I was engaged in infrastructure construction in the Han Dynasty [Transmigration Book]

Liu Tan took a deep breath and said, "This has nothing to do with fairy art. If this is also immortal art, then the things that the emperor uses on a daily basis also have fairy art."

Liu Che was a little surprised: "Oh? Tell me."

Liu Tan pointed to the palace lantern next to him and said, "This is the same as the toilet."

Thanks to the wise ancient people for making his science popularization not so difficult.

In the Han Dynasty, the principle of siphon was actually used consciously, but everyone knew that it was possible to do so, but they did not summarize the rules that could be spread.

And because of the lack of a scientific and technological system, most people will not learn these in the process of being educated, so this principle has actually been applied in daily life, but it cannot be connected in another form.

Liu Tan asked Miao Rui to go to the semi-finished toilet in the palace to get a cross-section, and walked to the side of the palace lantern and said, "I call this phenomenon the siphon principle, and the palace lantern also uses this principle. The copper tubes on both sides are siphons. It is also a smoke guide pipe, and there is water stored below. When the lamp smoke is generated, because its position is high enough, and the bottom of the smoke guide pipe is relatively low, a siphon effect will be formed, and the smoke will enter the bottom of the smoke guide pipe to be eliminated by water. cigarette."

When Liu Tan was thinking about whether he wanted to popularize the principle of gravity, Liu Che asked, "So it's the same?"

At this time, the toilet that Liu Tan was asked to use as a demonstration was also sent over. This time, because the cross-section looks more intuitive, Liu Tan pointed to the pipeline of the toilet and asked, "Do you think this is the same?"

Liu Che looked at it and said, "What's the same?"

Liu Tan patiently explained: "It's like the water reservoir of the palace lantern is connected to the lower part, and the smoke guide pipe is here, because the toilet needs greater suction, so this pipe is designed like this."

Liu Che had some regrets: "So it's not fairy art."

Liu was so tired of talking that he almost lay down on the toilet: "If it's really a fairy art, how can it be so easy to appear in the world?"

There is no need to say that there is no fairy art or immortal in this world, because even if Liu Che is told, he may not believe it, or if he says it, everyone will only think that he is cheating.

If Liu Che can realize that immortals and immortal arts are unattainable existences, even the emperor should not even think about it, maybe it will be much better.

Liu Tan said so, but Liu Che believed it. He said with some melancholy: "It is true, otherwise why have you only heard of immortals but not immortals for so many years?"

Liu Tan said in a low voice: "The immortals they saw may not be real, maybe they misunderstood? They haven't even seen the emperor, so what qualifications do they have to see them? Comparable to Father Emperor?"

As expected, Liu Che's attention was attracted and he asked, "You mean, if I can't see it, the rest of the world won't be able to see it?"

Liu Tan nodded seriously: "Yes, sometimes the fairyland or immortals they see may not be real, even if they see them, they may be left over from the past."

Compared with science, Liu Che was obviously more interested in theology, so he asked, "What does it mean to be left over from the past?"

Liu Tan casually said: "The so-called legacy of the past means that the immortal once appeared here, but when someone sees it, he or that place is no longer there. It is said that one day in the sky and one year in the world..."

"Wait, one day in the sky and one year in the world?" Liu Che widened his eyes: "Where did this saying come from?"

Liu Tan: ...

Gan, I slipped my tongue.

Hey, the mythology system of the florist is too complicated, and the evolution is also very complicated. Sometimes it is impossible to know when certain things that everyone is familiar with evolved.

Liu Tan once also read papers on the ancient mythology system, but he almost forgot about it after so long.

Now he thought everyone knew about it, but in Liu Che's opinion, it was the first time he had heard of it.

Liu Tan paused for a short while, and began to think about how to get it right, but before he could think it through, Liu Che had automatically skipped this topic: "Well, there's no need to say more about this, you can continue."

Liu Che has automatically thought: If the son does not speak, it means that he cannot speak.

Anyway, he just remembered this sentence, and there was no need for Liu Tan to explain it.

But when he said that, Liu Tan felt uneasy, and couldn't help but said, "This... there are sporadic records..."

Liu Che nodded perfunctorily: "Yes, I understand."

Liu Tan struggled unsuccessfully, so he just whispered, "I forgot what to say."

Liu Che:? ? ? ?

Bu Fan on the side reminded in time: "Your Highness said that one day in the sky has been in the world for one year."

Liu Tan tilted his head and thought for a while: "Oh, yes, because time is not equal, and immortals rarely stay in the same place for too long except for their own caves, so when someone sees it, it is just time. keep..."

Liu Tan was a little stuck when he came to this point. He suddenly realized that he was talking too much nonsense. The concept of time preservation... how should he explain it?

Fortunately, Liu Che never gets to the bottom of it, he pays more attention to the answer.

After hearing what Liu Tan said, he frowned and said, "So, no wonder I never saw it when I went to Penglai to seek immortality, presumably the immortal is no longer there."

Liu Che asked again: "Where do the immortals usually go? Do they prefer mountains or the sea? If we build a high platform, will we be able to see them?"

Liu Tan glanced at Liu Che, and the villain in his heart rolled up his sleeves, he had already fooled him anyway, so let's fool him to the end.

"It's not fixed where the immortals go, and what everyone likes is not fixed. The high platform... no matter how high it is, it can't be higher than the stars in the sky, so you can't see it."

"Stars?" Liu Che was a little confused: "Aren't those stars the immortals themselves?"

Liu Tan said: "It's okay to say that, anyway, they live on it."

Liu Che was quite moved: "What is it like on the stars?"

Liu Tan said: "They are all different. Some are frozen for thousands of miles, some are covered with terracotta, and some have flames all over them."

Liu Che was a little surprised: "This... how can I live?"

Shouldn't the place where immortals live be Changchun where birds are singing and flowers are fragrant all the year round?

Liu Tan said: "Immortal caves are not just for living. Immortals also have to practice. They can also see a wider world, so they will find a place to sharpen themselves. However, immortals generally do not have only one cave. It’s not good, but it’s beautiful to play with.”

"What do those caves look like?"

Liu Tan racked his brains: "The roads are wide and clean, and the buildings reach into the sky. At night, there will be lights of various shapes and colors on those buildings and on both sides of the road. Some places with many people will be very lively..."

As he talked, Liu Tan was a little lost in thought. After traveling for so long, he thought he had adapted to the life here.

However, when he talked about it, he realized that he missed it a little.

He stopped talking about Liu Che and didn't urge him. The nostalgia on Liu Tan's face was obvious. Liu Che suddenly regretted asking too much. What if Liu Tan couldn't make up for the longing and left?

Liu Tan was distracted for a short period of time, and soon he came back to his senses and said embarrassedly: "I don't know anything else."

Although Liu Che felt that he shouldn't ask, he still couldn't help asking: "Then how can I go to the fairy world?"

Liu Tan looked at Liu Che seriously and asked, "Is Father really going?"

Liu Che hesitated a little, but still said, "I yearn for it in my heart."

Liu Tan simply said: "It's not that you can't come back after going to the fairyland, but you can't go now. If you want to go, you have to meet a condition."

Liu Che was really concerned and asked, "What is it?"

Liu Tan said one word at a time: "Develop the technique of investigating objects, and when the technique of investigating objects reaches a certain level, you will naturally be able to go to the fairy world."

Come on, our journey is the sea of ​​stars.