Steel Dynasty - Chapter 281

[Chapter 281 Globe]

After a night of hangover, Xiao Ming’s head still hurt when he woke up early the next morning.

Today is the first day of the Lunar New Year. According to custom, it is the time to visit relatives and friends. If he was in Chang’an, he should have visited everywhere.

However, in Dayu Kingdom, if there is no important matter, the vassal king is not allowed to leave the fiefdom, especially since Xiao Ming is still responsible for guarding the border, so he cannot leave his post without permission.

Now that New Year’s Eve has passed, for Xiao Ming, the first thing to do during the new year is the sailing of Galen’s ship.

Arranged to secretly spread the drama to the people, he went to Bowen Academy. Others could rest during the New Year, but Yue Yun could not rest.

After all he would be the leader of the three Galenic ships.

“Your Highness, is today the last lesson before going to sea?”

Yue Yun was waiting in the school in the morning.

Xiao Ming nodded. There were two reasons why he asked Yue Yun not to go to sea for the time being. One was that the artillery had not yet been put on the ship, and the other was that Yue Yun still lacked the most important lesson in navigation – how to locate one’s position at sea. .

There are only three people in the school, one is Yue Yun, and the other two are two sailors who are better at learning among the sailors this time. The position Xiao Ming gave them at sea is navigator.

As the name suggests, the duty of the Navigator sailing battleship is to locate the ship and guide the Galen ship to the right direction.

Sitting down in front of the three of them, Xiao Ming said: “You can’t learn all these things in one class. Remember, the things you have to learn below are very complicated, so cheer up, otherwise you will probably get lost. You will never come back from the sea.”

Yue Yun and the others nodded heavily after hearing this, because Xiao Ming had never been so serious in school.

At this time, Xiao Ming stretched out his hand, and a royal servant came in. He was holding a spherical object in his hand. There were sticks running through the middle of the spherical object, and the bottom was the land.

“You once asked me what this world is like, and now this world is right in front of you.” Xiao Ming pointed to the globe on the table.

This was what he had been preparing during the Chinese New Year. This globe was made of pure wood and was polished very smooth on the outside. The longitude and latitude of the earth and the world map were marked on the globe, especially the vertical and horizontal navigation routes, and even where there were reefs. .

The special products of each region are also marked on the map, such as corn, cotton, sugar cane, gold, etc.

“Your Highness, is this the globe you are talking about?” Yue Yun and the others looked shocked.

What this globe presents is definitely a subversion of their thinking.

Xiao Ming nodded. The diameter of this globe was one meter, and it was enough for Xiao Ming to draw a map of the world on it.

In order to draw this map, he destroyed more than a dozen globes. When this one was a little more perfect, he used it directly, otherwise he would not have waited until now to teach Yue Yun this knowledge.

Xiao Ming pressed his hand on the globe, and the globe began to rotate. Pieces of ocean and land flashed in Yue Yun’s eyes.

“Let’s start from the simplest. First of all, you have to know which oceans and which lands the world is divided into.” Xiao Ming began to teach Yue Yun the knowledge of the four oceans and seven continents.

It can be said that his current education is basically a cramming education. There is no other way. Some things can only be memorized by rote, and this is his strength.

While talking, Xiao Ming showed the locations of these regions on the globe and gave detailed information about every landmass in the world.

After popularizing world geography knowledge, Xiao Ming got to the point.

“Now that you know that the world is very big and there are many countries, it’s time to teach you how to position yourself at sea.” Xiao Ming said.

Yue Yun and the other three have become very humble now.

The study during this period of time made them feel like they were just like frogs in a well, and they no longer had the arrogance they once had.

“This is a quadrant.”

After the globe, Xiao Ming took out the same item necessary for navigation in this era, the quadrant. The real name of the quadrant in his hand is the Davis Quadrant.

This quadrant was invented by the British navigator Davis at the end of the 16th century and was used to measure the latitude of the earth during navigation.

According to records in the Science and Technology Library, from the 16th century to the early 18th century, this quadrant was the most accurate navigation tool of this period.

Moreover, this kind of quadrant is easy to operate. You don’t have to pull a rope to look at the sun like using an astrolabe. Instead, you use the shadow projected by the stick onto the scale. The position of the shadow end indicates the altitude of the sun, so the latitude can be calculated. .

Xiao Ming put a lot of effort into making this quadrant. In fact, the structure of this quadrant is very simple. It is just two compasses, one big and one small, put together, but each of the two legs of the compass uses a curved wooden strip. connected, and there is a stick on each connected structure.

The most difficult part of the quadrant is the scale problem.

In order to make the scale accurate, the quadrant in Xiao Ming’s hand was a bit large, almost fifty centimeters long.

After all, the larger the scale interval, the easier it is to draw, and the error will be relatively smaller.

“Your Highness, do you use this to calculate the dimensions of the earth?” Yue Yun already understood what longitude and latitude are.

Xiao Ming nodded, “This is just an instrument. Now you have to learn how to calculate latitude and longitude, which is the formula for latitude and longitude.”

After saying that, Xiao Ming stood up and stood in front of the blackboard.

He wrote on the blackboard, “1 degree of latitude = about 111km, 1 minute of latitude = about 1.85km, 1 second of latitude = about 30.9m, 1 degree of longitude span = 111 kilometers, 1 degree of longitude across the latitude line = 111* cosA kilometers, where A is the latitude, the distance between any two points, d=111.12cos{1/[sinΦAsinΦB十cosΦAcosΦBcos(λB-λA)]}”

As soon as this formula came out, Yue Yun’s whole head felt big, and he was in pain. Covering his head, “Your Highness, can you not learn these things?”

“No, Xiao Ming answered very simply.”

Yue Yun’s and others’ mathematics skills can be said to be zero, and it is impossible to learn advanced mathematics all at once in the past few months. Mathematics, so Xiao Ming will not teach Yue Yun other mathematical knowledge.

He only asked Yue Yun to learn how to calculate dimensions in this way, which meant that he only needed to learn how to use this formula to calculate latitude and longitude.

In this way, his learning amount will be greatly reduced and he will only focus on this formula.

And Xiao Ming will also provide him with a calculation table of longitude and latitude. Even if he can’t calculate it by then, he can still determine his position by referring to the longitude and latitude calculation table, so that he will not wander off at sea.

In the past, Xiao Ming thought that navigation was a very simple matter, but after learning about navigation, he realized that it was a very complex system of knowledge. In the 18th century, walking along the coastline was not called navigation.

The current course is basically Yue Yun’s last course after going to the sea. From now on, he will go to the sea for trade, for the boundless wealth, and for Qingzhou’s most primitive capital accumulation.

(End of chapter)