Outside the Mingde Gate of Chang'an City, here is a straight cement avenue, and at the same time, it is also the cement road from Chang'an to Songzhou. After the cement road came out of the Mingde Gate, it went straight to the south, and it was not until three miles away that it began to turn with the terrain, and in this turning place, there was an extremely important standard building.

Chang'an Observatory, or Meridian Observatory. This observatory was originally proposed by Li Su and designed by Li Chunfeng himself, which was originally built under the auspices of Yuwen Hu, but because of the military school, it had to be handed over to others, and it collided with the construction of the military school, resulting in a shortage of workers and materials, which made the construction very slow, and it was not until the day of the start of Li Su's marine life exhibition that the construction was finally completed.

Li Su drove out of the Mingde Gate, the purpose was to come to this observatory, the distance of three miles almost in a flash, when the straight cement avenue began to turn, and in the direction directly opposite the Mingde Gate, a fortress-like building rose from the ground. This is the Chang'an Observatory.

The main body of the observatory is a cylinder like a turret, and the top is a hemispherical shape like a pot lid, and the whole body is built with the best cement and steel bars.

The color of the observatory is also very interesting, with white on the east side and black on the west side, representing day and night, respectively, and at the junction of black and white, there is a metal wire made of bronze that extends from the wall of the main building to the ground. It is located right in the middle of the concrete pavement, and it extends forward for dozens of meters until it disappears under a high platform.

This high platform in front of the observatory is even more interesting, originally when the observatory was built, there was no such high platform, and even this high platform has just been built, and the cement on it has not yet dried. The reason for the construction of this high platform. In fact, it is to put one thing on it, and that is the skeleton of a whale.

After the Shangyuan Festival, all the whale meat was eaten by the people of Chang'an. However, the bone frame was preserved, and even Li Su had instructed the cooks in advance to try not to hurt the bones when cutting the meat. So the skeleton of this whale is very well preserved.

Originally, according to Li Su's meaning, he wanted to build a cement platform on Suzaku Square, and then put the whale skeleton on it, in order to commemorate the significance of the marine exhibition, and in his opinion, such a complete whale skeleton itself is an incomparable work of art.

It's a pity that Li Su's advanced aesthetic vision will not work in the Tang Dynasty, as soon as his suggestion came out, not only Li Shimin frowned, but the civil and military ministers below were even more opposed. After all, Suzaku Square is a place of great political significance, and it has a sacred and solemn meaning in itself, if you suddenly put a bone shelf on it, what kind of system will it become, and this is too unlucky!

Whereas, all ministers are against. Li Shimin naturally rejected Li Su's proposal. But Li Su is not discouraged, since you have no vision, then this good thing will belong to me, if you don't let me be released in the square, I will be put at home, think about putting a whale skeleton in your own garden, it will definitely be a very face-saving thing in the future life.

It's a pity that his ideas above are good. But it didn't work, because whether it was Wenxin or Xijun, even Wen'er and Hua'er, who had always been well-behaved, were against it, on the grounds that they would not dare to go to the garden to play in the future if they put such a scary thing at home.

Well, Wen Xin's opposition is very reasonable, after all, the family is not Li Su alone, Wen Xin and they are all family members, and they are also in charge of family affairs, so this matter is not within Li Su's authority, so the fight where he put the whale skeleton at home was also declared bankrupt.

In desperation, Li Su had to give away the whale skeleton, but unfortunately he asked Li Ke and his brothers, as well as Cheng Huailiang and Li Jingye, a group of fox friends and dogs, but none of them were willing to ask for this thing, after all, in their aesthetic view, they really can't see what artistic value this skeleton has?

Li Su, who felt that he was a little tall and widowed, was very sad and angry, and he was originally kind, but he couldn't appreciate it at all. Fortunately, at this time, someone took the initiative to find the door and ask the whale skeleton to leave, and this person was Li Chunfeng, who lived in the observatory. Li Chunfeng is an astronomer with a forward-looking vision, but also a great mathematician, generally this kind of person is different from ordinary people, Li Chunfeng and others may be different from his aesthetics, which he just happened to be a bosom friend with Li Su, I heard that the other party went around selling his whale skeleton, Li Chunfeng immediately came to the door to ask for something to go, and then placed it in front of the observatory.

When Li Su arrived at the observatory, the first thing he saw was this whale skeleton with his head and tail swinging, if it was in normal times, he would definitely get off the horse to appreciate this exquisite work of art, but unfortunately today he was thinking about the incident that Li Chunfeng sent someone to inform him, so he didn't stop under the high platform at all, rushed to the door of the observatory and jumped off the horse and rushed in.

"Chang'an, 0 degrees; 34.33 degrees north latitude. Luoyang, 3.32°E, 34.27°N......"

