Hongwu Survival Guide

Chapter 65 The First Lesson
Inside the Yinghai Envoy's mansion in Dinghai County, it was the morning of February 22.

There is a two-bay room in the right wing of Mingyuan Hall. Lao Zhu has not yet given a reply, and the mini Maritime Academy has opened ahead of schedule.

This is the first class.

Classrooms were arranged according to the classroom pattern in Zhu Yuan's memory. The main attendees were Liu Lian, Yao Feng and other officials from the Yinghai Division and Navy Commander's Mansion, and local officials could also attend the lectures if they wanted.

There are three rows and ten rows of double seats in the hall. Not only is it full, but those who come later can only find stools to sit in the middle aisle.

Zhu Yuan did this mainly to train teachers for the Maritime School to be opened in the future, and to set a model for new teaching.

Today's topic is tides.

inside the classroom.

When everyone was seated, Zhu Yuan signaled that Li Gui, the third younger brother of Qingniang who he had appointed as a teaching assistant, hung the physical 'PPT' made by the women in the inner house for him on a vertical board more than ten feet wide in front of the hall. This is a page Octavo large paper, on which is a simple topographic map of the coast of the Ming Dynasty, in which there are three lines on the sea surface, representing the three sea routes that the Yuan court traveled by sea in the past few decades. To sum up.

Holding a pointer made of twigs and knocking on the vertical board, Zhu Yuan said: "Tide, because it is related to livelihood, this is something that coastal people must know since they were young. Since everyone is a maritime officer, or works in Linhai Prefecture County, I think you must have a better understanding of tides than ordinary people."

"Look at this picture first. The line near the sea is the road map for the first time the Yuan court organized grain transportation by sea in the 19th year of the Yuan Dynasty, that is, 86 years ago. 60 shi. Compared with the other two far-sea routes, you may think that this short-sea route, which can see the land all the way, is safer, right?"

Zhu Yuan never deliberately changed his very vernacular or even weird way of speaking compared to this era, and everyone has gradually gotten used to it.

Others are actively or passively influenced to follow the imitation.

Listening to his questions, even if they have also done some research on shipping matters, some people still nod their heads unavoidably.

Again, fear comes from the unknown.

If you can see the land all the way in the process of transporting grain, your mentality will be a little more stable.

Zhu Yuan didn't wait for everyone to give feedback, and quickly continued: "The problem is that the offshore route is actually the most dangerous and the least efficient. There are many reasons. Let's not talk about others for now, just talk about the tide."

The pointer gestured between the mouth of the Yangtze River and the mouth of the Huanghuai River, and Zhu Yuan continued: "This section of the road is called 'Wanli Long Beach' by the coastal people. According to the latitude data returned by the Beishang surveying and mapping team, we are now You know, it’s actually only less than a thousand miles away. Then, why is it called a “beach”? Because it’s shallow! In this area, the high tide may barely be able to sail a boat. When the tide ebbs, the depth of the shallowest part is only a few feet, and there are dense reefs. Larger ships may run aground or run aground at any time. Once a large ship runs aground or capsizes, or hits a rock and enters the water, it will be even more difficult to rescue. Even if it is rescued, the cargo on board will often be damaged due to flooding.”

"This is the tide, which makes the sea route that should make us feel the most at ease, and becomes the most uneasy, so that Yuan Ting quickly gave up this seemingly stable offshore route."

While Zhu Yuan was talking, he gave a little gesture, and Li Gui quickly hung up the second 'PPT'.

Zhu Yuan walked over and said, "This is part of the recently completed map of Mingzhou's coastal waters. Mingzhou has been a good natural port since ancient times. Why? We still only talk about tides. Because many islands in the outer sea are constantly slowing down and hindering the flow of large and small tides to the coast. The impact allows ships to berth with confidence. Compared with other harbors facing the sea that lack shelter, if there is a high tide, the berthed ships may even be overturned."

Having said that, Li Gui has already hung up the third picture, and put a strange model with three balls, big and small, on the desk in front of the hall.

Zhu Yuan also continued: "I just said this to let everyone have a general understanding of the tide. This is the force of heaven and earth. We can't reverse it, we can only follow the trend."

"Next, let's talk about the reasons for the formation of tides." Zhu Yuan came to the desk and fiddled with three large and small balls to make them rotate: "This is a model of the sun, the earth and the moon orbiting each other. Don't doubt it. I doubt it for a while. I don’t have time to explain to you. Let’s talk about why they surround each other first, which involves the two concepts of gravitation and centrifugal force.”

Zhu Yuan picked up the pointer again as he spoke, and pointed to the two related terms on the 'PPT' page on the vertical board.

under the hall.

According to Zhu Yuan's request, everyone was taking notes with pen or charcoal.

However, if Zhu Yuan just took the offshore route and Mingzhou seaport as an example, it is relatively easy for everyone to understand. When it comes to the sun, the earth, and the moon surrounding each other, and when it comes to gravitation and centrifugal force, everyone feels, as if in an instant, everyone's thinking From a relatively familiar world, I jumped directly to another strange world that I had never considered.

