Hearing Dai Yan's statement, Zou Yan didn't react yet, and Prince Tian Bijiang was the first to be interested, and he asked, "Dare to ask the prince how to measure the earth?" ”

"Since the earth is a sphere, the size of the earth is the size of the earth's surface area. Pen × fun × Pavilion www. ｂｉｑｕｇｅ。 infoTo know the size of the earth's surface area, you need to know the size of the earth's radius. To know the radius of the earth, it is naturally impossible for us to go deep into the earth's crust and measure the length from the earth's crust to the surface.

If you want to know the radius of the earth, you only need to know the circumference of the earth. To know the circumference of the earth, we can choose to measure its elevation angle with the sun at noon. Then walk a long enough distance due north from this place to reach place B, and then measure the elevation angle between place B and the sun.

Knowing the distance between A and B, and then measuring the elevation difference between A and B and the sun, you can easily get the circumference of the earth. In this way, we can know the radius of the earth, and the size of the earth's surface. ”

The method that Dai Yan talked about was actually the method of measuring the length of the prime meridian by the monks of the later Tang Dynasty, and this principle was very simple for Dai Yan.

However, if you do do this, the results will inevitably be imprecise. From modern knowledge, we can know that the earth is not actually a regular sphere, and this is not only the reason why the terrain on the earth's surface is undulating and uneven. In practical terms, the Earth itself is a slightly flattened sphere.

However, when viewed from space, it is still a regular sphere. Therefore, in the case of not needing to be particularly realistic, it is indeed possible to know the size of the earth in this way.

As soon as Dai Yan put forward this idea of measuring the earth, Prince Tian Bijiang couldn't wait to ask Zou Yan: "Mr. thinks that the method Ziyan said can measure the size of the earth?" ”

Zou Yan thought for a moment, and then replied: "Gongzi Yanzi's method of geodemetry is indeed exquisite and abnormal!" He already knew that the earth was spherical, and in this way, he could indeed know how big the earth was! ”

Although Dai Yan only briefly expounded the principle of geodesy, Prince Tian Pijiang attaches great importance to it! He bowed deeply to Dai Yan, and then said: "Heaven and earth, the things of the gods, are beyond the reach of extraordinary people!" However, Childe was able to indirectly measure the size of the earth through his own wisdom! Childe is really a god! ”

Don't blame Tian Bijiang for having such an attitude. In the modern society that Dai Yan traveled through, because of the actual communication brought by developed means of transportation such as airplanes and high-speed railways, and the high-speed information communication brought by the Internet, the whole earth has become smaller and smaller in the eyes of people, just like a global village.

However, in this era, a country with a radius of thousands of miles, which was only a province in later generations, is now a large country in the whole world! And people realize that the whole world is Kyushu, which is almost the limit of the understanding of the world for most knowledgeable people in this era.

The state of Qi is such a big country, and its rulers are by no means like the Manchu Qing Dynasty in later generations, a country that enlarges the literal prison and closes the mind and closes the country to close off the people. Although the country is only a small province, its rulers are very open.

Ideologically, it can be tolerant of all things. In terms of employing people, we can reduce talents without sticking to one pattern. In terms of territory, Qi hopes to expand aggressively.

Qi was the first country in Chinese history to truly go to the sea. More than a hundred years ago, the state of Qi was the same as the state of Wu, which was once powerful in the south. On the surface of the Yellow Sea near Langya, the first naval battle in Chinese history broke out!

The fact that the Qi State was able to become the prosperous country of Haidong in the world now relied on its continuous eastward expansion to absorb the remnants of Dongyi. In today's era, the territory of Qi has truly expanded to the seaside, and the entire Shandong Peninsula is ruled by it.

Further expansion, the Qi state was further expanded to the west, with the powerful states of Zhao and Wei, and to the south, there were the states of Song and the difficult states of Chu. With the expansion in both directions, the Qi State suffered serious setbacks. In the eyes of Qi State, the only hope is to expand to the north.

Judging from the major strong enemies around the Qi Kingdom, only the Yan Kingdom in the north is a relatively soft persimmon.

