plated glass, which was 10 centimeters long and 6 centimeters wide, had finally been shipped. All the people who got the glass mirrors were amazed, they never expected to be able to see their faces so clearly. Compared with this kind of glass mirror, the white copper mirror is not enough to see at all.

On 19 February, on a sunny day, on the shore of Langqi Island outside the mouth of the Minjiang River, a group of students who had graduated from elementary subjects in mathematics and geography set up sextants. The theory of this instrument is simple, but it cannot be operated without a mirror.

Below the sextant is a level, next to which is a horizontal corona floating on the water. Four years have passed since the establishment of the school, when the position of the coronal hand at noon was recorded daily. Seven or eight blackboards were set up next to it, and the data sheet with Cos was ready.

Whether it's simply following the crowd or drawing conclusions through your own thinking. The students who were able to come here firmly believed in the theory of the solar system told by Zhao Jiaren, and as the hands on the corona approached the noon point drawn little by little. Everyone's emotions became more and more excited.

Many people have already used the sextant, which has a fan-like shape and includes a small telescope, a translucent and semi-reflective fixed plane mirror, that is, a horizon mirror, and an active mirror linked to the index, that is, the index mirror. When used, the observer holds a sextant and rotates the indicator mirror so that the celestial objects that appear at the same time in the field of view coincide with the sea horizon. The altitude angle of the celestial body can be read out according to the angle of the indicator mirror. Substituting this angle into the calculation formula, the latitude can be calculated.

The lens is polished with highly transparent crystal, but the mirror must be made of a glass mirror, and it is not possible to test it until now because soda ash cannot be obtained, so there is no way to create a highly transparent reflection. Now that all the conditions are in place, it is finally time to test.

In the 21st century, Zhao Jiaren has long used all kinds of sextants, and this operation is done by the students, and he does not want to compete for this great joy. In order to gather this group of scientific and technological personnel of the highest level in the world in 1260, Zhao Jiaren invested a lot. Looking at the excited expressions of these people like children, Zhao Jiaren only sighed in his heart. By determining latitude and longitude, you can create a high-precision map, which is completely different from traditional maps.

"Headmaster, it's almost noon." The squad leader Li Hongjun came to ask Zhao Jiaren, who was standing on the seaside and looking into the distance.

"Let's test it." Zhao Jiaren said flatly.

Li Hongjun himself lacks a concept of latitude and longitude, but he firmly believes that Zhao Jiaren has a scholarly knowledge, so he firmly believes in the theory proposed by Zhao Jiaren. For this reason, Li Hongjun was reluctant to get together with the group of people crowded next to the sextant. He could feel the difference between himself and the people, the guys were really happy to be able to observe, they were really happy with what was calculated. Li Hongjun really only wants the results after observation.

Since he didn't want to join in the fun, Li Hongjun stayed with Zhao Jiaren, and he asked, "Principal, why do you use the Fuzhou meridian tentatively?" ”

"Because the capital of our Great Song Dynasty is Bianliang, not Lin'an. There is a viewing platform in Bianliang, and the meridian that passes through the Bianliang viewing platform should be the prime meridian of the Great Song Dynasty. Everything else is tentative. At such a purely scientific moment, Zhao Jiaren's tone was flat. Where to be the prime meridian is a political issue, not a scientific one.

"That'...... You'll have to fight a lot of battles to be sure. Li Hongjun sighed.

Zhao Jiaren was speechless for a while. Yes, if you want to go back to the old capital, you have to go through a lot of wars, so Zhao Jiaren doesn't want to mention this problem at this moment. However, since Li Hongjun proposed it, Zhao Jiaren asked: "Hongjun, do you think you are competent to let you command the war now?" Or who among our brothers is more capable of fighting. ”

"Who else is our opponent at sea?" Li Hongjun asked puzzled.

"It's not at sea, it's on land." Zhao Jiaren asked seriously.

Li Hongjun hesitated for a while, and finally replied: "I haven't fought this ......, I really don't know." ”

"It's noon, don't say anything, let me concentrate on observation!" There was a loud shout from the sextant in the distance. There was silence over there.

Zhao Jiaren had something in his heart, and he was silent. At this moment, there was no discussion in the observation area other than the atmosphere of science.