Lu Xun returned from his voyage around the world and recounted what he had seen and heard during the voyage. One of the ministers said, "Bo Yan said that the earth is round, and we are on top of the earth, so don't the people on the other side of the earth have their heads down?" ”

Hearing him say this, Liu Xie couldn't help but smile secretly in his heart, but the ministers above the court all waited for Lu Xun to answer this question with a serious face.

This is the Eastern Han Dynasty, although under the drive of Liu Xie, there have been many things beyond this era, but most of the people's worldview is still maintained at the level of the round sky.

So there are a lot of people who don't know that the earth is round.

Except for Liu Xie, only Huang Yueying knows that the earth is round, after all, she is also from the future.

Lu Xun said: "I don't know about this, but I can tell you all very responsibly, the earth is indeed round, otherwise I have been sailing east, why can I finally come back from the west?" ”

The minister said, "It may be in the easternmost place of the sunrise, and there is a passage, and after passing through, you will immediately reach the place of sunset in the west." Otherwise, you won't be able to explain that the earth is round, and the people on the other side don't fall. You say, don't you? ”

Everyone agreed.

Liu Xie held back for a long time, and said with a smile: "Okay, you don't have to guess, I will solve your doubts." Little Luozi, go to the slide show! Close the door and avoid the light! ”

Cameras can do it, and slide projectors are no problem. The doors and windows of the Qinzheng Hall were all closed, the hall was immediately darkened, the curtain was lowered, and the slide projector was set up.

"The Sun, a great burning ball of fire, which provides us with heat, warmth and light, surrounds it with several planets, the first one: the Celestial Star, which also has the name of the Evening Star, and because it is closest to the Sun, it can only be observed in the early hours of the morning and at dusk, so it is called the Celestial Star or Evening Star, which we call Mercury.

"The second closest star to the Sun is the Tai Bai Star that everyone is familiar with, and it is also called the Morning Star and the Chang Gung Star.

"The third star, this blue star, is called Earth, but for many years we have called it ......"

When the palace maid who was the docent said this, she suddenly stopped, looked at everyone, and saw that everyone had an expectant expression, and then said, "Earth." ”

As soon as she finished speaking, there was an immediate commotion, and the minister just now said, "You mean to say that the earth is a huge ball, and we all live on it?" ”

The palace maid said, "Yes, my lord, what you said is completely correct, we are on top of this huge ball, and this ball is called the earth. ”

The minister spread his hands and said, "This, this is ridiculous, isn't it?" We live on this ball, so how can it not fall? And the sea, isn't it all the water in the sea? ”

The minister's words were immediately echoed by everyone, and they all started talking.

The palace maid really couldn't explain anymore, so she looked back at Liu Xie helplessly, Liu Xie shrugged her shoulders and motioned her to wait for everyone to stop talking before continuing to explain.

Finally calmed down a little, and the minister just now asked, "You say, how do you explain this?" ”

The palace maid said: "There is a thing called gravitation, everything in the universe is attractive, the larger its volume, the greater the gravitational force, and vice versa, the smaller it is, so small that it cannot be felt, it can be ignored." And the earth has a huge gravitational pull, and everything on the earth, including us humans, is attracted by this gravitational attraction and will not fall down like this adult said, and in the same way, the sea water will not flow down if it is also attracted by gravity. ”

"Gravity?" The ministers were stunned again. Just now, the minister insisted again: "Okay, even if you are right, the earth, oh no, you are talking about the earth, the earth has gravity, and it sucks us all and does not fall, but the person who lives under the earth, doesn't he feel dizzy with his head down?" Lu Xun, you said, you sailed around the world, you must have gone to the other side of the earth, do you have the feeling of being head-down? ”

He spread his hands one after another and said, "Not really, I've always been head-up." ”

The palace maid explained here: "My lord, since the earth has gravity, then we on the earth, no matter where we are on the earth, we will feel head up, and there is no feeling of head down at all. And there is no such thing as going up and down in the universe. ”

"No up and down? How is this possible? "Then according to your meaning, can we understand that your head is an ass, and your ass is a head?" ”

Everyone laughed, and the palace maid was in tears.

Huang Yueying stood up and said, "Okay, then I'll talk to you." ”

Huang Yueying really couldn't stand it anymore, so she stood up and said: "There is indeed no difference between up and down in the universe, but on the earth, there is, a person standing on the earth, the direction towards the center of the earth is down, and the direction towards the sky is up." So on the earth facing the earth in any direction is up. Do you understand? Okay, this sister, you go on. ”

Regarding Huang Yueying's explanation, everyone did not question it anymore, and the palace maid began to continue to talk about it, saying all the eight planets of the solar system.

The reason why Liu Xie wants everyone to understand these is to let the ministers have a scientific world view, which will also have a great role in promoting the development of the Han Dynasty in the future.

After giving a general explanation of the knowledge of the solar system, the palace maid began to introduce the seven continents and four oceans on the earth. In order to unify the understanding, Liu Xie directly adopted the name of the future after 1800 to call the place names in the world, and did not name them separately, which saved trouble.

While introducing the knowledge of the earth, the ministers did not make any more commotion, and they all listened carefully. A morning passed so quickly.

After explaining, Liu Xie asked people to open the doors and windows, remove the slide projector, and hang up the world map. Then he said to everyone: "I have been thinking about the future development plan these days, what is the development direction of our Han?" ”

A minister raised his hand, and Liu Xie pointed at him and said, "You come on." ”

I only heard this minister say: "Weichen thinks that the development direction of our Han is to look at the world, I mean the whole world, no, the whole earth!" ”

Liu Xie pointed at him and said, "What you said is so good, you said my plan." Starting from today, every day in the future, there will be an hour of modern lectures like today's in the court. ”

(End of chapter)