However, there is still one direction that Qi has not given up, and that is the sea. The territory of Qi is surrounded by the sea on three sides, and it is definitely a lie to say that it does not want to use the sea. However, Qi Guo didn't know what was going on overseas, and he didn't have much interest in the ocean.

Now that Dai Yan has the skills of geodesy, isn't it easy to know the geographical situation overseas? This is very beneficial to Qi's overseas expansion!

Prince Tian Bijiang thought so in his heart, but when he learned that Dai Yan was courteous to Dai Yan in astronomy and geography, there were more important reasons!

As far as Tian Pijiang is concerned, he is not the king of Qi yet, and he is interested in overseas geography, but not much. And what he is really interested in is the immortal mountains overseas, as well as the legendary elixir that can make people immortal!

He asked more and more respectfully towards Dai Yan: "Dare to ask Gongzi, since you have the divine power to measure the earth, you should also know the situation of overseas immortal mountains?" I wonder if the legendary elixir that can make people immortal exists in the overseas immortal mountains? ”

Dai Yan coldly heard such a question, and immediately cried and laughed. He directly cut off Tian Bijiang's thoughts: "In my opinion, on the earth, the sea divides the continents into independent pieces. There may be majestic mountains on the earth, far beyond the famous mountains and giant mountains in China, but there is no real immortal mountain, and there are no immortals in the world, let alone an elixir that can make people immortal! ”

"How can there be no elixir in the world? In ancient times, Chang'e got the medicine of immortality and ran to the moon to become an immortal! There must be immortal mountains on the earth, and there must be elixirs that can make people immortal! Tian Bijiang said sharply, and his last sentence was even a little hysterical.

Dai Yan was a little puzzled by Tian Bijiang's performance, but Zhao Yong was clear about it.

Tian Pijiang is the prince of Qi, and he Zhao Yong is the prince of Zhao. For them, the true rulers of great powers, the quest for eternal life has always been the pursuit of their hearts!

In history, it was not only the Qin Emperor and Han Wu who sent Fang Shi to the sea to look for the elixir! The first to do this kind of thing happened to be the Qi people and Yan people in Linhai. And now, King Qi's health is deteriorating, and not long ago, he privately sent a fleet to the sea to seek immortal medicine!

Zhao Yong came to the Qi State, naturally he did not simply come to the Jixia School Palace to study, the most important purpose of his coming to the Qi State was to explore the secrets of the Qi State. Although the King of Qi sent Fang Shi to the sea, such a matter was very secret, Zhao Yong still found out the news of the cut.

So he reminded Dai Yan in private, asking Dai Yan not to continue to anger Tian Bijiang on this issue.

Regarding Zhao Yong's suggestion, Dai Yan did not take it to heart. He said directly to Tian Bijiang: "Prince, in this world, there is no immortal!" There is a limit to human life, and when the time comes, people will inevitably die! And this is the law of nature in the world.

People live in the world, and they can only follow the rules of heaven. If you violate the rules of heaven, you will definitely not end well! ”

He said this to show his attitude, and it was his warning to Tian Bijiang, as for whether Tian Pijiang could listen to it or not, it was none of his business!

After that, he didn't want to say anything more. He was already a little tired from today's debate, and he wanted to take his leave and go back.

However, when he was about to leave, Tian Pijiang deliberately kept Dai Yan and said to him: "Didn't Gongzi want to lecture in my country's Jixia School Palace before? With the general knowledge of a childe and a god, this kind of request is naturally no problem! I will ask my father on the same day that I will confer the honorific title of Doctor on Gongzi, and hire Mr. as a bachelor of my Qi Guojixia Academy! ”

Doctor Xia, who is a prince in the Song Kingdom, and Dai Yan, who has the honor of a feudal monarch, naturally doesn't care, but Dai Yan attaches great importance to officially becoming a bachelor in Jixia Academy. Because this means that Dai Yan has officially entered the big stage of a hundred schools of thought, and he can compete with hundreds of schools of thought and scholars from all over the world!

The Mo family giants Qi Jiaozi and Zou Yan, who were sitting opposite Dai Yan, all had some bad feelings in their hearts. Especially Zou Yan, originally he was the youngest bachelor in the entire Jixia Academy, but from today on, the title of the youngest bachelor will be taken away by Dai Yan!