As soon as Li Su broke in, he immediately saw Li Chunfeng and several officials of the Taishi Bureau recording the longitude and latitude of several cities while reciting, and as soon as Li Chunfeng saw Li Su coming in, he immediately put down his pen and stood up and said with a smile: "His Royal Highness King Qi Wait a while, the longitude and latitude of several cities around Chang'an are about to be checked." ”

Although Li Chunfeng was anxious, he also knew that Li Chunfeng and they were calculating, and there was no mistake in the slightest, so he didn't bother them, he found a seat and sat down, and after a while, Li Chunfeng and they finished calculating, and at this time, everyone's faces showed a look of ecstasy.

"Your Highness, great joy, we calculated the latitude and longitude of several cities around Chang'an, and then measured it with a newly made sextant, and then compared the two results, and finally found that it was almost identical, so it seems that this sextant has finally been developed!" Li Chunfeng grabbed two pieces of paper full of number symbols, and ran to Li Su with his hands and shouted.

At the beginning, Li Chunfeng and Li Su lost the bet, and they had to do two things for Li Su, the first was to help Li Su formulate the latitude and longitude of the earth, and the other was to make a sextant to determine the latitude and longitude of the surveyor. The first thing is that for Li Chunfeng, there is no difficulty at all, just some calculations that are not too difficult. The second thing is a little troublesome, starting from Dengzhou, Li Chunfeng has been busy with this matter, but unfortunately it has not been successful, and then Li Chunfeng returned to Chang'an, and has not put down the development of the sextant, and now after nearly two years of research, the sextant has finally been made.

In fact, the sextant had been made as early as a year ago, but Li Chunfeng did not alarm Li Su at that time, after all, this thing was only theoretically feasible and had not been measured on the spot, so he made the sextant, and then sent several groups of people to the surrounding cities of Chang'an, and measured the latitude and longitude of these cities with the sextant, and then sent the results back to Chang'an again.

This morning, Li Chunfeng finally received the results that were sent back, and then calculated the previous measurement data of several cities to obtain the actual longitude and latitude of several cities, and compared this data with the measured data, and the error was extremely small, which also proved the accuracy of the sextant measurement.

"Quick~ show me the sextant!" Li Su also rubbed his hands excitedly, with a sharp weapon like a sextant, he no longer had to worry about the problem of getting lost at sea, and this also marked that the prelude to the great era of navigation he was looking forward to was finally about to open!

Seeing Li Su's eagerness, Li Chunfeng smiled, turned around and picked up a strange instrument from the table next to him, the palm of two adults was the size, and the whole body was made of brass, which looked extremely beautiful. I saw that the main body of the sextant was a 60-degree fan, with a scale on the side of the arc, and a telescope and a translucent mirror in the two radii of the fan. It's just that Li Su fiddled with it for a long time, but he didn't know how to operate, but he didn't really care about this, as long as this thing was easy to use.

"Brother Chunfeng, there shouldn't be any difficulty in manufacturing the sextant, can it be mass-produced now?" Li Su asked impatiently, he is now eager to let all the sea ships of Datang use this thing, after all, with this magic weapon, the maritime merchants will also have a sharp weapon to promote life, and the courage to sail on the sea in the future will be more sufficient, and the opportunity to open up new routes will increase accordingly.

However, after hearing Li Su's question, Li Chunfeng showed a wry smile, bowed down and replied: "Your Highness, the production of the sextant is no problem, but the problem is the operation of the sextant, although it does not have high requirements for the user, but at least it must have a certain mathematical foundation, and can do some simple calculations, but now among the people who sail on the sea, there are few such people, so even if there is a sextant, they will not use it!" ”

Li Chunfeng's remarks can be said to hit the nail on the head, Li Su has never attached much importance to the issue of education, and in his view, as long as the people become rich, the problem of education will naturally be solved. However, now that the sea trade wants to develop, it has put forward a requirement for the cultural level of the crew, and if it wants to solve this problem, it seems that it is necessary to educate a group of crew members who know arithmetic.

Thinking of this question, Li Su was silent for a long time, and then he said to Li Chunfeng: "Brother Chunfeng, I am about to leave Chang'an, but the sextant is very important, so you first discuss with Wang Zihao in my house, let him open a factory first, specializing in the production of sextants, as for the training of users, this is up to me to solve, but you first send some people who can operate the sextant to me!" ”

"This is no problem, I just want to send a few disciples to the sea to experience it, just let them go with you, as for how to arrange, all listen to His Highness!" Li Chunfeng is also very bold, he vaguely feels that he is helping Li Chun create a great era! (To be continued.) If you like this work, you are welcome to vote for recommendation and monthly passes, and your support is my biggest motivation. )

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