Unknowingly opened their eyes wide, Liu Lian and Zhu Yuan, who forgot to record for a while, roughly explained the relevant concepts, and even found a pebble and dropped it on the spot, demonstrating to everyone the "universal gravitation" that they would never think about on weekdays , finally couldn't help it, interrupted: "Hanlin..."

Zhu Yuan looked over: "Huh?"

Liu Lian felt that his mouth was a little dry. As a tireless and pious scholar, the microscope a few days ago had already had an impact on his world view. This time, there was another impact. He paused and asked: "What is this?" ...Gravity, is... um, how did it come about?"

When Liu Lian asked this question, everyone in the hall turned to look at Zhu Yuan, and Xue Shu, the magistrate of Dinghai County, who was in the back row today who squeezed in time to attend the lecture, even stood up.

Zhu Yuan thought for a while, raised his hand and scratched in the air: "Do you think our surroundings are empty? No. Our surroundings are all air. However, if the air is removed, is it empty? Still not. Then What is it? The answer I can give you is 'space'."

Speaking of this, Zhu Yuan paused for a while, and then said: "Everyone knows the principle that water flows to low places. If you dig a hole and pour water around it, the water will definitely flow into the hole. Similarly, the sun, the earth and the moon are relatively As far as we human beings are concerned, it is very huge, so huge that the 'space' is pressed out of various large and small 'pits'. The sun's 'pit' is the largest, so the earth slides towards the sun, and maintains its balance by virtue of the centrifugal force around it. By analogy, the same is true between the earth and the moon. As for us small human beings, on the earth, we are also like the water flow in the potholes, and in the space around the earth that is pressed out of the 'pit', we will Involuntarily sliding down to the bottom of the 'pit', that is, the ground we are on. When this state is embodied in reality, it manifests as a kind of gravitation, that is, universal gravitation."

As Zhu Yuan said, he picked up the pebble that had just been thrown on the ground again, let it go again, and with a thumping sound, he said, "Look, this stone has flowed to the bottom of the 'pit' again."

After hearing Zhu Yuan's words, Liu Lian felt his head buzzing.

Feel it.

I... really fell into the pit.

This pit is so deep!

Later... Liu Lian felt that he should write a letter to his father immediately to share... Oh, no, share it!
Zhu Yuan looked down the hall.

Even if he is not a pious scholar like Liu Lian, he is more or less lost in his mind. After all, what he said has completely surpassed the cognition of ordinary people in this era, especially some scholars, whose understanding of the world has been formed for decades. The inherent concept was completely subverted in a blink of an eye.

Zhu Yuan couldn't help but twitched the corners of his mouth slightly.

on purpose.

Shocking the world view of these people and feeling how small they are can easily make people get rid of low-level interests.

Without so many low-level fun, it is easier to use.

After waiting for a while, Zhu Yuan knocked on the vertical board to attract everyone's attention, walked to the "PPT" page that Li Gui hung up again, and continued: "If you still have doubts, we will talk about it later. Let's continue to talk about tides. The reasons for the formation of tides , because the gravitational force of the sun and the moon pulls the seawater on the surface. When the sun and the moon form a line, that is, around the first and fifteenth day of each month, the gravitational force is the largest, forming two spring tides per month. As shown in the figure. When the moon is in On the Earth side, at right angles to the Sun, the gravitational forces cancel each other out, resulting in two low tides per month."

"As for the daily tides, the same is true." Zhu Yuan turned to another page of diagrams hung up by Li Gui: "Under the background of the earth's rotation, the moon's gravitational pull causes the tides to ebb and flow twice a day."

Speaking of this, Zhu Yuan glanced down the hall and saw that Liu Lian was still in a daze, raised the pointer and knocked on the desk in front of the hall, signaling Liu Lian: "Wake up, don't forget to record, yours is for filing."

Liu Lian recovered and nodded quickly.

Feeling that it was not enough, he simply stood up and bowed to Zhu Yuan.

This bow is for those scholars.

Liu Lian's family has a long history of education, and he has never suffered from studying, but he also understands that learning is hard to come by, because he has seen some poor students serve their teachers more dedicatedly than their parents in order to study, just to have more opportunities to ask for advice.

Someone in front of me...

From "Fundamentals of Mathematics" and "Sketching Techniques" a few days ago, to the current "Gravity" and "Tide Science", they were just thrown out casually, so casually that it was not even respectful.

Liu Lian felt that this was not right.

How can we treat learning like this?

However, after thinking about it carefully, Liu Lian felt that this might be the kindness that a university student should have, instead of letting his disciple serve like a slave for many years before he is willing to give something.

In the classroom, Zhu Yuan continued to talk, not knowing what Liu Lian was thinking.

Even if he knew it, he would just smile.

Cherish your broom?

In fact, Zhu Yuan has no shortage of similar thoughts.

The problem is that, just like the "Basics of Mathematics", in fact all of these are just 'basics'.If even a series of basic knowledge has to be hidden, Zhu Yuan feels that this country should not talk about entering the industrial age ahead of schedule.

After all, the popularization of education is also a basic condition for industrialization.

The same is true for the recently planned Maritime Academy.

If there is a lack of sufficient maritime-related talents, exploring the ocean will only be empty talk.

(End of this chapter)